Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 31 December 2023
CONGRATULATIONS TO KEVIN TRENBERTH granted a New Year award to be a
Companion of the NZ order of merit for services to Geophysics (Climatology).
Tonight, the calendar ticks over to 2024.
We seem to start our calendar year at a strange part of our orbit around the
sun. I like to think of each solar orbit having four corners, and it would
be logical to choose one of these corners to start the year.
Logically the four corners are the two equinoxes and the two solstices.
Indeed, before Roman times March 21st (Spring equinox) was taken to be the
start of the year. But around 700 BCE King Numa Pompilius (the second of 7
Kings before Rome become a Republic) switched that to the start of January
(their god of new beginnings) rather than March.. ruled by Mars, their god
of war). Anything for a quieter life.
This has continued to mark the start of the solar year. Even so, there are
several festivals around the world that are triggered by solstice and
equinox. The most notable is in the timing of Easter--- which is triggered
by the date of the passive rand is the first Sunday after the Paschal moon
which is the first full moon after the March Equinox.
Here is a list of festivals based on the "four corners" of the year:
When Who/Where What Why
From 5 Jan to end of Feb China Harbin Ice Mid winter
8 to 14 Jan India Kite Festival Peak wind
28 Jan Japan Wakakusa Yamayaki Grass fires to drive away boars
31 Jan Scotland Up Helly Aa end of winter yule
4-11 Jan Japan Sapporo Snow ice sculptures
2 Feb USA Groundhog Day pre-spring.
5 Feb USA Weatherperson's Day/John Jeffries Birthday
5-19 Feb Taiwan Lantern Festival end of Lunar new year
16-22 Feb Bolivia Oruro Carnival precursor to Lent.
21 Feb New Orleans Mardi Gras Shrove Tuesday.
17-25 Feb Brazil Carnival Pre lent.
8 March India Holi start of spring.
23 March UN World Meteorological Day
2-6 April Bhutan Paro Tshechu Spring
2-8 April Guatemala Semana Santa Spring/Holy week
Early May Boun Bang Fai Rocket Day Thailand/Laos Spring
22 June Peru IntiRaymi Solstice
28 June (2024) NZ Matariki Mid (southern) winter
Early July US The Dog Days (Sirius) Mid (northern) summer
15 July UK St Swithin's Day predicts next 40 days of rain
Mid Sep to early Oct full moon China Mook cake day/Harvest moon full moon
after equinox
Late December old Norse word YULE Tide /Christmas Solstice
YULE tide is a phrase referring to the "12 nights of Christmas" but
originally was, probably, taken from a Norse name for feasting to mark
mid-winter solstice.
TROPICS
All looks quiet for the start of 2024
The MJO, a burst of extra energy in the tropics, is now weakening and
leaving the Pacific, so the next few weeks should be quieter than normal.
WEATHER ZONES
The South Pacific Convergence zone is expected to have a quiet week and
mainly be between Solomon Islands and Suwarrow.
HIGHS and LOWS
Low L1 crossing NZ on New Years eve is expected to move off to the east
followed by HIGH H1 crossing NZ mid-week.
Low L2 is expected to form east of Tasmania on Wednesday and reach central
NZ around Friday 5 January.
Showery at times this between in North Tasman between Brisbane and Noumea.
Avoid.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
31 December 2023
24 December 2023
Bob Blog
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 24December 2023
As a fitting topic for this Christmas edition of my blog, THREE KINGS
ISLANDS
The Muriwhenua Maori of the far north tell how navigator Kupe discovered and
explored the region.
They inhabited these offshore islands and named the largest MANAWATAWHI ---
(panting breath).
New Year 1643
On 6 January Abel Tasman came across the Islands and since this was the
Epiphany (12th night of Christmas) he named them Drie Koningen Eyland (The
Three King Islands). He noticed the largest was inhabited and didn't hang
around.
December 1769
Rounding The Top Of New Zealand
It took Endeavour from 11 to 30 December to round the top end due to light
winds and then a passing front.
On Christmas day they identified Three Kings, as reported in the log, as
seen at
www.captaincooksociety.com/cooks-voyages/first-pacific-voyage/october-decemb
er-1769
>>>>>>>>>>>>>>>>>>>>>>>>>>>>
As Endeavour neared North Cape, the weather could be calm. On 11 December,
Cook recorded "Gentle breezes at NW and pleasent weather. Kept plying all
this day, but got very little to windward". Banks praised the ship, "we
turnd [tacked] all day without loosing any thing, much to the credit of our
old Collier, who we never fail to praise if she turns as well as this". Two
days later, "heavy squalls attended with rain... split the Main topsail in
such a manner that it was necessary to unbend it and bring another to the
yard... At Noon had strong gales and hazy weather—tack'd and stood to the
westwd. No land in sight, for the first time since we have been upon the
Coast" of New Zealand. In the evening, Cook "brought the ship under her
Courses having first split the fore and Mizn Topsails". The next day he "Set
the Topsails close reef'd and the people to work to dry and repair the
damaged sails".
On 14 December, Cook "Saw land bearing SW being the same North-Westermost
land we have seen before and which I take to be the northern extremity of
this Country as we have now a large swell rowling in from the westward which
could not well be was we covered by any land on that point of the compass".
Banks agreed, "a heavy swell from the west made us almost conclude that
there was no land to the Northward of us".
The next day, Cook "stood to the westward with as much sail as the Ship
could bear". The next day, he "got topgt yards up and set the sails, unbent
the foresail to repair and brought another to the yard". And, on the next
day "the people at work repairing the Sails, the most of them having been
split in the late blowing weather". John Ravenhill was the sailmaker in
charge.
On 18 December, Cook named the land they could see "North Cape judging it to
be the northern extremity of this Country". Banks spotted something. "On a
rock pretty near us an Indian fort was seen through our glasses which we all
thought was encircled with a mud wall; if so tis the only one of the kind we
have seen".
Two days later, Banks had "hopes of a fair wind in the morn but they soon
left us and it began to blow hard with violent claps of thunder, on which we
again stood out to sea". The following day there was "a great swell from the
West". On the next day "the wind has come more to the Southward so that we
cannot come in with the land at all".
Christmas Time
On Christmas Eve Cook saw land "bearing SSE distant 8 Leagues... It proves
to be a small Island which we take to be the Three Kings discover'd by
Tasman: there are several smaller Islands or Rocks lying off the SW end and
one at the NE end". It was, wrote Banks, "Calm most of the Day: myself in a
boat shooting in which I had good success, killing cheifly several Gannets
or Solan Geese so like Europaean ones that they are hardly distinguishable
from them. As it was the humour of the ship to keep Christmas in the old
fashiond way it was resolvd of them to make a Goose pye for tomorrows
dinner".
On Christmas Day "Our Goose pye was eat with great approbation and in the
Evening all hands were as Drunk as our forefathers usd to be upon the like
occasion". Not surprisingly, the following day "all heads achd with
yesterday's debauch". Cook did not record the meal in his journal.
On 30 December, Cook "wore and stood to the SE and being pretty moderate we
set the Topsails close reef'd, but the SW Sea runs so high that the Ship
goes boddily to leeward. At 6 Saw the land bearing NE distant about 6
Leagues which we judge to be the same as Tasman calls Cape Maria van
Diemen".
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
As for the inhabitants, local Māori farmers stayed on the Island until the
late 1830s, then gave up on it and returned to the mainland.
TROPICS
JELIWAT brought some rain to southern parts of the Philippines.
The MJO a burst of extra energy in the tropics, is now weakening and leaving
the Pacific, so the next few weeks should be quieter than normal.
WEATHER ZONES
The South Pacific Convergence zone is strong near 3 to 5S as far as
Tuvalu/Tokelau and then in a line from Niue to Tahiti.
HIGHS and LOWS
HIGH H1 to east of NZ should continue moving off to east.
Low L1 is crossing NZ for Christmas then moving off to the east, followed by
clearing weather as H2 visits NZ mid-week.
Low L2 is expected to deepen off Sydney mid-week and cross NZ this weekend
as a trough.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 24December 2023
As a fitting topic for this Christmas edition of my blog, THREE KINGS
ISLANDS
The Muriwhenua Maori of the far north tell how navigator Kupe discovered and
explored the region.
They inhabited these offshore islands and named the largest MANAWATAWHI ---
(panting breath).
New Year 1643
On 6 January Abel Tasman came across the Islands and since this was the
Epiphany (12th night of Christmas) he named them Drie Koningen Eyland (The
Three King Islands). He noticed the largest was inhabited and didn't hang
around.
December 1769
Rounding The Top Of New Zealand
It took Endeavour from 11 to 30 December to round the top end due to light
winds and then a passing front.
On Christmas day they identified Three Kings, as reported in the log, as
seen at
www.captaincooksociety.com/cooks-voyages/first-pacific-voyage/october-decemb
er-1769
>>>>>>>>>>>>>>>>>>>>>>>>>>>>
As Endeavour neared North Cape, the weather could be calm. On 11 December,
Cook recorded "Gentle breezes at NW and pleasent weather. Kept plying all
this day, but got very little to windward". Banks praised the ship, "we
turnd [tacked] all day without loosing any thing, much to the credit of our
old Collier, who we never fail to praise if she turns as well as this". Two
days later, "heavy squalls attended with rain... split the Main topsail in
such a manner that it was necessary to unbend it and bring another to the
yard... At Noon had strong gales and hazy weather—tack'd and stood to the
westwd. No land in sight, for the first time since we have been upon the
Coast" of New Zealand. In the evening, Cook "brought the ship under her
Courses having first split the fore and Mizn Topsails". The next day he "Set
the Topsails close reef'd and the people to work to dry and repair the
damaged sails".
On 14 December, Cook "Saw land bearing SW being the same North-Westermost
land we have seen before and which I take to be the northern extremity of
this Country as we have now a large swell rowling in from the westward which
could not well be was we covered by any land on that point of the compass".
Banks agreed, "a heavy swell from the west made us almost conclude that
there was no land to the Northward of us".
The next day, Cook "stood to the westward with as much sail as the Ship
could bear". The next day, he "got topgt yards up and set the sails, unbent
the foresail to repair and brought another to the yard". And, on the next
day "the people at work repairing the Sails, the most of them having been
split in the late blowing weather". John Ravenhill was the sailmaker in
charge.
On 18 December, Cook named the land they could see "North Cape judging it to
be the northern extremity of this Country". Banks spotted something. "On a
rock pretty near us an Indian fort was seen through our glasses which we all
thought was encircled with a mud wall; if so tis the only one of the kind we
have seen".
Two days later, Banks had "hopes of a fair wind in the morn but they soon
left us and it began to blow hard with violent claps of thunder, on which we
again stood out to sea". The following day there was "a great swell from the
West". On the next day "the wind has come more to the Southward so that we
cannot come in with the land at all".
Christmas Time
On Christmas Eve Cook saw land "bearing SSE distant 8 Leagues... It proves
to be a small Island which we take to be the Three Kings discover'd by
Tasman: there are several smaller Islands or Rocks lying off the SW end and
one at the NE end". It was, wrote Banks, "Calm most of the Day: myself in a
boat shooting in which I had good success, killing cheifly several Gannets
or Solan Geese so like Europaean ones that they are hardly distinguishable
from them. As it was the humour of the ship to keep Christmas in the old
fashiond way it was resolvd of them to make a Goose pye for tomorrows
dinner".
On Christmas Day "Our Goose pye was eat with great approbation and in the
Evening all hands were as Drunk as our forefathers usd to be upon the like
occasion". Not surprisingly, the following day "all heads achd with
yesterday's debauch". Cook did not record the meal in his journal.
On 30 December, Cook "wore and stood to the SE and being pretty moderate we
set the Topsails close reef'd, but the SW Sea runs so high that the Ship
goes boddily to leeward. At 6 Saw the land bearing NE distant about 6
Leagues which we judge to be the same as Tasman calls Cape Maria van
Diemen".
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
As for the inhabitants, local Māori farmers stayed on the Island until the
late 1830s, then gave up on it and returned to the mainland.
TROPICS
JELIWAT brought some rain to southern parts of the Philippines.
The MJO a burst of extra energy in the tropics, is now weakening and leaving
the Pacific, so the next few weeks should be quieter than normal.
WEATHER ZONES
The South Pacific Convergence zone is strong near 3 to 5S as far as
Tuvalu/Tokelau and then in a line from Niue to Tahiti.
HIGHS and LOWS
HIGH H1 to east of NZ should continue moving off to east.
Low L1 is crossing NZ for Christmas then moving off to the east, followed by
clearing weather as H2 visits NZ mid-week.
Low L2 is expected to deepen off Sydney mid-week and cross NZ this weekend
as a trough.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
17 December 2023
Bob Blog 17 dec
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 17 December 2023
EL NINO dynamic
This El Nino episode may now be at its peak.
The atmospheric SOI values are relaxing..
The Ocean:
The parameter used from the ocean is based on the sea surface temperatures
in the equatorial eastern Pacific and called the NINO 3.4 SST anomaly.
Recent forecasts show that the Sea surface temperature anomalies in the Nino
3.4 area may have peaked and in JFM will start relaxing.
This El Nino has been twined with a positive IOD (Indian Ocean Dipole) with
the combo shifting activity into the mid pacific.
However the IOD has gone thru a relaxation process recently
And so this En Nino may soon start shifting focus more to the east.
TROPICS
JASPER made landfall near Port Douglas, QLD bring damaging wind and rain.
JELIWAT has just formed eats of the Philippines
The MJO, a burst of extra energy in the tropics, is expected to peak over
the Pacific Ocean in the next two weeks.
WEATHER ZONES
The South Pacific Convergence zone is strong near Vanuatu to across
Fiji/Tonga /Samoa to Tahiti region. .
HIGHS and LOWS
Low L1 is expected to form off SE of Sydney by mid-week and travel off to
the SE.
High H1 to NE of North Island is quasi stationary or expected to slowly
creep westwards.
Hight H2 may travel across South Island and bloom east of South Island
briefly then fade.
Trough between H1 and H2 expected to cross North Island on Monday then fade
away.
High H3 to west of Tasmania by mid-week is expected to cross the South
Tasman Sea on Friday and reach east of South Island by Saturday.
Low L2 should form over inland QLD by mid -week and travel SE to be off
Sydney by weekend.
Low L3 is expected to spread SW onto New Caledonia by mid-week then continue
SW and fade in Tasman Sea.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 17 December 2023
EL NINO dynamic
This El Nino episode may now be at its peak.
The atmospheric SOI values are relaxing..
The Ocean:
The parameter used from the ocean is based on the sea surface temperatures
in the equatorial eastern Pacific and called the NINO 3.4 SST anomaly.
Recent forecasts show that the Sea surface temperature anomalies in the Nino
3.4 area may have peaked and in JFM will start relaxing.
This El Nino has been twined with a positive IOD (Indian Ocean Dipole) with
the combo shifting activity into the mid pacific.
However the IOD has gone thru a relaxation process recently
And so this En Nino may soon start shifting focus more to the east.
TROPICS
JASPER made landfall near Port Douglas, QLD bring damaging wind and rain.
JELIWAT has just formed eats of the Philippines
The MJO, a burst of extra energy in the tropics, is expected to peak over
the Pacific Ocean in the next two weeks.
WEATHER ZONES
The South Pacific Convergence zone is strong near Vanuatu to across
Fiji/Tonga /Samoa to Tahiti region. .
HIGHS and LOWS
Low L1 is expected to form off SE of Sydney by mid-week and travel off to
the SE.
High H1 to NE of North Island is quasi stationary or expected to slowly
creep westwards.
Hight H2 may travel across South Island and bloom east of South Island
briefly then fade.
Trough between H1 and H2 expected to cross North Island on Monday then fade
away.
High H3 to west of Tasmania by mid-week is expected to cross the South
Tasman Sea on Friday and reach east of South Island by Saturday.
Low L2 should form over inland QLD by mid -week and travel SE to be off
Sydney by weekend.
Low L3 is expected to spread SW onto New Caledonia by mid-week then continue
SW and fade in Tasman Sea.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
10 December 2023
Bobgram 10 Dec
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 10 December 2023
2023 Ozone layer
During November, instead of doing it normal seasonal decay, the Ozone hole
area remained much the same, so that in early December it has been breaking
the December record.
The Antarctic ozone hole has been slow to fill in over recent years as
measured by atmosphere.copernicus.eu.
Some expect this may be related to global warming, which tends to cool
stratospheric temperatures and changes stratospheric chemistry and dynamics.
Ozone depletion is also believed to be influenced by greenhouse gas
emissions, volcanic and wildfires aerosols or even changes in the solar
cycle.
Another possibility for this year's weird behaviour is due to a residual of
water vapour in the stratosphere left over from last year's Hunga Tonga
-Hunga Ha'apai volcanic eruption.
Whatever the cause, these measurements are concerning.
TROPICS
JASPER formed over the Solomon Islands and is moving slowly westwards across
the Coral Sea and intensifying. It is expected to make landfall near
(probably north of) Cairns on Wednesday. Avoid.
The MJO, a burst of extra energy in the tropics, is expected to peak over
the Pacific Ocean in the next two weeks.
WEATHER ZONES
The South Pacific Convergence zone is strong from Solomon Islands to Samoa
to Tahiti.
JASPER is travelling westwards across the Coral Sea. A Low /trough L1 over
Tonga is expected to travel off to the south by mid-week a d another L2 near
Niue is expected to deepen the weekend and go south early next week. Avoid.
HIGHS and LOWS
Lows are expected to travel quickly across southern and eastern NZ: one on
Monday and another on Thursday, followed by large southerly swells in the
eastern Tasman Sea.
HIGH H1 in Tasman Sea by mid-weak is expected to cross northern NZ on
Thursday and Friday.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 10 December 2023
2023 Ozone layer
During November, instead of doing it normal seasonal decay, the Ozone hole
area remained much the same, so that in early December it has been breaking
the December record.
The Antarctic ozone hole has been slow to fill in over recent years as
measured by atmosphere.copernicus.eu.
Some expect this may be related to global warming, which tends to cool
stratospheric temperatures and changes stratospheric chemistry and dynamics.
Ozone depletion is also believed to be influenced by greenhouse gas
emissions, volcanic and wildfires aerosols or even changes in the solar
cycle.
Another possibility for this year's weird behaviour is due to a residual of
water vapour in the stratosphere left over from last year's Hunga Tonga
-Hunga Ha'apai volcanic eruption.
Whatever the cause, these measurements are concerning.
TROPICS
JASPER formed over the Solomon Islands and is moving slowly westwards across
the Coral Sea and intensifying. It is expected to make landfall near
(probably north of) Cairns on Wednesday. Avoid.
The MJO, a burst of extra energy in the tropics, is expected to peak over
the Pacific Ocean in the next two weeks.
WEATHER ZONES
The South Pacific Convergence zone is strong from Solomon Islands to Samoa
to Tahiti.
JASPER is travelling westwards across the Coral Sea. A Low /trough L1 over
Tonga is expected to travel off to the south by mid-week a d another L2 near
Niue is expected to deepen the weekend and go south early next week. Avoid.
HIGHS and LOWS
Lows are expected to travel quickly across southern and eastern NZ: one on
Monday and another on Thursday, followed by large southerly swells in the
eastern Tasman Sea.
HIGH H1 in Tasman Sea by mid-weak is expected to cross northern NZ on
Thursday and Friday.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
03 December 2023
Bob Blog 3 Dec
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 3 December 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/DBf6tMA0pxw
During November the South Pacific weather pattern was something like the
game called FROGGER (available at froggerclassic.appspot.com/)
With Large trucks being the HIGHS migrating from west to east , from south
of Australia across the Tasman Sea and then stalling east of New Zealand.
The more nimble low systems are like the frogs trying to get from north to
south or south to north sometimes succeeding by sidestepping between the
Highs,
and sometimes being squashed. This rhythm is the typical spring pattern a
mix of pattern and chaos.
However El Nino is kicking in, along with a positive Indian Ocean Dipole.
The combined impact is to make a breeding ground for tropical lows near 5 to
10S and 170 E to 170W.
During November this only activated once around mid-month
And a similar pattern is happening this weekend.
The warmer than normal area that has been around NZ for much of this year is
getting smaller.
Average isobars for past month : The Siberian HIGH has developed quickly in
November. In the Southern Hemisphere, the subtropical ridge has shifted into
the Australian Bight and a heat trough has developed over mainland
Australia.
Pressure anomalies for past month : Falling pressures over Russia and rising
pressures over the roaring 40s in the Southern Hemisphere. Note the tendril
of low pressure from Fiji towards New Zealand,.
Zooming into the NZ area: The 1015 isobar has shifted south across
Australia.
TROPICS
RAMON appeared briefly in the NE Pacific and MICHAUNG is now fading off
India.
Depression92P is building slowly near the Solomon Islands.
It has a twin just north of the equator, defying the rule that rotating
winds are impossible at the equator:
The MJO, a burst of extra energy in the tropics, is expected to enter the
western Pacific over next few weeks.
WEATHER ZONES
The South Pacific Convergence zone is building especially with Tropical
depression 92P near Solomons.
This may become a cyclone and travel SW into Coral Sea, and maybe Tasman Sea
next week. AVOID.
HIGHS and LOWS
HIGH H1 well to east of NZ and south of Tahiti is acting as a block.
It should be replaced by HIGH H2 by end of the week.
LOW L1 crossed North Island on Sunday and is expected to linger to NE of NZ
until mid-week and then travel off to the southeast.
Associated trough is expected to cross Tonga around local Friday.
High H3 should form in Tasman Sea by mid-week and cross central NZ this
weekend.
A trough from Southern Ocean is expected to enter South Tasman Sea by Friday
and cross the South Island on Saturday followed by a trough and southerly
change early next week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 3 December 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/DBf6tMA0pxw
During November the South Pacific weather pattern was something like the
game called FROGGER (available at froggerclassic.appspot.com/)
With Large trucks being the HIGHS migrating from west to east , from south
of Australia across the Tasman Sea and then stalling east of New Zealand.
The more nimble low systems are like the frogs trying to get from north to
south or south to north sometimes succeeding by sidestepping between the
Highs,
and sometimes being squashed. This rhythm is the typical spring pattern a
mix of pattern and chaos.
However El Nino is kicking in, along with a positive Indian Ocean Dipole.
The combined impact is to make a breeding ground for tropical lows near 5 to
10S and 170 E to 170W.
During November this only activated once around mid-month
And a similar pattern is happening this weekend.
The warmer than normal area that has been around NZ for much of this year is
getting smaller.
Average isobars for past month : The Siberian HIGH has developed quickly in
November. In the Southern Hemisphere, the subtropical ridge has shifted into
the Australian Bight and a heat trough has developed over mainland
Australia.
Pressure anomalies for past month : Falling pressures over Russia and rising
pressures over the roaring 40s in the Southern Hemisphere. Note the tendril
of low pressure from Fiji towards New Zealand,.
Zooming into the NZ area: The 1015 isobar has shifted south across
Australia.
TROPICS
RAMON appeared briefly in the NE Pacific and MICHAUNG is now fading off
India.
Depression92P is building slowly near the Solomon Islands.
It has a twin just north of the equator, defying the rule that rotating
winds are impossible at the equator:
The MJO, a burst of extra energy in the tropics, is expected to enter the
western Pacific over next few weeks.
WEATHER ZONES
The South Pacific Convergence zone is building especially with Tropical
depression 92P near Solomons.
This may become a cyclone and travel SW into Coral Sea, and maybe Tasman Sea
next week. AVOID.
HIGHS and LOWS
HIGH H1 well to east of NZ and south of Tahiti is acting as a block.
It should be replaced by HIGH H2 by end of the week.
LOW L1 crossed North Island on Sunday and is expected to linger to NE of NZ
until mid-week and then travel off to the southeast.
Associated trough is expected to cross Tonga around local Friday.
High H3 should form in Tasman Sea by mid-week and cross central NZ this
weekend.
A trough from Southern Ocean is expected to enter South Tasman Sea by Friday
and cross the South Island on Saturday followed by a trough and southerly
change early next week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
26 November 2023
Bob Blog
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 26 November 2023
Earth briefly passed a critical warming threshold on Fri 17 Nov. According
to data from ERA5, the European Centre for Medium-Range Weather Forecasts'
(ECMWF) fifth generation reanalysis of the global climate from 1940 to the
present, 17 November 2023 was the first day in which the global temperature
exceeded 2°C above pre-industrial levels. These latest figures put Earth's
rising temperatures into sharp focus ahead of COP28, which is set to start
in Dubai, United Arab Emirates, on 30 November.
TROPICS
The South Pacific Convergence zone is located from Solomons to Tokelau and
then SE towards Southern Cooks.
HIGHS and LOWS
LOW1 has been east of Gisborne this weekend with southerly rain over NE of
NZ and is moving off to the southeast.
HIGH H1 is remaining quasi stationary around 35S to south of Tahiti, with a
strong ridge along 30S between Fiji and NZ.
LOW L2 off Tasmania by Monday is expected to cross NZ as a trough on Tuesday
followed by a SW flow on Wednesday.
HIGH H2 should follow L2 crossing NZ on Thursday and Friday.
LOW L3 is expected to move from Aussie interior to off NSW by Thursday and
then travel east across the Tasman this weekend and central NZ on Monday.
These are mediocre features this week, nothing to noticeably avoid.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 26 November 2023
Earth briefly passed a critical warming threshold on Fri 17 Nov. According
to data from ERA5, the European Centre for Medium-Range Weather Forecasts'
(ECMWF) fifth generation reanalysis of the global climate from 1940 to the
present, 17 November 2023 was the first day in which the global temperature
exceeded 2°C above pre-industrial levels. These latest figures put Earth's
rising temperatures into sharp focus ahead of COP28, which is set to start
in Dubai, United Arab Emirates, on 30 November.
TROPICS
The South Pacific Convergence zone is located from Solomons to Tokelau and
then SE towards Southern Cooks.
HIGHS and LOWS
LOW1 has been east of Gisborne this weekend with southerly rain over NE of
NZ and is moving off to the southeast.
HIGH H1 is remaining quasi stationary around 35S to south of Tahiti, with a
strong ridge along 30S between Fiji and NZ.
LOW L2 off Tasmania by Monday is expected to cross NZ as a trough on Tuesday
followed by a SW flow on Wednesday.
HIGH H2 should follow L2 crossing NZ on Thursday and Friday.
LOW L3 is expected to move from Aussie interior to off NSW by Thursday and
then travel east across the Tasman this weekend and central NZ on Monday.
These are mediocre features this week, nothing to noticeably avoid.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
19 November 2023
Bob Blog
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 19 November 2023
"Characterization of Microplastics in Clouds over Eastern China"
Environmental Science & Technology Letters
Researchers characterized the properties of microplastics in clouds at the
top of Mount Tai (shown here), finding the particles could play a role in
cloud formation.
Microplastics - plastic fragments smaller than five millimeters - originate
from a myriad of items used daily, such as clothing, packaging and car
tires. As research in the field evolves, scientists are not only detecting
microplastics in the atmosphere but also investigating how they may play a
role in cloud formation. For example, a group of researchers recently
detected plastic granules, which had water-attracting surfaces, in Japanese
mountaintop clouds. So, to learn more, Yan Wang and colleagues set out to
look for microplastics in mountain clouds, used computer models to figure
out how they could have gotten there, and tested how the particles could
have impacted - and been impacted by - the clouds.
Wang and the team first collected 28 samples of liquid from clouds at the
top of Mount Tai in eastern China. Then they analyzed the samples and found:
. Low-altitude and denser clouds contained greater amounts of microplastics.
. Particles were made of common polymers, including polyethylene
terephthalate, polypropylene, polyethylene, polystyrene and polyamide.
. The microplastics tended to be smaller than 100 micrometers in length,
although some were as long as 1,500 micrometers.
. Older, rougher particles had more lead, mercury and oxygen attached to
their surfaces, which the researchers suggest could facilitate cloud
development.
TROPICS
Finally, a weekend with no named storms.
MAL visited NW Fiji with some strong winds and heavy rain, frightening many
yachts into the mangroves, but things quickly returned to normal.
The MJO, a burst of extra energy in the tropics, is now reforming in the
Indian Ocean.
WEATHER ZONES
The South Pacific Convergence zone is located from Solomons to Tokelau and
then SE towards Southern Cooks.
HIGHS and LOWS
HIGH H1 is travelling east along around 50S to east of NZ, blocking the
movement of L1.
It is leaving behind another HIGH H2 in the Tasman Sea which fades away on
Thursday,
LOW L1 is moving off northland on Monday and being pushed off to the NE and
expected to fade by mid-week.
LOW L2 from Sydney area by Tuesday is expected to merge with a low from
Southern Ocean and become a large Low across NZ to east of North Island by
next Saturday with a southerly blast over NZ. Avoid.
This also may bring Southerly swells to 3m as far north as 30S between 170
and 175E in the North Tasman Sea by Saturday. Avoid.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 19 November 2023
"Characterization of Microplastics in Clouds over Eastern China"
Environmental Science & Technology Letters
Researchers characterized the properties of microplastics in clouds at the
top of Mount Tai (shown here), finding the particles could play a role in
cloud formation.
Microplastics - plastic fragments smaller than five millimeters - originate
from a myriad of items used daily, such as clothing, packaging and car
tires. As research in the field evolves, scientists are not only detecting
microplastics in the atmosphere but also investigating how they may play a
role in cloud formation. For example, a group of researchers recently
detected plastic granules, which had water-attracting surfaces, in Japanese
mountaintop clouds. So, to learn more, Yan Wang and colleagues set out to
look for microplastics in mountain clouds, used computer models to figure
out how they could have gotten there, and tested how the particles could
have impacted - and been impacted by - the clouds.
Wang and the team first collected 28 samples of liquid from clouds at the
top of Mount Tai in eastern China. Then they analyzed the samples and found:
. Low-altitude and denser clouds contained greater amounts of microplastics.
. Particles were made of common polymers, including polyethylene
terephthalate, polypropylene, polyethylene, polystyrene and polyamide.
. The microplastics tended to be smaller than 100 micrometers in length,
although some were as long as 1,500 micrometers.
. Older, rougher particles had more lead, mercury and oxygen attached to
their surfaces, which the researchers suggest could facilitate cloud
development.
TROPICS
Finally, a weekend with no named storms.
MAL visited NW Fiji with some strong winds and heavy rain, frightening many
yachts into the mangroves, but things quickly returned to normal.
The MJO, a burst of extra energy in the tropics, is now reforming in the
Indian Ocean.
WEATHER ZONES
The South Pacific Convergence zone is located from Solomons to Tokelau and
then SE towards Southern Cooks.
HIGHS and LOWS
HIGH H1 is travelling east along around 50S to east of NZ, blocking the
movement of L1.
It is leaving behind another HIGH H2 in the Tasman Sea which fades away on
Thursday,
LOW L1 is moving off northland on Monday and being pushed off to the NE and
expected to fade by mid-week.
LOW L2 from Sydney area by Tuesday is expected to merge with a low from
Southern Ocean and become a large Low across NZ to east of North Island by
next Saturday with a southerly blast over NZ. Avoid.
This also may bring Southerly swells to 3m as far north as 30S between 170
and 175E in the North Tasman Sea by Saturday. Avoid.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
17 November 2023
Collaboration request
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12 November 2023
Bob blog
McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 12 November 2023
The November Migration
A snapshot of marine traffic mid last week shows that the November migration
of cruising yachts (coloured orange here) is in full swing. 1 November is
nominally the start of the cyclone season, and yachts are exiting the
tropics. Some are heading for Australia, and many seem lined up for New
Zealand
I've chosen this week to also do a road-trip /migration and will be visiting
Northland. I shall be visiting the Opua Cruising club for dinner on
Wednesday and Thursday evening. I invite any one in this migration who has
recently arrived in Opua to have a chat.
And the migration seems to be timely. There was a equatorial westerly last
week and it is helping to form a twin of spinning spirals neat 150 to 180:
The spinning thunderstorms near 10S 170E have now developed into tropical
depression 91P/02F
The models still are differing about over the future of this system.
I find that good reading of it potential impact is available from the wind
accumulation map selection on windy.com .
The latest OFFICIAL information is issued by Fiji Met Service in their
tropical disturbance notice at www.met.gov.fj/aifs_prods/20032.txt
TROPICS
Apart form the Depression NW of Fiji, there are also others being watched on
the northern side of the equator that were triggered by that equatorial
westerly.
The MJO, a burst of extra energy in the tropics, is now over the western
Pacific for the next few weeks.
WEATHER ZONES
The South Pacific Convergence zone is mainly mixed in with clouds of the
forming Tropical cyclone. The path of the gales is across Fiji mainly on
Tuesday /Wednesday and Minerva on Thursday. Avoid. Those travelling south to
NZ should target to get south of 28S by Thursday.
HIGHS and LOWS
HIGH H1 is travelling east along 35S. There is a squash zone of enhanced
trade winds on its northern side and this seems to be weakening.
There is a trough between Tonga and NZ. Low L1 should form in this trough
near 30S 180 tonight and travel SE this week Combined with a front crossing
NZ on Tuesday this is expected to maintain a southerly flow from NZ to as
far north as 30S until Wednesday.
A front over SW of NZ on Monday is likely to stall, bringing extreme rain.
The next trough and low is expected to cross Tasman Sea and South Island on
Thursday and then stall over North Island on Friday and the weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/ Weathergram with graphics is at
metbob.wordpress.com (subscribe/unsubscribe at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 12 November 2023
The November Migration
A snapshot of marine traffic mid last week shows that the November migration
of cruising yachts (coloured orange here) is in full swing. 1 November is
nominally the start of the cyclone season, and yachts are exiting the
tropics. Some are heading for Australia, and many seem lined up for New
Zealand
I've chosen this week to also do a road-trip /migration and will be visiting
Northland. I shall be visiting the Opua Cruising club for dinner on
Wednesday and Thursday evening. I invite any one in this migration who has
recently arrived in Opua to have a chat.
And the migration seems to be timely. There was a equatorial westerly last
week and it is helping to form a twin of spinning spirals neat 150 to 180:
The spinning thunderstorms near 10S 170E have now developed into tropical
depression 91P/02F
The models still are differing about over the future of this system.
I find that good reading of it potential impact is available from the wind
accumulation map selection on windy.com .
The latest OFFICIAL information is issued by Fiji Met Service in their
tropical disturbance notice at www.met.gov.fj/aifs_prods/20032.txt
TROPICS
Apart form the Depression NW of Fiji, there are also others being watched on
the northern side of the equator that were triggered by that equatorial
westerly.
The MJO, a burst of extra energy in the tropics, is now over the western
Pacific for the next few weeks.
WEATHER ZONES
The South Pacific Convergence zone is mainly mixed in with clouds of the
forming Tropical cyclone. The path of the gales is across Fiji mainly on
Tuesday /Wednesday and Minerva on Thursday. Avoid. Those travelling south to
NZ should target to get south of 28S by Thursday.
HIGHS and LOWS
HIGH H1 is travelling east along 35S. There is a squash zone of enhanced
trade winds on its northern side and this seems to be weakening.
There is a trough between Tonga and NZ. Low L1 should form in this trough
near 30S 180 tonight and travel SE this week Combined with a front crossing
NZ on Tuesday this is expected to maintain a southerly flow from NZ to as
far north as 30S until Wednesday.
A front over SW of NZ on Monday is likely to stall, bringing extreme rain.
The next trough and low is expected to cross Tasman Sea and South Island on
Thursday and then stall over North Island on Friday and the weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/ Weathergram with graphics is at
metbob.wordpress.com (subscribe/unsubscribe at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
05 November 2023
Bob Blog 5 Nov
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 5November 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/z6UHHEhr8Tc
During October the mid-latitudes were a true mix of intrusions form tropics
and polar regions. As is normal in Sprin. This year the sea over the central
equatorial Pacific were warmer than normal and Cyclone LOLA was produced,
briefly Cat 5 near Pentecost Island, The Low rejuvenated when it met cold
southerly winds in the Tasman Sea and brough wet windy conditions to norther
North Island a few days after the COASTAL CLASSIC
At about the same time Cyclone OTIS burst to Cat % as it moved onto
Acapulco:
I can't remember any month in the recent path with two Cat 5 cyclones almost
at the same time in different hemisphere.
Seasonal changes are observable: In the Northern Hemisphere the winter HIGH
has developed over much of Europe. In the Southern Hemisphere, the
subtropical ridge is shifting slowly south.
Pressure anomalies for past month
Shows falling pressures over Russia and rising pressures over the roaring
40s in the Southern Hemisphere.
A detail of interest is that LOLA's rejuvenation in the Tasman Sea has
impacted the anomaly map.
Isobars are getting higher over Australia /NE/and further east. There is
also higher pressure building over eastern Canada. Lower pressures over
southern Indian ocean.
Zooming into the NZ area
The isobars north and south of New Zealand haven't changed much, and
overall, the 1020 isobar covers a smaller area. However, there is a new 1025
isobar west of Perth.
TROPICS
PILAR crossed El Salvidor with downpours and is now travelling NW across the
Paciifc
The MJO, a burst of extra energy in the tropics, is expected to enter the
western Pacific over next few weeks.
WEATHER ZONES
The South Pacific Convergence zone is building between Solomons and Samoa.
There is expected to be a weak passing trough over Tahiti area next weekend.
Topical Low L2 is expected to form between Fiji and Samoa from mid-week and
then creep slowly westwards towards Solomons next week. Avoid.
HIGH H1 east of NZ is acting as a block.
There is a trough between Tonga and NZ. Low L1 should form in this trough
near 30S 180 tonight and travel SE this week Combined with a front crossing
NZ on Tuesday this is expected to maintain a southerly flow from NZ to as
far north as 30S until Wednesday.
HIGH H2 is expected to spread from south of Tasmania to mid Tasman Sea by
mid-week and then travel NE onto northern NZ.
Between H2 and L2 a squash zone of enhanced easterly winds and large swell
is expected to form from Thursday around 15 to 20S.
For arriving in NZ: Light winds this weekend, then a minor front likely
around Tue 14 Nov, then a few good days with westerly winds.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 5November 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/z6UHHEhr8Tc
During October the mid-latitudes were a true mix of intrusions form tropics
and polar regions. As is normal in Sprin. This year the sea over the central
equatorial Pacific were warmer than normal and Cyclone LOLA was produced,
briefly Cat 5 near Pentecost Island, The Low rejuvenated when it met cold
southerly winds in the Tasman Sea and brough wet windy conditions to norther
North Island a few days after the COASTAL CLASSIC
At about the same time Cyclone OTIS burst to Cat % as it moved onto
Acapulco:
I can't remember any month in the recent path with two Cat 5 cyclones almost
at the same time in different hemisphere.
Seasonal changes are observable: In the Northern Hemisphere the winter HIGH
has developed over much of Europe. In the Southern Hemisphere, the
subtropical ridge is shifting slowly south.
Pressure anomalies for past month
Shows falling pressures over Russia and rising pressures over the roaring
40s in the Southern Hemisphere.
A detail of interest is that LOLA's rejuvenation in the Tasman Sea has
impacted the anomaly map.
Isobars are getting higher over Australia /NE/and further east. There is
also higher pressure building over eastern Canada. Lower pressures over
southern Indian ocean.
Zooming into the NZ area
The isobars north and south of New Zealand haven't changed much, and
overall, the 1020 isobar covers a smaller area. However, there is a new 1025
isobar west of Perth.
TROPICS
PILAR crossed El Salvidor with downpours and is now travelling NW across the
Paciifc
The MJO, a burst of extra energy in the tropics, is expected to enter the
western Pacific over next few weeks.
WEATHER ZONES
The South Pacific Convergence zone is building between Solomons and Samoa.
There is expected to be a weak passing trough over Tahiti area next weekend.
Topical Low L2 is expected to form between Fiji and Samoa from mid-week and
then creep slowly westwards towards Solomons next week. Avoid.
HIGH H1 east of NZ is acting as a block.
There is a trough between Tonga and NZ. Low L1 should form in this trough
near 30S 180 tonight and travel SE this week Combined with a front crossing
NZ on Tuesday this is expected to maintain a southerly flow from NZ to as
far north as 30S until Wednesday.
HIGH H2 is expected to spread from south of Tasmania to mid Tasman Sea by
mid-week and then travel NE onto northern NZ.
Between H2 and L2 a squash zone of enhanced easterly winds and large swell
is expected to form from Thursday around 15 to 20S.
For arriving in NZ: Light winds this weekend, then a minor front likely
around Tue 14 Nov, then a few good days with westerly winds.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
29 October 2023
Bob Blog 29 Oct
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 29 Oct 2023
LOLA's rejuvenation
An outbreak of cold air from the Southern Ocean washed over NZ during the
past week and then, over the weekend, met with the remains of LOLA in the
north Tasman Sea
The central pressure of the system dropped from 1008 to 994 in 24 hours, a
drop of 14 hPa near 30S.
This was caused by the extreme temperature/density difference between the
air for the north and the air from the South. The process is called rapid
cyclogenesis. This is why one of the rules for sailing from Fiji to New
Zealand is "Do not go south with a falling barometer."
TROPICS
TAMMY is now in the North Atlantic after soaking the NE Caribbean, and the
depression 19-E is off the west of Mexico.
Last week LOLA was briefly Cat5 near Pentecost Island. OTIS was briefly Cat
5 near Acapulco. HARMOON caused a quarter of million people to evacuate
into shelters in southern Bangladesh. NORMA is near Baja California and
TAMMY is near the Caribbean. TEJ I flooded pasts of Yemen.
Meteorologists were slammed in the media for the jump to Category 5 by OTIS
See tinyurl.com/CycloneOtis
This idea of shooting the messenger in the media and slamming forecasters
seems to be becoming a trend. MetService issued a review of its performance
in a few major events in NZ last summer see tinyurl.com/MetServiceGabrielle
. One thing the media have not been reporting is that although the computer
models sometimes behave poorly, manual forecasters manage to add value by
issuing warnings that work in saving lives. Insurance companies have noted
that even though the amount of weather damage they have to pay out for is
rising with climate change, the death toll from weather is falling.
WEATHER ZONES
The South Pacific Convergence zone is expected to stay from Solomons to
Samoa. A trough is expected to cross the Minerva area on local Tuesday
followed by a lull.
HIGHS and LOWS
HIGH H1 crossing southern NZ tonight is moving off to the east along 40S.
LOW L1 is travelling southeast and sideswiping the northeast of North Island
on Monday then fading away, leaving behind a lull.
There is a strong squash zone between H1 and L1. Avoid.
LOW L2 is expected to form in central Tasman Sea by mid-week and then fade
across central NZ by the weekend, followed by a SW flow.
The scene is set for southerly winds over northern NZ from 6 to 9 Nov
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 29 Oct 2023
LOLA's rejuvenation
An outbreak of cold air from the Southern Ocean washed over NZ during the
past week and then, over the weekend, met with the remains of LOLA in the
north Tasman Sea
The central pressure of the system dropped from 1008 to 994 in 24 hours, a
drop of 14 hPa near 30S.
This was caused by the extreme temperature/density difference between the
air for the north and the air from the South. The process is called rapid
cyclogenesis. This is why one of the rules for sailing from Fiji to New
Zealand is "Do not go south with a falling barometer."
TROPICS
TAMMY is now in the North Atlantic after soaking the NE Caribbean, and the
depression 19-E is off the west of Mexico.
Last week LOLA was briefly Cat5 near Pentecost Island. OTIS was briefly Cat
5 near Acapulco. HARMOON caused a quarter of million people to evacuate
into shelters in southern Bangladesh. NORMA is near Baja California and
TAMMY is near the Caribbean. TEJ I flooded pasts of Yemen.
Meteorologists were slammed in the media for the jump to Category 5 by OTIS
See tinyurl.com/CycloneOtis
This idea of shooting the messenger in the media and slamming forecasters
seems to be becoming a trend. MetService issued a review of its performance
in a few major events in NZ last summer see tinyurl.com/MetServiceGabrielle
. One thing the media have not been reporting is that although the computer
models sometimes behave poorly, manual forecasters manage to add value by
issuing warnings that work in saving lives. Insurance companies have noted
that even though the amount of weather damage they have to pay out for is
rising with climate change, the death toll from weather is falling.
WEATHER ZONES
The South Pacific Convergence zone is expected to stay from Solomons to
Samoa. A trough is expected to cross the Minerva area on local Tuesday
followed by a lull.
HIGHS and LOWS
HIGH H1 crossing southern NZ tonight is moving off to the east along 40S.
LOW L1 is travelling southeast and sideswiping the northeast of North Island
on Monday then fading away, leaving behind a lull.
There is a strong squash zone between H1 and L1. Avoid.
LOW L2 is expected to form in central Tasman Sea by mid-week and then fade
across central NZ by the weekend, followed by a SW flow.
The scene is set for southerly winds over northern NZ from 6 to 9 Nov
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
22 October 2023
Bob Blog 22 Oct
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 22 Oct 2023
LOLA's origins
Last week we looked at the Australian and South Pacific Cyclone outlooks for
the coming season. In my "what to avoid" summary I concluded that "Low L3
is expected to deepen over northern Vanuatu next week and maybe travel SW
into Coral Sea. Avoid this next week."
Well "Low 3" has now been named LOLA
and is the first cyclone of the new season that nominally starts on
1November.
LOLA was named ten days before season start. Why so early?
Looking at the satellite imagery, It seems that LOLA follows the normal
recipe for cyclone cooking.
1. Heat the sea to over 26C
2. Add lots of moisture a gang of tropical squally thunderstorms
3. And spin. As the gang of thunderstorms tumble together, they create
an area where air is vented up and outwards faster than it can be drawn in
from the fringes.
4. The central pressure drops, making more isobars on the weather map,
making a faster spin. This continues as long as the system has warm sea
and moist air to feed on.
Looking at the streamlines ...
.. It seems that the centre of action that has allowed LOLA to form is
related to the warm water over the central Pacific. Prior to its formation
there was a zone of equatorial westerlies all by itself near the dateline.
not an extension of the Asian monsoon. LOLA formed with an equatorial twin
thanks to those equatorial westerlies. So, it formed around 5S, very close
to the equator, an unusual spot for a South Pacific Cyclone -- these
usually form on the South Pacific Convergence zone. This may be related to
El Nino. It is associated with a shift of the Walker cell into the central
Pacific, especially when combined with a positive Indian Dipole.
See https://tinyurl.com/hadleywalker
So, 2023 is an El Nino year with an active zone near the equator. The same
pattern happened in 1972 and helped form TC BEBE 19th-29th October. It also
formed near 5S.
TROPICS
NORMA is near Baja California and TAMMY is near the Caribbean .TEJ is making
landfall over Yemen And LOLA is deepening as it approaches Vanuatu..
WEATHER ZONES
A lot to avoid this week.
The South Pacific Convergence zone is expected to stay from Solomons to
LOLA. Another branch is expected to linger north of Fiji to Samoa. A trough
should linger from Southern Cooks to south of Tahiti. LOLA is expected to
deepen as it moves slowly south near Vanuatu and peak at category 3 by
Wednesday then travel south or southeast maybe towards NZ next weekend.
Avoid.
HIGHS and LOWS
Low L1 east of NZ is expected to travel east.
HIGH H1 over NZ is expected to follow L1.
Trough is expected to roll northeastwards across the Tasman Sea followed by
strong SE winds and southerly swells up to 5m. Should reach from Bundaberg
to Northland by Friday. Avoid.
This is followed by a HIGH that stretches from central Tasman Sea to South
Island by next weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 22 Oct 2023
LOLA's origins
Last week we looked at the Australian and South Pacific Cyclone outlooks for
the coming season. In my "what to avoid" summary I concluded that "Low L3
is expected to deepen over northern Vanuatu next week and maybe travel SW
into Coral Sea. Avoid this next week."
Well "Low 3" has now been named LOLA
and is the first cyclone of the new season that nominally starts on
1November.
LOLA was named ten days before season start. Why so early?
Looking at the satellite imagery, It seems that LOLA follows the normal
recipe for cyclone cooking.
1. Heat the sea to over 26C
2. Add lots of moisture a gang of tropical squally thunderstorms
3. And spin. As the gang of thunderstorms tumble together, they create
an area where air is vented up and outwards faster than it can be drawn in
from the fringes.
4. The central pressure drops, making more isobars on the weather map,
making a faster spin. This continues as long as the system has warm sea
and moist air to feed on.
Looking at the streamlines ...
.. It seems that the centre of action that has allowed LOLA to form is
related to the warm water over the central Pacific. Prior to its formation
there was a zone of equatorial westerlies all by itself near the dateline.
not an extension of the Asian monsoon. LOLA formed with an equatorial twin
thanks to those equatorial westerlies. So, it formed around 5S, very close
to the equator, an unusual spot for a South Pacific Cyclone -- these
usually form on the South Pacific Convergence zone. This may be related to
El Nino. It is associated with a shift of the Walker cell into the central
Pacific, especially when combined with a positive Indian Dipole.
See https://tinyurl.com/hadleywalker
So, 2023 is an El Nino year with an active zone near the equator. The same
pattern happened in 1972 and helped form TC BEBE 19th-29th October. It also
formed near 5S.
TROPICS
NORMA is near Baja California and TAMMY is near the Caribbean .TEJ is making
landfall over Yemen And LOLA is deepening as it approaches Vanuatu..
WEATHER ZONES
A lot to avoid this week.
The South Pacific Convergence zone is expected to stay from Solomons to
LOLA. Another branch is expected to linger north of Fiji to Samoa. A trough
should linger from Southern Cooks to south of Tahiti. LOLA is expected to
deepen as it moves slowly south near Vanuatu and peak at category 3 by
Wednesday then travel south or southeast maybe towards NZ next weekend.
Avoid.
HIGHS and LOWS
Low L1 east of NZ is expected to travel east.
HIGH H1 over NZ is expected to follow L1.
Trough is expected to roll northeastwards across the Tasman Sea followed by
strong SE winds and southerly swells up to 5m. Should reach from Bundaberg
to Northland by Friday. Avoid.
This is followed by a HIGH that stretches from central Tasman Sea to South
Island by next weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
15 October 2023
Bob Blog 15 Oct
Bob Blog 15 Oct
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 15 Oct 2023
The Cyclone Outlook for the coming season:
Gilbert Walker was an applied mathematician at the University of Cambridge
when he became director-general of observatories in India in 1904. While
there, he studied the characteristics of the Indian Ocean monsoon, the
failure of whose rains had brought severe famine to the country in 1899.
Analysing vast amounts of weather data from India and the rest of the world,
over the next fifteen years he published the first descriptions of the great
seesaw oscillation of atmospheric pressure between the Indian and Pacific
Ocean, and its correlation to temperature and rainfall patterns across much
of the Earth's tropical regions, including India. One of his identified
oscillations has been named the Southern Oscillation and Walker worked with
the Indian Meteorological Department studying the link between the monsoon
and Southern Oscillation phenomenon. He was made a Companion of the Order of
the Star of India in 1911.
Image shows a normal Walker circulation as a conceptual zone of rising air
over Australia and sinking air over Peru. aloo shows a reversed Walker as it
is now during an El Nino event with sinking air over Australia (dry) (see
Oceanreview.com))
The Walker circulation over the Indian ocean is known as the Indian Ocean
Diopole. This is having a positive phase at present, also bringing sinking
dry air over Australia. (from study iq.com).
Thanks to the combination of an El Nino and a positive Indian Dipole,
Australia is being dealt dry sinking air from both the Pacific and the
Indian Oceans. Australia's Bureau of Met have issued their Cyclone outlook
for the coming season with the summary:
Below average number of tropical cyclones is likely for Australia in 2023-24
And in New Zealand the combined resources of NIWA and MetService have issued
a map of expected cyclone numbers:
Using analogue years 73/73,83/83,02/03,04/05, and09/10 and going for reduced
risk near Australia, normal to elevated risk between Tuvalu and Tahiti, and
elevated risk for Vanuatu, Fiji and Northern Cooks.
See://niwa.co.nz/sites/niwa.co.nz/files/tc_outlook_2023-24.pdf
TROPICS
SEAN is travelling to the northwest across he North Atlantic.
WEATHER ZONES
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Tuvalu. There is expected to be a passing trough over
Southern Cooks and Tahiti around mid-week helping Island -hopping from
Tahiti to Tuamotu Islands.
HIGHS and LOWS
HIGH H1 east of NZ is expected to travel slowly eastwards along 35 to 40S.
LOW L1 is expected to roll in from SW of Tasmania and go NE and deepen in
the Tasman Sea on Tuesday. Associated warm front should stall around
northern NZ on Wednesday and Thursday with strong NE to E winds. Low is then
expected to weaken into a trough reaching Fiji and Tonga over the weekend.
Low L3 is expected to deepen over northern Vanuatu next week and maybe
travel SW into Coral Sea. Avoid this next week
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 15 Oct 2023
The Cyclone Outlook for the coming season:
Gilbert Walker was an applied mathematician at the University of Cambridge
when he became director-general of observatories in India in 1904. While
there, he studied the characteristics of the Indian Ocean monsoon, the
failure of whose rains had brought severe famine to the country in 1899.
Analysing vast amounts of weather data from India and the rest of the world,
over the next fifteen years he published the first descriptions of the great
seesaw oscillation of atmospheric pressure between the Indian and Pacific
Ocean, and its correlation to temperature and rainfall patterns across much
of the Earth's tropical regions, including India. One of his identified
oscillations has been named the Southern Oscillation and Walker worked with
the Indian Meteorological Department studying the link between the monsoon
and Southern Oscillation phenomenon. He was made a Companion of the Order of
the Star of India in 1911.
Image shows a normal Walker circulation as a conceptual zone of rising air
over Australia and sinking air over Peru. aloo shows a reversed Walker as it
is now during an El Nino event with sinking air over Australia (dry) (see
Oceanreview.com))
The Walker circulation over the Indian ocean is known as the Indian Ocean
Diopole. This is having a positive phase at present, also bringing sinking
dry air over Australia. (from study iq.com).
Thanks to the combination of an El Nino and a positive Indian Dipole,
Australia is being dealt dry sinking air from both the Pacific and the
Indian Oceans. Australia's Bureau of Met have issued their Cyclone outlook
for the coming season with the summary:
Below average number of tropical cyclones is likely for Australia in 2023-24
And in New Zealand the combined resources of NIWA and MetService have issued
a map of expected cyclone numbers:
Using analogue years 73/73,83/83,02/03,04/05, and09/10 and going for reduced
risk near Australia, normal to elevated risk between Tuvalu and Tahiti, and
elevated risk for Vanuatu, Fiji and Northern Cooks.
See://niwa.co.nz/sites/niwa.co.nz/files/tc_outlook_2023-24.pdf
TROPICS
SEAN is travelling to the northwest across he North Atlantic.
WEATHER ZONES
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Tuvalu. There is expected to be a passing trough over
Southern Cooks and Tahiti around mid-week helping Island -hopping from
Tahiti to Tuamotu Islands.
HIGHS and LOWS
HIGH H1 east of NZ is expected to travel slowly eastwards along 35 to 40S.
LOW L1 is expected to roll in from SW of Tasmania and go NE and deepen in
the Tasman Sea on Tuesday. Associated warm front should stall around
northern NZ on Wednesday and Thursday with strong NE to E winds. Low is then
expected to weaken into a trough reaching Fiji and Tonga over the weekend.
Low L3 is expected to deepen over northern Vanuatu next week and maybe
travel SW into Coral Sea. Avoid this next week
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
08 October 2023
Bob Blog 8 Oct 23
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 8 Oct 2023
Island Climate Update
NIWA have issued their October edition of the Island Climate Update
available online as a pdf at niwa.co.nz/climate/island-climate-update.
Now that we are having El Nino this page gives us a look at what that may
mean for rainfall and drought/water stress over the next few months.
On this page there is also access to a selection of maps for various
locations the recent conditions, and Outlooks for various periods.
Amongst these I found the following to be most interesting:
During the past month there was less than 40mm of rain over Tonga ,, and
this has resulted in an area of severe water stress there as shown in the
recent water stress map.
Interestingly this region is expected to quickly recover during October:
The prospects for rain between now and December show only a narrow zone of
"near normal", a very wet equatorial zone and a tendency for dryness away
from the equator.
The "normal" pattern needs to be considered along with this map to turn it
into a rainfall map. However, this map gives an indication to what is
physically different. the Hadley cell is being distorted by an extra boost
of upward motion mainly along equator near the dateline and as this air
lifts to the top f the troposphere it is deflected away from the equator and
descends/dries out until it find =s the surface again around 25 north or
south.
TROPICS
KOINU (Japanese for "puppy") produced a measured wind of 213mph and then
destroyed the anemometer at Lanyu Island - that's the third highest
land-based measured wind gust. BOLAVEN is expected to stay out to sea east
of Japan. LIDIA and 16E are fading.
WEATHER ZONES
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Samoa/Northern Tonga. There is expected to be a
passing trough over Southern Cooks and Austral Islands after mid-week.
HIGHS and LOWS
LOW L1 east of NZ has some large southerly swells as far north as Fiji on
Monday. It is expected to move off to the SE allowing HIGH H1 to spread
slowly into Tasman Sea and then along 30S past the north of NZ on Friday
13th This HIGH has brought a squash zone in the Coral Sea for a few days and
is bringing good conditions for sailing from tropics to NZ or Aus this week.
The next Low following H1 is expected to bring a warm front and northerly
winds to Northland early next week and then to travel east along 30S
followed by a burst of large southerly swells mid next week. Avoid arriving
in Northland around 18/19 Oct.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 8 Oct 2023
Island Climate Update
NIWA have issued their October edition of the Island Climate Update
available online as a pdf at niwa.co.nz/climate/island-climate-update.
Now that we are having El Nino this page gives us a look at what that may
mean for rainfall and drought/water stress over the next few months.
On this page there is also access to a selection of maps for various
locations the recent conditions, and Outlooks for various periods.
Amongst these I found the following to be most interesting:
During the past month there was less than 40mm of rain over Tonga ,, and
this has resulted in an area of severe water stress there as shown in the
recent water stress map.
Interestingly this region is expected to quickly recover during October:
The prospects for rain between now and December show only a narrow zone of
"near normal", a very wet equatorial zone and a tendency for dryness away
from the equator.
The "normal" pattern needs to be considered along with this map to turn it
into a rainfall map. However, this map gives an indication to what is
physically different. the Hadley cell is being distorted by an extra boost
of upward motion mainly along equator near the dateline and as this air
lifts to the top f the troposphere it is deflected away from the equator and
descends/dries out until it find =s the surface again around 25 north or
south.
TROPICS
KOINU (Japanese for "puppy") produced a measured wind of 213mph and then
destroyed the anemometer at Lanyu Island - that's the third highest
land-based measured wind gust. BOLAVEN is expected to stay out to sea east
of Japan. LIDIA and 16E are fading.
WEATHER ZONES
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Samoa/Northern Tonga. There is expected to be a
passing trough over Southern Cooks and Austral Islands after mid-week.
HIGHS and LOWS
LOW L1 east of NZ has some large southerly swells as far north as Fiji on
Monday. It is expected to move off to the SE allowing HIGH H1 to spread
slowly into Tasman Sea and then along 30S past the north of NZ on Friday
13th This HIGH has brought a squash zone in the Coral Sea for a few days and
is bringing good conditions for sailing from tropics to NZ or Aus this week.
The next Low following H1 is expected to bring a warm front and northerly
winds to Northland early next week and then to travel east along 30S
followed by a burst of large southerly swells mid next week. Avoid arriving
in Northland around 18/19 Oct.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
01 October 2023
Bob Blog 1 Oct
Bob Blog 1 October
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 1 Oct 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/ryMmaz_BxdY
September was a month with several spring fronts across the Tasman Sea.
These fronts were more mobile than in July and August so brought no
lingering damage. Mobile HIGHS are now on the weather map crossing the north
Tasman Sea. In the last week of the month meteorologists conformed that
parameters are now at El Nino level, also a positive Indian Ocean Dipole (El
Nino's Indian Ocean cousin). These events combine to deprive rain over
Australia, especially SE Australia. This has already led to two brief heat
waves over SE Australia.
Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml
In the Sea temperature anomalies, there is a build -p of high temps south of
Tahiti. And the warm conditions that were near the west coast of North
America have shifted westwards.
In the Northern Hemisphere winter HIGH over northern Europe has built
quickly indicating strong autumn conditions. In the Southern Hemisphere, the
subtropical ridges are slowly
Isobars are getting higher over Australia /NE/and further east. There is
also higher pressure building over eastern Canada. Lower pressures over
southern Indian ocean.
There is a widening of the subtropical ridge over NZ. A slight southward
shift. Slightly more westerly gradient over NZ,
TROPICS
Storm surge for weakening OPHELIA flooded parts of North Carolina. NIGEL
faded on its way to Europe and is followed by PHILLIPE and RINA. KOINUI is
skirting past north of Philippines.
The MJO, a burst of extra energy in the tropics, is weakly crossing New
Guinea
WEATHER ZONES
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Samoa/Northern Tonga. There is expected to be a
passing trough over Southern Cooks and Austral Islands after mid-week. Be
Aware.
HIGH H1 north of NZ tonight is moving steadily along 30S with a small squash
zone and a burst of southerly swell on its northern side.
Trough associated with Low L1 is crossing NZ on Monday followed by cold
Southerly winds on Tuesday.
HIGH H2 is expected to travel NE across the Tasman Sea and linger around
northern NZ on Thursday and Friday.
Trough associated t=with L2 is expected to reach from New Caledonia to New
Zealand by Saturday, affecting anyone sailing across North Tasman Sea this
week.
Tropics to NZ: avoid arriving in NZ on Sun 8 October.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 1 Oct 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/ryMmaz_BxdY
September was a month with several spring fronts across the Tasman Sea.
These fronts were more mobile than in July and August so brought no
lingering damage. Mobile HIGHS are now on the weather map crossing the north
Tasman Sea. In the last week of the month meteorologists conformed that
parameters are now at El Nino level, also a positive Indian Ocean Dipole (El
Nino's Indian Ocean cousin). These events combine to deprive rain over
Australia, especially SE Australia. This has already led to two brief heat
waves over SE Australia.
Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml
In the Sea temperature anomalies, there is a build -p of high temps south of
Tahiti. And the warm conditions that were near the west coast of North
America have shifted westwards.
In the Northern Hemisphere winter HIGH over northern Europe has built
quickly indicating strong autumn conditions. In the Southern Hemisphere, the
subtropical ridges are slowly
Isobars are getting higher over Australia /NE/and further east. There is
also higher pressure building over eastern Canada. Lower pressures over
southern Indian ocean.
There is a widening of the subtropical ridge over NZ. A slight southward
shift. Slightly more westerly gradient over NZ,
TROPICS
Storm surge for weakening OPHELIA flooded parts of North Carolina. NIGEL
faded on its way to Europe and is followed by PHILLIPE and RINA. KOINUI is
skirting past north of Philippines.
The MJO, a burst of extra energy in the tropics, is weakly crossing New
Guinea
WEATHER ZONES
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Samoa/Northern Tonga. There is expected to be a
passing trough over Southern Cooks and Austral Islands after mid-week. Be
Aware.
HIGH H1 north of NZ tonight is moving steadily along 30S with a small squash
zone and a burst of southerly swell on its northern side.
Trough associated with Low L1 is crossing NZ on Monday followed by cold
Southerly winds on Tuesday.
HIGH H2 is expected to travel NE across the Tasman Sea and linger around
northern NZ on Thursday and Friday.
Trough associated t=with L2 is expected to reach from New Caledonia to New
Zealand by Saturday, affecting anyone sailing across North Tasman Sea this
week.
Tropics to NZ: avoid arriving in NZ on Sun 8 October.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
24 September 2023
Bob Blog
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 24 Sep 2023
DAYLIGHT SAVING
The number of countries that mark daylight saving time is slowly decreasing,
but it is still observed in Australia and New Zealand.
Ne
In Australia, saving is observed in New South Wales, Victoria, South
Australia, Tasmania, the Australian Capital Territory and Norfolk Island.
These places start next Sunday, 1 October, the first Sunday in October.
Daylight Saving Time continues in these places until the first Sunday in
April (3am Daylight time ->2am standard time), 7 April 2024.
TROPICS
Former cyclone LEE knocked out power over Canada's maritime provinces.
Ophelia made landfall over Northern Carolina.
WEATHER ZONES
The South Pacific Convergence zone is building over Solomon Islands to
Tuvalu to Tokelau , with an active trough/convergence zone from near
Suwarrow to over Tahiti. An MJO , or burst of tropical energy is expected to
move onto Coral Sea and Micronesia zone over next few weeks.
HIGHS and LOWS:
HIGH H1 Is intense and moving slowly along 35S well east of NZ. It has been
blocking the front over NZ, slowing the movement of its rain. around 400mm
of rain is expected for the Eastern ranges of North Island next two days.
LOW L1 is expected to form north of NZ by Monday in the trough on the back
of H! L1 is expected to travel south across eastern NZ next few days. Avoid.
Low L2 is expected to travel NE into the central Tasman Sea by mid-week and
then weaken crossing North Island on Thursday. Another Front from the SW is
expected to deepen into a low over central NZ this weekend. Avoid/
In tandem with L2 Highs H2 and H3 should form of the Australian coast on
Tuesday and Thursday then fade as they go NE. Another HIGH should follow the
weekend front and then settle near North Island next week.
Avoid arriving in Northland on Thursday and Saturday this coming week. Looks
OK anytime next week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 24 Sep 2023
DAYLIGHT SAVING
The number of countries that mark daylight saving time is slowly decreasing,
but it is still observed in Australia and New Zealand.
Ne
In Australia, saving is observed in New South Wales, Victoria, South
Australia, Tasmania, the Australian Capital Territory and Norfolk Island.
These places start next Sunday, 1 October, the first Sunday in October.
Daylight Saving Time continues in these places until the first Sunday in
April (3am Daylight time ->2am standard time), 7 April 2024.
TROPICS
Former cyclone LEE knocked out power over Canada's maritime provinces.
Ophelia made landfall over Northern Carolina.
WEATHER ZONES
The South Pacific Convergence zone is building over Solomon Islands to
Tuvalu to Tokelau , with an active trough/convergence zone from near
Suwarrow to over Tahiti. An MJO , or burst of tropical energy is expected to
move onto Coral Sea and Micronesia zone over next few weeks.
HIGHS and LOWS:
HIGH H1 Is intense and moving slowly along 35S well east of NZ. It has been
blocking the front over NZ, slowing the movement of its rain. around 400mm
of rain is expected for the Eastern ranges of North Island next two days.
LOW L1 is expected to form north of NZ by Monday in the trough on the back
of H! L1 is expected to travel south across eastern NZ next few days. Avoid.
Low L2 is expected to travel NE into the central Tasman Sea by mid-week and
then weaken crossing North Island on Thursday. Another Front from the SW is
expected to deepen into a low over central NZ this weekend. Avoid/
In tandem with L2 Highs H2 and H3 should form of the Australian coast on
Tuesday and Thursday then fade as they go NE. Another HIGH should follow the
weekend front and then settle near North Island next week.
Avoid arriving in Northland on Thursday and Saturday this coming week. Looks
OK anytime next week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
17 September 2023
Bob Gram 17 Sep
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 17Sep 2023
The incoming El Nino is starting to show its colours.
El Nino is the name given to the period when sea surface temperature SST
over the eastern equatorial Pacific is above normal. (La Nina is the name
given when sea temperature are cooler).
In the atmosphere we monitor ENSO = El Nino/Southern Oscillation and its
impact on the weather map by using. the Southern Oscillation Index SOI (30
day running mean). This is based on the standardized difference in the
barometer readings between Tahiti and Darwin, in other words it counts the
average number of isobars between them on the weather map. When the index
stays below -10 (on the scale shown here) for more than a month we call it
an EL NINO event.
And recent data is showing we are now in El Nino territory.
The Ocean:
The parameter used from the ocean is based on the sea surface temperatures
in the equatorial eastern Pacific and called the NINO 3.4 SST anomaly.
International research Institute IRI have compiled the predictions for all
the models as shown here from iri.columbia.edu. The consensus is that
NINO3.4 will peak during NDJ= November, December, January. A strong El Nino
for the coming Summer.
Expected impact in the South Pacific
An El Nino is associated with weaker trade winds, and this tends to shift
the subtropical ridge north allowing for stronger westerly winds south of
40S. The peak cyclone prone area shifts from Vanuatu towards the dateline.
In New Zealand the stronger westerly winds from the Tasman Sea arrive cool
and moist onto the western side of the main divide. They are deflected
upwards dropping their ample rains and filling up the hydro lakes. These
winds then descend across the plains on the east coast hot and dry due to
the foehn effect. In seems likely that by the end of the year eastern New
Zealand (and lots of SE Australia) will be ripe for bush fires.
However, each El Nino event is different and even a strong El Nino only
explains around 20% of the observed weather variance.
I asked Chat Gpt to turn that into a poem and it came up with the following:
Amidst New Zealand's land of pristine grace,
El Niño's touch, a climatic dance we trace.
From Tasman Sea, cool, moist winds do rise,
To fill our lakes, a watery, sweet surprise.
They sweep o'er mountains, their path deflects,
As foehn effect, along the east, reflects.
Hot, dry winds now kiss the coastal land,
In El Niño's sway, a shifting, arid brand.
Yet, in this struggle with the altered wind,
New Zealand's spirit, strong, will not rescind,
For though El Niño tests our land anew,
Our hearts and hope endure, forever true.
Hmm, somewhat flowery and disjointed I think.
TROPICS
Central Japan was drenched by slow-moving Tropical Storm Yun-yeung.
Hurricane Lee faded away as Hurricane MARGOT and NIGEL churned the central
Atlantic.
Depression TWELVE-E is moving west across central north Pacific.
WEATHER ZONES
The South Pacific Convergence zone is well north of normal from Solomons to
Tuvalu and there is an extension zone lingering across roughly from Suwarrow
to Tahiti.
HIGHS and LOWS:
HIGH H1 Is intense and moving slowly along 30 to 40S crossing northern NZ on
Tuesday and Wednesday. It has an intense SQUASH ZONE on its norther side
between the Cooks and Fiji from 25S to 12S and along 22S from south of Fiji
to east of New Caledonia. Avoid.
When H1 moves off to the east later this week there should be an easing of
the SE winds in he Coral Sea.
There is disturbed westerly flow over TSMAN SEA /NZ area south of around
38S. This doesn't interfere much with arrivals in Northland, except for
maybe some strong northerly winds there on Saturday 23 Sep with a passing
front.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 17Sep 2023
The incoming El Nino is starting to show its colours.
El Nino is the name given to the period when sea surface temperature SST
over the eastern equatorial Pacific is above normal. (La Nina is the name
given when sea temperature are cooler).
In the atmosphere we monitor ENSO = El Nino/Southern Oscillation and its
impact on the weather map by using. the Southern Oscillation Index SOI (30
day running mean). This is based on the standardized difference in the
barometer readings between Tahiti and Darwin, in other words it counts the
average number of isobars between them on the weather map. When the index
stays below -10 (on the scale shown here) for more than a month we call it
an EL NINO event.
And recent data is showing we are now in El Nino territory.
The Ocean:
The parameter used from the ocean is based on the sea surface temperatures
in the equatorial eastern Pacific and called the NINO 3.4 SST anomaly.
International research Institute IRI have compiled the predictions for all
the models as shown here from iri.columbia.edu. The consensus is that
NINO3.4 will peak during NDJ= November, December, January. A strong El Nino
for the coming Summer.
Expected impact in the South Pacific
An El Nino is associated with weaker trade winds, and this tends to shift
the subtropical ridge north allowing for stronger westerly winds south of
40S. The peak cyclone prone area shifts from Vanuatu towards the dateline.
In New Zealand the stronger westerly winds from the Tasman Sea arrive cool
and moist onto the western side of the main divide. They are deflected
upwards dropping their ample rains and filling up the hydro lakes. These
winds then descend across the plains on the east coast hot and dry due to
the foehn effect. In seems likely that by the end of the year eastern New
Zealand (and lots of SE Australia) will be ripe for bush fires.
However, each El Nino event is different and even a strong El Nino only
explains around 20% of the observed weather variance.
I asked Chat Gpt to turn that into a poem and it came up with the following:
Amidst New Zealand's land of pristine grace,
El Niño's touch, a climatic dance we trace.
From Tasman Sea, cool, moist winds do rise,
To fill our lakes, a watery, sweet surprise.
They sweep o'er mountains, their path deflects,
As foehn effect, along the east, reflects.
Hot, dry winds now kiss the coastal land,
In El Niño's sway, a shifting, arid brand.
Yet, in this struggle with the altered wind,
New Zealand's spirit, strong, will not rescind,
For though El Niño tests our land anew,
Our hearts and hope endure, forever true.
Hmm, somewhat flowery and disjointed I think.
TROPICS
Central Japan was drenched by slow-moving Tropical Storm Yun-yeung.
Hurricane Lee faded away as Hurricane MARGOT and NIGEL churned the central
Atlantic.
Depression TWELVE-E is moving west across central north Pacific.
WEATHER ZONES
The South Pacific Convergence zone is well north of normal from Solomons to
Tuvalu and there is an extension zone lingering across roughly from Suwarrow
to Tahiti.
HIGHS and LOWS:
HIGH H1 Is intense and moving slowly along 30 to 40S crossing northern NZ on
Tuesday and Wednesday. It has an intense SQUASH ZONE on its norther side
between the Cooks and Fiji from 25S to 12S and along 22S from south of Fiji
to east of New Caledonia. Avoid.
When H1 moves off to the east later this week there should be an easing of
the SE winds in he Coral Sea.
There is disturbed westerly flow over TSMAN SEA /NZ area south of around
38S. This doesn't interfere much with arrivals in Northland, except for
maybe some strong northerly winds there on Saturday 23 Sep with a passing
front.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
10 September 2023
Bob Blog 10 Sep 23
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 10 Sep 2023
The MJO
The MJO or Madden Julian Oscillation is the name for a bust of convection in
the tropics that travels eastwards around the equator from Indian Ocean to
Pacific Ocean. Its passage over any one place takes around a week and the
full journey from Indian to Pacific takes around 4 to 6 weeks. It's boost of
extra energy is associated with triggering tropical cyclones. Therefore, it
provides a forecasting tool.
The data shows an MJO over the Coral Sea during the coming week.
But the data description is rather complicated and can be off-putting to
non-meteorologists:
One of my regular readers added this to his blog at
https://twoatsea.com/mjo-who/
>>>>>>>>>>>>>>>>>>>
I was trying learn more about the MJO as it's coming to visit us in
Indonesia this week. I went to NOAA's website about the MJO and immediately
stumbled into this very confusing paragraph.
Forecast of MJO associated anomalous OLR for the next 15 days from the
ensemble mean GFS based on forecasts of RMM1 and RMM2. Blue (yellow/red)
shades show negative (positive) OLR anomalies and enhanced (suppressed)
convection. Forecasts do not include direct contributions from other climate
modes such as ENSO, monsoons, etc. - only the MJO.
I'm positive (negative) that I don't (do) understand, so I asked ChatGPT the
following:
I don't understand this paragraph. Can you explain it to me like I'm 5?
And Chat came to my rescue:
Of course! Let's break it down:
Imagine the Earth has a big weather "dance" going on. This dance has
different moves or patterns that change the weather. One of these dance
moves is called the MJO.
Now, scientists have a special tool (like a magic crystal ball) called the
GFS. This tool tries to guess what the MJO dance move will look like in the
next 15 days. But it's not just one guess; they make many guesses and then
take an average, which they call the "ensemble mean."
To understand the dance move better, they look at two things: RMM1 and RMM2.
Think of these as two special clues that help them guess the MJO dance move.
Now, for the colors:
Blue means there will be more clouds and rain (they call this "enhanced
convection").
Yellow or red means there will be fewer clouds and less rain (they call this
"suppressed convection").
Lastly, even though there are many other dance moves (like ENSO or monsoons)
that can change the weather, this guess is only about the MJO dance move.
They're not looking at the other moves right now.
So, in simple words, scientists are using a tool to guess how a specific
weather pattern (MJO) will change the clouds and rain in the next 15 days.
Blue means more rain, and yellow/red means less rain. And they're only
focusing on this one pattern, not the others.
-Rich
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Inspired by the idea of using Chat GPT to rewrite the MJO description I
asked it to turn its answer into a sonnet:
MJO, a rhythmic dance in the sky,
Like music playing, way up high.
It's like a big wave, moving through the air,
Bringing changes, everywhere it dares.
Imagine clouds, like fluffy cotton candy,
They gather and move, just like a trolley.
MJO makes them dance and sway,
Sometimes it brings rain, other times a sunny day.
It travels along the equator and the tropics,
From the Indian Ocean to the Western Pacific.
It's a weather pattern, you see,
That affects the world, including you and me.
So, MJO is like a weather show,
With clouds and winds, it likes to go.
But don't you worry, it's part of nature's plan,
Just watch and learn, like a weather fan.
Enjoy the poetry (perhaps). As for the MJO: this week it may encourage
activity between the Coral Sea and Vanuatu.
TROPICS
HAIKU tracked back onto Taiwan. SAOLA skirted Hong Kong. These systems were
followed by clouds that brought the heaviest rain in over 140 years to Hong
Kong. JOVA is fading between Hawaii and Mexico; LEE and MARGOT are in the
Atlantic.
WEATHER ZONES
The South Pacific Convergence zone is expected to stretch from Solomons to
Samoa. A build-up of convection in the Coral Sea is expected to become
squally around Vanuatu on Thursday and then travel SE and deepen into a low
1 south of Fiji/Tonga in next few days. Timing may change. Avoid.
Passing troughs over and to the southeast of Southern Cooks.
HIGHS and LOWS: a steady eastwards progression this week
HIGH H1 east of Chatham Islands is travelling slowly ENE from 40S to 35S.
The trough in the south Tasman Sea is expected to cross NZ on Tuesday and
another on Thursday /Friday.
Then High H2 is expected to cross central Tasman Sea on Thu/Fri and northern
NZ over the weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 10 Sep 2023
The MJO
The MJO or Madden Julian Oscillation is the name for a bust of convection in
the tropics that travels eastwards around the equator from Indian Ocean to
Pacific Ocean. Its passage over any one place takes around a week and the
full journey from Indian to Pacific takes around 4 to 6 weeks. It's boost of
extra energy is associated with triggering tropical cyclones. Therefore, it
provides a forecasting tool.
The data shows an MJO over the Coral Sea during the coming week.
But the data description is rather complicated and can be off-putting to
non-meteorologists:
One of my regular readers added this to his blog at
https://twoatsea.com/mjo-who/
>>>>>>>>>>>>>>>>>>>
I was trying learn more about the MJO as it's coming to visit us in
Indonesia this week. I went to NOAA's website about the MJO and immediately
stumbled into this very confusing paragraph.
Forecast of MJO associated anomalous OLR for the next 15 days from the
ensemble mean GFS based on forecasts of RMM1 and RMM2. Blue (yellow/red)
shades show negative (positive) OLR anomalies and enhanced (suppressed)
convection. Forecasts do not include direct contributions from other climate
modes such as ENSO, monsoons, etc. - only the MJO.
I'm positive (negative) that I don't (do) understand, so I asked ChatGPT the
following:
I don't understand this paragraph. Can you explain it to me like I'm 5?
And Chat came to my rescue:
Of course! Let's break it down:
Imagine the Earth has a big weather "dance" going on. This dance has
different moves or patterns that change the weather. One of these dance
moves is called the MJO.
Now, scientists have a special tool (like a magic crystal ball) called the
GFS. This tool tries to guess what the MJO dance move will look like in the
next 15 days. But it's not just one guess; they make many guesses and then
take an average, which they call the "ensemble mean."
To understand the dance move better, they look at two things: RMM1 and RMM2.
Think of these as two special clues that help them guess the MJO dance move.
Now, for the colors:
Blue means there will be more clouds and rain (they call this "enhanced
convection").
Yellow or red means there will be fewer clouds and less rain (they call this
"suppressed convection").
Lastly, even though there are many other dance moves (like ENSO or monsoons)
that can change the weather, this guess is only about the MJO dance move.
They're not looking at the other moves right now.
So, in simple words, scientists are using a tool to guess how a specific
weather pattern (MJO) will change the clouds and rain in the next 15 days.
Blue means more rain, and yellow/red means less rain. And they're only
focusing on this one pattern, not the others.
-Rich
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Inspired by the idea of using Chat GPT to rewrite the MJO description I
asked it to turn its answer into a sonnet:
MJO, a rhythmic dance in the sky,
Like music playing, way up high.
It's like a big wave, moving through the air,
Bringing changes, everywhere it dares.
Imagine clouds, like fluffy cotton candy,
They gather and move, just like a trolley.
MJO makes them dance and sway,
Sometimes it brings rain, other times a sunny day.
It travels along the equator and the tropics,
From the Indian Ocean to the Western Pacific.
It's a weather pattern, you see,
That affects the world, including you and me.
So, MJO is like a weather show,
With clouds and winds, it likes to go.
But don't you worry, it's part of nature's plan,
Just watch and learn, like a weather fan.
Enjoy the poetry (perhaps). As for the MJO: this week it may encourage
activity between the Coral Sea and Vanuatu.
TROPICS
HAIKU tracked back onto Taiwan. SAOLA skirted Hong Kong. These systems were
followed by clouds that brought the heaviest rain in over 140 years to Hong
Kong. JOVA is fading between Hawaii and Mexico; LEE and MARGOT are in the
Atlantic.
WEATHER ZONES
The South Pacific Convergence zone is expected to stretch from Solomons to
Samoa. A build-up of convection in the Coral Sea is expected to become
squally around Vanuatu on Thursday and then travel SE and deepen into a low
1 south of Fiji/Tonga in next few days. Timing may change. Avoid.
Passing troughs over and to the southeast of Southern Cooks.
HIGHS and LOWS: a steady eastwards progression this week
HIGH H1 east of Chatham Islands is travelling slowly ENE from 40S to 35S.
The trough in the south Tasman Sea is expected to cross NZ on Tuesday and
another on Thursday /Friday.
Then High H2 is expected to cross central Tasman Sea on Thu/Fri and northern
NZ over the weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
03 September 2023
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Bob Blog 3 Sep
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 3 Sep 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/XOKGeaFSW3k
August shows several bursts from the Southern Ocean onto New Zealand,
showing that El Nino-type weather patterns are now occurring. Sometimes lows
lingered over northern NZ due to blocking Highs south of Tahiti. This is a
continuation of the dominate pattern in July. Here is an example of the
August pattern (8 August
Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml
Sea temperature anomalies are much the same as they were last month. Even
the El Nino warm patch is much the same. After the warmest July on the
global record, August is still record- breaking but not quite as intense.
Average isobars for past month (below)
Subtropical ridges have relaxed. The Asian monsoon is travelling east as per
normal. The trough area around New Zealand has faded.
Pressure anomalies for past month (below)
Higher than normal over Australia and NZ, and lower than normal over SE
Pacific and South America. Not much change in the Northern Hemisphere but
lower than normal pressure in the monsoon over easter Asia.
Zooming into the NZ area
Relaxing of the trough around NZ. A subtle southward shift in the
subtropical ridge. South-westerly isobars now cover NZ.
TROPICS
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Samoa. There is also a trough /convergence zone
mainly lingering over Austral Islands.
Tahiti to Tonga? Good winds for this voyage this week, but maybe some 3m
swells around Tahiti.
HIGHS and LOWS
HIGH H1 near Chatham Islands east of NZ is a blocking High and expected to
travel slowly NE/
Low L1 is a blocked Low and is being directed off to the south and
weakening. By end of the week, it is expected to be replaced by a trough
from Tasmania forming a new Low that is expected to cross the South Island
late in the week, then another over all of NZ early next week.
Tropics to NZ: look Ok this week, but avoid arrival on Mon/Tue 11/12
September
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 3 Sep 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/XOKGeaFSW3k
August shows several bursts from the Southern Ocean onto New Zealand,
showing that El Nino-type weather patterns are now occurring. Sometimes lows
lingered over northern NZ due to blocking Highs south of Tahiti. This is a
continuation of the dominate pattern in July. Here is an example of the
August pattern (8 August
Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml
Sea temperature anomalies are much the same as they were last month. Even
the El Nino warm patch is much the same. After the warmest July on the
global record, August is still record- breaking but not quite as intense.
Average isobars for past month (below)
Subtropical ridges have relaxed. The Asian monsoon is travelling east as per
normal. The trough area around New Zealand has faded.
Pressure anomalies for past month (below)
Higher than normal over Australia and NZ, and lower than normal over SE
Pacific and South America. Not much change in the Northern Hemisphere but
lower than normal pressure in the monsoon over easter Asia.
Zooming into the NZ area
Relaxing of the trough around NZ. A subtle southward shift in the
subtropical ridge. South-westerly isobars now cover NZ.
TROPICS
The South Pacific Convergence zone is expected to stay north from Solomons
to northern Vanuatu to Samoa. There is also a trough /convergence zone
mainly lingering over Austral Islands.
Tahiti to Tonga? Good winds for this voyage this week, but maybe some 3m
swells around Tahiti.
HIGHS and LOWS
HIGH H1 near Chatham Islands east of NZ is a blocking High and expected to
travel slowly NE/
Low L1 is a blocked Low and is being directed off to the south and
weakening. By end of the week, it is expected to be replaced by a trough
from Tasmania forming a new Low that is expected to cross the South Island
late in the week, then another over all of NZ early next week.
Tropics to NZ: look Ok this week, but avoid arrival on Mon/Tue 11/12
September
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
27 August 2023
Bob Blog 27 Aug
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 27 August 2023
A BLUE PERIGIAN MOON
The full moon on Thursday 31 August is the second full moon this month.
Many think the second full moon in a calendar month is called a 'blue'
moon,
perhaps because that is the colour it was given in some calendar.
But further research, such as this article
skyandtelescope.org/observing/once-in-a-blue-moon/
reveals that the origin is obscure.
This full moon is also a SUPERMOON coinciding with the monthly perigee.
It will be ~360.000km from earth and it only gets this close around three
times per year.
Of course, a closer moon means more extreme tides (both low and high).
Also, there is a lag between the perigee and the largest "king tide" of few
days.
tides.niwa.co.nz shows the tide heights plus and minus a few weeks around
this full moon for Opua in NZ (a reasonably well-behaved tidal spot with a
range ~2m) and from Karori rock near Cook strait and near a tide nodal point
(Amphidromic point) with a tide range of less than a metre (see illustrated
edition).
In its State of the Climate in the South-West Pacific 2022 report, the World
Meteorological Organization (WMO) said water levels were rising about 4 mm
per year in some South Pacific areas, slightly above the global mean rate,
so those sailing around the South Pacific should be aware of the King tides
this coming weekend
TROPICS
It has been a busy week for cyclones and tropical depressions.
HILLARY swamped LA and SanDiego. HAROLD brought rain to southern Texas.
FRANKLIN brought heavy rain to Hispaniola.
EMILY and GERT had brief lives in the central North Atlantic. SAOLA visited
Philippines and DAMRAY affected Japan.
WEATHER ZONES
The South Pacific Convergence zone is expected to intensify this week
between Solomons and Vanuatu and drift south and form a LOW L1 near New
Caledonia by mid-week Wednesday. Fresh trade winds over Tonga and the Cooks.
A lingering lull about French Polynesia this week
HIGHS and LOWS
Low L1 near New Caledonia by mid-week expected to deepen and travel SE
towards northern NZ.
HIGH H1 1031 in South Tasman Sea travelling east across NZ mid-week. Avoid
squash zone between H1 and L1.
Low and trough L3 expected to travel NE from Southern Ocean to south Tasman
Sea by end of week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt +64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 27 August 2023
A BLUE PERIGIAN MOON
The full moon on Thursday 31 August is the second full moon this month.
Many think the second full moon in a calendar month is called a 'blue'
moon,
perhaps because that is the colour it was given in some calendar.
But further research, such as this article
skyandtelescope.org/observing/once-in-a-blue-moon/
reveals that the origin is obscure.
This full moon is also a SUPERMOON coinciding with the monthly perigee.
It will be ~360.000km from earth and it only gets this close around three
times per year.
Of course, a closer moon means more extreme tides (both low and high).
Also, there is a lag between the perigee and the largest "king tide" of few
days.
tides.niwa.co.nz shows the tide heights plus and minus a few weeks around
this full moon for Opua in NZ (a reasonably well-behaved tidal spot with a
range ~2m) and from Karori rock near Cook strait and near a tide nodal point
(Amphidromic point) with a tide range of less than a metre (see illustrated
edition).
In its State of the Climate in the South-West Pacific 2022 report, the World
Meteorological Organization (WMO) said water levels were rising about 4 mm
per year in some South Pacific areas, slightly above the global mean rate,
so those sailing around the South Pacific should be aware of the King tides
this coming weekend
TROPICS
It has been a busy week for cyclones and tropical depressions.
HILLARY swamped LA and SanDiego. HAROLD brought rain to southern Texas.
FRANKLIN brought heavy rain to Hispaniola.
EMILY and GERT had brief lives in the central North Atlantic. SAOLA visited
Philippines and DAMRAY affected Japan.
WEATHER ZONES
The South Pacific Convergence zone is expected to intensify this week
between Solomons and Vanuatu and drift south and form a LOW L1 near New
Caledonia by mid-week Wednesday. Fresh trade winds over Tonga and the Cooks.
A lingering lull about French Polynesia this week
HIGHS and LOWS
Low L1 near New Caledonia by mid-week expected to deepen and travel SE
towards northern NZ.
HIGH H1 1031 in South Tasman Sea travelling east across NZ mid-week. Avoid
squash zone between H1 and L1.
Low and trough L3 expected to travel NE from Southern Ocean to south Tasman
Sea by end of week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt +64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
20 August 2023
Bob Blog
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 20August 2023
How big is the HOLE this spring?
During the dark of winter chemicals build in the air above Antarctica. When
sunlight returns at the end of winter and start of spring, between August
and October, this triggers chemical reactions which delete the Ozone
concentration in the Stratosphere. During the second half of last century
CFC gases were used in refrigeration and as a spray can expellant and vented
into the atmosphere triggering depletion of ozone over Antarctica every
spring-a phenomenon called the OZONE HOLE.
Scientific study of this depletion in the 1960 to 1980s lead to WMO
declaring the Montreal protocol in 1987 to phase out CFC. This is a rare
treaty that achieved universal ratification. It has been considered as a
success for the UN, and a sign that humans can mitigate planetary pollution.
However, this month observations show an earlier than normal depletion in
Antarctic ozone. If this continues, we may have as big a hole as in the bad
years around 2000. This time it isn't CFC to blame. The theory is that it
may be due to extra water vapour and some other gases from the Hunga -Tonga
/Hunga Ha'apai Volcano in January 2022. The blast produced a sonic boom that
travelled several times around the planet and a plume that rose 58km into
the Mesosphere and threw "unprecedented" amounts of water vapor into the
stratosphere.
In August 2022, a NASA report stated, ".as detected by NASA's Microwave Limb
Sounder.. The excess water vapor injected (into the stratosphere) by the
Tonga volcano... could remain in the stratosphere for several years... would
have a small temporary warming effect.... would not be enough to noticeably
exacerbate climate change effects."
Maybe this water vapor has found time during winter to build in the
Antarctic. In the stratosphere it acts as a "greenhouse" gas and reflects
infrared radiation in all directions, with that directed downwards warming
the surface. Sunlight converts some of it into hydrogen oxide molecules and
these destroy ozone.
Ozone absorbs UV and uses this to warm the stratosphere. The main effect of
an ozone hole is an increase in UV reaching the earth's surface and
consequential sunburn. Less ozone also means less warming of the
stratosphere from sunlight. A cooler stratosphere strengthens the polar
vortex, affecting the surface weather.
A good parameter to check out the polar vortex is SAM (or its proxy AAO)
At present it is negative, and that is consistent with a weak polar vortex.
So we shall watch the trends and see what happens with the Ozone hole over
the next few months.
TROPICS
It has been a busy week for cyclones and tropical depressions.
LAN visited Honshu Island in Japan. GREG and FERNANDA travelled west across
the North Pacific. HILLARY is threatening southern California and there are
two, maybe three tropical depressions in the Atlantic.
WEATHER ZONES
The South Pacific Convergence zone is expected to have a quiet week across
the northern Coral Sea to Samoa. A showery trough lingers well south of
Society Islands. Another is expected to form over the Fiji area by mid-week
and then go east fand fade over Southern Cooks.
Apart from these troughs it looks to be a good week for sailing from Tahiti
to Tonga.
HIGHS and LOWS
Low L1 is expected to deepen to around 985 near Chathams on Monday and then
spin clockwise and then go southeast, feeding cold showery weather on
eastern NZ.
HIGH H1 should form in the north Tasman Se by mid-week then fade.
Another Low L2 from the south Tasman Sea is expected to bring unsettled
weather to NZ this weekend.
A good week for getting westwards across the Coral Sea and North Tasman Sea
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt +64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 20August 2023
How big is the HOLE this spring?
During the dark of winter chemicals build in the air above Antarctica. When
sunlight returns at the end of winter and start of spring, between August
and October, this triggers chemical reactions which delete the Ozone
concentration in the Stratosphere. During the second half of last century
CFC gases were used in refrigeration and as a spray can expellant and vented
into the atmosphere triggering depletion of ozone over Antarctica every
spring-a phenomenon called the OZONE HOLE.
Scientific study of this depletion in the 1960 to 1980s lead to WMO
declaring the Montreal protocol in 1987 to phase out CFC. This is a rare
treaty that achieved universal ratification. It has been considered as a
success for the UN, and a sign that humans can mitigate planetary pollution.
However, this month observations show an earlier than normal depletion in
Antarctic ozone. If this continues, we may have as big a hole as in the bad
years around 2000. This time it isn't CFC to blame. The theory is that it
may be due to extra water vapour and some other gases from the Hunga -Tonga
/Hunga Ha'apai Volcano in January 2022. The blast produced a sonic boom that
travelled several times around the planet and a plume that rose 58km into
the Mesosphere and threw "unprecedented" amounts of water vapor into the
stratosphere.
In August 2022, a NASA report stated, ".as detected by NASA's Microwave Limb
Sounder.. The excess water vapor injected (into the stratosphere) by the
Tonga volcano... could remain in the stratosphere for several years... would
have a small temporary warming effect.... would not be enough to noticeably
exacerbate climate change effects."
Maybe this water vapor has found time during winter to build in the
Antarctic. In the stratosphere it acts as a "greenhouse" gas and reflects
infrared radiation in all directions, with that directed downwards warming
the surface. Sunlight converts some of it into hydrogen oxide molecules and
these destroy ozone.
Ozone absorbs UV and uses this to warm the stratosphere. The main effect of
an ozone hole is an increase in UV reaching the earth's surface and
consequential sunburn. Less ozone also means less warming of the
stratosphere from sunlight. A cooler stratosphere strengthens the polar
vortex, affecting the surface weather.
A good parameter to check out the polar vortex is SAM (or its proxy AAO)
At present it is negative, and that is consistent with a weak polar vortex.
So we shall watch the trends and see what happens with the Ozone hole over
the next few months.
TROPICS
It has been a busy week for cyclones and tropical depressions.
LAN visited Honshu Island in Japan. GREG and FERNANDA travelled west across
the North Pacific. HILLARY is threatening southern California and there are
two, maybe three tropical depressions in the Atlantic.
WEATHER ZONES
The South Pacific Convergence zone is expected to have a quiet week across
the northern Coral Sea to Samoa. A showery trough lingers well south of
Society Islands. Another is expected to form over the Fiji area by mid-week
and then go east fand fade over Southern Cooks.
Apart from these troughs it looks to be a good week for sailing from Tahiti
to Tonga.
HIGHS and LOWS
Low L1 is expected to deepen to around 985 near Chathams on Monday and then
spin clockwise and then go southeast, feeding cold showery weather on
eastern NZ.
HIGH H1 should form in the north Tasman Se by mid-week then fade.
Another Low L2 from the south Tasman Sea is expected to bring unsettled
weather to NZ this weekend.
A good week for getting westwards across the Coral Sea and North Tasman Sea
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt +64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
13 August 2023
Bob Blog
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 13 August 2023
Public Holidays
Sailors crossing the South Pacific are juggling their travel taking into
account factors such as the weather, and time out for tropical relaxation,
maintenance, and provisioning, plus the impending end of the cruising season
at end of October. 1 November is the nominal start of the cyclone season.
One factor that isn't usually taken int account, but can prove to be an
embarrassment or even a problem for newbies is the rather peculiar variation
in public holidays across the South Pacific
For example, tomorrow is a public holiday in Samoa for Father's Day, and
Tuesday is a public holiday in NEW CALEDONIA, FRENCH POLYNESIA and VANATU to
commemorate the Assumption of Mary. (Mary's assumption is also the patron of
Aotearoa /New Zealand, but not a public holiday there).
So, to help you plan voyaging between now and the end of the year here are
the public holidays across the South Pacific, from east to west and from
north to south
French Polynesia:
August 15 Assumption Day
November 1 All Saints' Day
November 11 Armistice Day
December 25 Christmas Day
Cooks :
26 October Gospel Day
25 December Christmas Day
26 December Boxing Day
Niue:
19 October Constitution Day
30 October Fourth Monday in October Peniamina Gospel Day
25 December Christmas Day
December Boxing Day
American Samoa
30 Nov (4th Thursday) Thanksgiving Day
25 December Christmas
26 December Family Day
Tonga
18 Sep Crown Prince's Birthday
6 Nov Tonga Day
4 Dec King Tupou I Day
25 Dec Christmas Day
26 Dec Boxing Day
Samoa
14 Aug Father's Day
9 Oct Lotu a Tamaiti (Day after white Sunday)
25 Dec Christmas Day
26 December Boxing Day
Fiji
7 September Constitution Day
Evg 26sep to evg 27sep Mawlid
10 October Fiji Day
13 November Diwali
25 December Christmas Day
26 December Boxing Day
New Zealand
23 October Labour Day
25 December Christmas Day
26 December Boxing day
Vanuatu
15 August Assumption Day
5 October Constitution day
29 November National Unity Day
25 December Christmas Day
26 December Family Day
New Caledonia
15 August Assumption day
24 September New Caledonia Day
1 November All Saint's Day
11 November Armistice Day
25 December Christmas Day
Australia observe Christmas and Boxing Days
Norfolk Island adds the following
9 Oct Norfolk Island Agricultural Show Day
29 Nov Thanksgiving Day (30 Nov in USA)
TROPICS
DORA stayed south of Hawaii but, in cahoots with a large HIGH at 30N,
brought a squash zone of enhance trade winds to Hawaii that fanned some
wildfires, bringing widespread death and destruction.
FERNANDA is now off the west of Mexico, and LAN is heading for Tokyo.
WEATHER ZONES
The South Pacific Convergence zone is expected to have a quiet week across
the Coral Sea to north of Fiji. A showery trough is expected to form over
the Fiji area by mid-week and then go southeast forming a new Low near 30S
south of southern Cooks by end of the week. Apart from this trough it looks
to be a good week for sailing from Tahiti to Tonga.
HIGHS and LOWS
There is a strong subtropical ridge along about 30 to 35S
HIGH H1 to north of NZ tonight is expected to travel steadily east to
southeast east of NZ.
Low L1 is somewhat blocked by a ring of high pressure all around and should
drift slowly to between Wallington and Chathams by mid-week, and then off to
the southeast.
HIGH H2 is expected to spread into western Tasman Sea by mid-week and then
travel northeast across NZ on Thursday and Friday, followed by another
trough from Saturday.
Nothing intense enough to consider avoiding this week. However, L1 over NZ
until Wednesday is bringing southerlies and cold rain., with often strong
winds around Cook Strait.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 13 August 2023
Public Holidays
Sailors crossing the South Pacific are juggling their travel taking into
account factors such as the weather, and time out for tropical relaxation,
maintenance, and provisioning, plus the impending end of the cruising season
at end of October. 1 November is the nominal start of the cyclone season.
One factor that isn't usually taken int account, but can prove to be an
embarrassment or even a problem for newbies is the rather peculiar variation
in public holidays across the South Pacific
For example, tomorrow is a public holiday in Samoa for Father's Day, and
Tuesday is a public holiday in NEW CALEDONIA, FRENCH POLYNESIA and VANATU to
commemorate the Assumption of Mary. (Mary's assumption is also the patron of
Aotearoa /New Zealand, but not a public holiday there).
So, to help you plan voyaging between now and the end of the year here are
the public holidays across the South Pacific, from east to west and from
north to south
French Polynesia:
August 15 Assumption Day
November 1 All Saints' Day
November 11 Armistice Day
December 25 Christmas Day
Cooks :
26 October Gospel Day
25 December Christmas Day
26 December Boxing Day
Niue:
19 October Constitution Day
30 October Fourth Monday in October Peniamina Gospel Day
25 December Christmas Day
December Boxing Day
American Samoa
30 Nov (4th Thursday) Thanksgiving Day
25 December Christmas
26 December Family Day
Tonga
18 Sep Crown Prince's Birthday
6 Nov Tonga Day
4 Dec King Tupou I Day
25 Dec Christmas Day
26 Dec Boxing Day
Samoa
14 Aug Father's Day
9 Oct Lotu a Tamaiti (Day after white Sunday)
25 Dec Christmas Day
26 December Boxing Day
Fiji
7 September Constitution Day
Evg 26sep to evg 27sep Mawlid
10 October Fiji Day
13 November Diwali
25 December Christmas Day
26 December Boxing Day
New Zealand
23 October Labour Day
25 December Christmas Day
26 December Boxing day
Vanuatu
15 August Assumption Day
5 October Constitution day
29 November National Unity Day
25 December Christmas Day
26 December Family Day
New Caledonia
15 August Assumption day
24 September New Caledonia Day
1 November All Saint's Day
11 November Armistice Day
25 December Christmas Day
Australia observe Christmas and Boxing Days
Norfolk Island adds the following
9 Oct Norfolk Island Agricultural Show Day
29 Nov Thanksgiving Day (30 Nov in USA)
TROPICS
DORA stayed south of Hawaii but, in cahoots with a large HIGH at 30N,
brought a squash zone of enhance trade winds to Hawaii that fanned some
wildfires, bringing widespread death and destruction.
FERNANDA is now off the west of Mexico, and LAN is heading for Tokyo.
WEATHER ZONES
The South Pacific Convergence zone is expected to have a quiet week across
the Coral Sea to north of Fiji. A showery trough is expected to form over
the Fiji area by mid-week and then go southeast forming a new Low near 30S
south of southern Cooks by end of the week. Apart from this trough it looks
to be a good week for sailing from Tahiti to Tonga.
HIGHS and LOWS
There is a strong subtropical ridge along about 30 to 35S
HIGH H1 to north of NZ tonight is expected to travel steadily east to
southeast east of NZ.
Low L1 is somewhat blocked by a ring of high pressure all around and should
drift slowly to between Wallington and Chathams by mid-week, and then off to
the southeast.
HIGH H2 is expected to spread into western Tasman Sea by mid-week and then
travel northeast across NZ on Thursday and Friday, followed by another
trough from Saturday.
Nothing intense enough to consider avoiding this week. However, L1 over NZ
until Wednesday is bringing southerlies and cold rain., with often strong
winds around Cook Strait.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
06 August 2023
Bob Blog 6 Aug
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 06 August 2023
SPCZ + Jetstream = wonky weather.
SPCZ, the south Pacific Convergence Zone is well known to Pacifica peoples.
It is where the easterly winds on the north side of the Easter Island High
bumps into the SE winds found on the north side of the Highs that migrate
across the Tasman Sea,
In previous blogs I've talked about how it has "moods" depending on things
like long term influences such as El Nino/La Nania, and the annual cycle,
and shorter cycles such as the MJO.
The recent weather over Vanuatu has been so wonky it prompted the request to
"explain the (for us) strange weather pattern that we experience now around
Vanuatu. It is not a ' normal' low, but what is it then?"
The surface map last Thursday shows a large 1039 High in the central Tasman
Sea and a zone of enhanced SE winds over Vanuatu. I call this a SQUASH ZONE.
The well-formed upper trough with Jetstreams is directly above the squash
zone and over Vanuatu. This helps cause strong upward motion leading to
squally weather. This upper trough has now deformed and Vanuatu weather is
now relaxing, The SPCZ stays lingering over northern Vanuatu much as it
usually does. It was the upper trough/Jetstream that produced the wonky
weather.
TROPICS
Former super typhoon DOKSURI brought the heaviest rain to east Chimba since
records began 140 years ago. Super Typhoon KHANUN followed and skirted
southern Japan. Cyclone and is now heading for Korea. DORA is travelling
west along 12N south of Hawaii, and EUGENE is travelling NW parallel to Baja
California coast. There is now high potential for development in the
Atlantic. As the old saying goes "July, stand by. August, a must".
WEATHER ZONES
The South Pacific Convergence zone is expected to have a quiet week across
the Coral Sea to north of Fiji. From the recent wonky weather over Vanuatu a
LOW L1 is forming near Fiji and expected to track to the SE and deepen. A
convergence zone is expected to linger between Northern Tonga and Austral
Island. It has some passing troughs, but these are mediocre, and weather
seems Ok for sailing from Tahiti to Tonga afterL1 has moved off. Northern
route avoids most of the convergence zone.
HIGHS and LOWS
There is a strong subtropical ridge along about 32S
Low to NE of Chathams Islands tonight is moving quickly off to the east and
High H1 should form east of NZ by mid-week.
Low L2 over southern NZ tonight is expected to travel NE and linger near
Chathams until Thursday, bringing a cold south/southwest flow to NZ.
After a ridge over NZ on Friday/Saturday the next trough is expected to
deepen into a slow-moving low over north Island early next week. Avoid.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 06 August 2023
SPCZ + Jetstream = wonky weather.
SPCZ, the south Pacific Convergence Zone is well known to Pacifica peoples.
It is where the easterly winds on the north side of the Easter Island High
bumps into the SE winds found on the north side of the Highs that migrate
across the Tasman Sea,
In previous blogs I've talked about how it has "moods" depending on things
like long term influences such as El Nino/La Nania, and the annual cycle,
and shorter cycles such as the MJO.
The recent weather over Vanuatu has been so wonky it prompted the request to
"explain the (for us) strange weather pattern that we experience now around
Vanuatu. It is not a ' normal' low, but what is it then?"
The surface map last Thursday shows a large 1039 High in the central Tasman
Sea and a zone of enhanced SE winds over Vanuatu. I call this a SQUASH ZONE.
The well-formed upper trough with Jetstreams is directly above the squash
zone and over Vanuatu. This helps cause strong upward motion leading to
squally weather. This upper trough has now deformed and Vanuatu weather is
now relaxing, The SPCZ stays lingering over northern Vanuatu much as it
usually does. It was the upper trough/Jetstream that produced the wonky
weather.
TROPICS
Former super typhoon DOKSURI brought the heaviest rain to east Chimba since
records began 140 years ago. Super Typhoon KHANUN followed and skirted
southern Japan. Cyclone and is now heading for Korea. DORA is travelling
west along 12N south of Hawaii, and EUGENE is travelling NW parallel to Baja
California coast. There is now high potential for development in the
Atlantic. As the old saying goes "July, stand by. August, a must".
WEATHER ZONES
The South Pacific Convergence zone is expected to have a quiet week across
the Coral Sea to north of Fiji. From the recent wonky weather over Vanuatu a
LOW L1 is forming near Fiji and expected to track to the SE and deepen. A
convergence zone is expected to linger between Northern Tonga and Austral
Island. It has some passing troughs, but these are mediocre, and weather
seems Ok for sailing from Tahiti to Tonga afterL1 has moved off. Northern
route avoids most of the convergence zone.
HIGHS and LOWS
There is a strong subtropical ridge along about 32S
Low to NE of Chathams Islands tonight is moving quickly off to the east and
High H1 should form east of NZ by mid-week.
Low L2 over southern NZ tonight is expected to travel NE and linger near
Chathams until Thursday, bringing a cold south/southwest flow to NZ.
After a ridge over NZ on Friday/Saturday the next trough is expected to
deepen into a slow-moving low over north Island early next week. Avoid.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
30 July 2023
Bob Blog 30 July
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 30 July 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/wDmVQCMfqxU
July shows plenty of Southwest bursts from the Southern Ocean onto New
Zealand, showing that El Nino-type weather patterns are now occurring.
Sometimes lows lingered over northern NZ due to blocking Highs south of
Tahiti. This was a continuation of the dominate pattern in June. Here is an
example of the July pattern (9 July)
Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml
Sea temperature anomalies are warmer in the northern Hemisphere than last
month. in fact the northern Hemisphere air temperature in July 2023 broke
many heat records. Not much change with the equatorial warm patch in the
eastern Pacific the cause of the El Nino) or in the warm spots in the
Southern Hemisphere.
Average isobars for past month (below)
From www.psl.noaa.gov/map/images/fnl/slp_30b.fnl.html
Subtropical ridges have intensified. This is typical of July. The Asian
monsoon is travelling east as per normal.
Pressure anomalies for past month (below)
Higher than normal pressure reveals a heat dome over Europe and Asia. NZ
remains a breeding ground for lows and south of Tahiti still has a lingering
high. Australia and South Africa has flipped from low to high.
Zooming into the NZ area
South-westerly isobars now cover NZ. The westerly winds have relaxed at 50
to 60S
TROPICS
Cyclone DOKSURI travelled from northern Philippines to southern Taiwan and
is now being followed by KHANUN. There are tropical depressions west of
Mexico and east of the Caribbean.
The MJO, a burst of extra energy in the tropics, is moving across Indonesia.
WEATHER ZONES
The South Pacific Convergence zone is expected to build over the Coral Sea
and Vanuatu towards Samoa. An intense convergence zone/ trough is expected
to linger from Niue area to Southern Cooks. Squally Low L3 might form north
of Fiji late in the week and move SE across Tonga followed by a burst of
over 3m long -period southerly swell.
Tahiti to Tonga? Avoid L3. Looks Ok to go to Suwarrow.
HIGHS and LOWS
Low L1 well east of NZ should continue to move off to the southeast.
Low L2 is this week's main protagonist crossing the south Tasman by
Wednesday and then going NE off the NZ east coast followed by strong cold
southerly winds and over 4m swells reaching to 30S by weekend.
High H1 stays in the mid north Tasman Sea and is expected to bring OK
weather to North Island until end of Tuesday for fast boats exiting north or
going west across northern Tasman.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 30 July 2023
A review of last month's weather
Here is a link to a YouTube clip giving an animated loop of the isobars and
streamlines in the South Pacific for the last month at youtu.be/wDmVQCMfqxU
July shows plenty of Southwest bursts from the Southern Ocean onto New
Zealand, showing that El Nino-type weather patterns are now occurring.
Sometimes lows lingered over northern NZ due to blocking Highs south of
Tahiti. This was a continuation of the dominate pattern in June. Here is an
example of the July pattern (9 July)
Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml
Sea temperature anomalies are warmer in the northern Hemisphere than last
month. in fact the northern Hemisphere air temperature in July 2023 broke
many heat records. Not much change with the equatorial warm patch in the
eastern Pacific the cause of the El Nino) or in the warm spots in the
Southern Hemisphere.
Average isobars for past month (below)
From www.psl.noaa.gov/map/images/fnl/slp_30b.fnl.html
Subtropical ridges have intensified. This is typical of July. The Asian
monsoon is travelling east as per normal.
Pressure anomalies for past month (below)
Higher than normal pressure reveals a heat dome over Europe and Asia. NZ
remains a breeding ground for lows and south of Tahiti still has a lingering
high. Australia and South Africa has flipped from low to high.
Zooming into the NZ area
South-westerly isobars now cover NZ. The westerly winds have relaxed at 50
to 60S
TROPICS
Cyclone DOKSURI travelled from northern Philippines to southern Taiwan and
is now being followed by KHANUN. There are tropical depressions west of
Mexico and east of the Caribbean.
The MJO, a burst of extra energy in the tropics, is moving across Indonesia.
WEATHER ZONES
The South Pacific Convergence zone is expected to build over the Coral Sea
and Vanuatu towards Samoa. An intense convergence zone/ trough is expected
to linger from Niue area to Southern Cooks. Squally Low L3 might form north
of Fiji late in the week and move SE across Tonga followed by a burst of
over 3m long -period southerly swell.
Tahiti to Tonga? Avoid L3. Looks Ok to go to Suwarrow.
HIGHS and LOWS
Low L1 well east of NZ should continue to move off to the southeast.
Low L2 is this week's main protagonist crossing the south Tasman by
Wednesday and then going NE off the NZ east coast followed by strong cold
southerly winds and over 4m swells reaching to 30S by weekend.
High H1 stays in the mid north Tasman Sea and is expected to bring OK
weather to North Island until end of Tuesday for fast boats exiting north or
going west across northern Tasman.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
23 July 2023
Bob Blog
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 23 July 2023
Waves: Height(m) x Height (m) x period (Sec) = Power (in KW/m)
This is a simple approximation for estimating wave power.
So a 2m wave with period 7 sec has power of 28 kW/m
And a 4m wave with a period 7sec has Power 112 kW/m (four times more)
This is based on some lecture notes in a training video at
www.youtube.com/watch?v=2ODs5lxqRdw
TROPICS
TALIM uprooted trees in South China, remnants of CALVIN skirted around
southern Hawaiian Islands, DON went across the north Atlantic and DOKSURI
spun up east of Philippines.
The MJO, a burst of extra energy in the tropics, is on the move and expected
to visit the Indonesian longitudes in the next week or so and reach west
Pacific early August.
WEATHER ZONES
The South Pacific Convergence zone is expected to extend from Coral Sea to
Vanuatu and Samoa.
Low L1 near Niue is moving off to the southeast and associated convergence
zone is expected to travel east and cross southern cooks late this week.
HIGH H1 well east of NZ and at 45S is quasi -stationary and drifting east,
blocking the lows on its western shoulder.
Low L2 near Chatham Islands tonight is being steered southwards around H1,
maintaining a cold snap and a southerly flow over New Zealand.
In this southerly flow a second cold burst crosses NZ on Wed and then turns
into low L3 off North Island that curves to the SE. This is followed by a
third cold burst and then low over northern NZ next weekend.
After that HIGH H2 might finally have a chance to cross the northern Tasman
Sea early next week.
The southerly flow over NZ this week is likely to reach as far as Minerva,
and the swells may be over 3m at times.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Text archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 23 July 2023
Waves: Height(m) x Height (m) x period (Sec) = Power (in KW/m)
This is a simple approximation for estimating wave power.
So a 2m wave with period 7 sec has power of 28 kW/m
And a 4m wave with a period 7sec has Power 112 kW/m (four times more)
This is based on some lecture notes in a training video at
www.youtube.com/watch?v=2ODs5lxqRdw
TROPICS
TALIM uprooted trees in South China, remnants of CALVIN skirted around
southern Hawaiian Islands, DON went across the north Atlantic and DOKSURI
spun up east of Philippines.
The MJO, a burst of extra energy in the tropics, is on the move and expected
to visit the Indonesian longitudes in the next week or so and reach west
Pacific early August.
WEATHER ZONES
The South Pacific Convergence zone is expected to extend from Coral Sea to
Vanuatu and Samoa.
Low L1 near Niue is moving off to the southeast and associated convergence
zone is expected to travel east and cross southern cooks late this week.
HIGH H1 well east of NZ and at 45S is quasi -stationary and drifting east,
blocking the lows on its western shoulder.
Low L2 near Chatham Islands tonight is being steered southwards around H1,
maintaining a cold snap and a southerly flow over New Zealand.
In this southerly flow a second cold burst crosses NZ on Wed and then turns
into low L3 off North Island that curves to the SE. This is followed by a
third cold burst and then low over northern NZ next weekend.
After that HIGH H2 might finally have a chance to cross the northern Tasman
Sea early next week.
The southerly flow over NZ this week is likely to reach as far as Minerva,
and the swells may be over 3m at times.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to
see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe
at bottom).
Text archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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