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 25 July 2021
Regarding last week's blog, with its checklist for handling a squall, it has
been suggested that the mnemonic for remembering it be replaced with the
word PRICK (rather than APRICOT), dropping the A (Anticipate) and O (Over),
and replacing the T for Thunder with K. Rather rude but more memorable.
Also, this week I would like to share with you a link to a COMPRENDIUM OF
WEATHER INFORMATION FOR FRENCH POLYNESIA
(svsoggypaws.com/files/French%20Polynesia%20Weather%20Compendium.pdf) as
prepared by David Vogel and available with a host of other information at
svsoggypaws.com/files/. This is a must read for yachts visiting French
Polynesia and useful for those planning to get from there westwards across
the South Pacific.
TROPICS
The latest cyclone activity report is at tropic.ssec.wisc.edu and Tropical
Cyclone Potential is from www.ssd.noaa.gov/PS/TROP/TCFP/index.html
In-Fa is making landfall onto China. Cyclone NEPARTAK is heading towards
Japan, and expected to weaken (a little) on Tuesday. So, the outlook is for
wet and windy conditions mid-week for the Tokyo Olympics.
WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ is expected to be about average stretching from Solomon Islands to
Fiji/Tonga, and a convergence zone s expected near Samoa occasionally over
Southern Cooks and Tahiti area.
HIGHS and LOWS
1 Active trough is crossing NZ tonight and on Monday followed by squally
west to southwest flow until Tuesday. Avoid.
2 LOW traveling east along 30S south of Southern Cooks early this week
bringing light winds to French Polynesia FP.
3 HIGH 1020+in Northern Tasman Sea by Tuesday expected to travel east along
30S and reach south of FP by end of the week. Good trade winds with this
High.
4 Active trough in Tasman Sea by Thursday. LOW 995 expected to form in this
trough over northern NZ on local Friday and then travel east along 30S until
early next week bringing westerly winds as far north as Samoa. Good for
getting east but wait until early Aug if going west from FP.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more detail for 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 64277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
25 July 2021
18 July 2021
Bob Blog 18 July 2021
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 18 July 2021
I thought I'd share with you today my Squall checklist.
Note that I'm basically a landlubber and have only sailed through two
squalls, both near the shore.
APRICOT (mnemonic for remembering the checklist. A-P-R-I-C-O-T
And if you have any suggestions please reply with a comment.
1) ANTICIPATE: Go on squall watch when near a convergence zone. At start of
your shift set your barometer (or note pressure reading). Scan: Get into
routine of watching clouds on the horizon into the wind, into the lee, then
left and right of the wind--- occasionally check for a drop in the
barometer.
2) PUT ON/ PUT AWAY. When you see a darkening cloud heading towards you, or
feel the boat creak differently, put on: check that lifejackets/harnesses/
foul weather gear is on hand; put away- clear the decks of loose gear, close
ports and hatches.
3) REDUCE: reduce sail. At first sign of wind on water, reef main. At first
gust, trim jib.
4) IDLE? Shall we idle/park the boat? Turn engine off if under power.
Consider idea of heaving-to if at sea or anchoring if in the shallows.
5) COMPASS: Hazards: If near land or a reef, take a bearing to nearest
hazard before visibility reduces/wind changes. In mid-latitudes in southern
hemisphere wind will probably BACK (go left) during the squall.
6) OVER: Its normally all OVER in 20 to 40 minutes then, Oh-O, there is a
lull of 20-40 minutes with little wind to power the sails and chaotic steep
waves, an unpleasant motion.
7) THUNDER: Time to turn off the electrics. Lightning is static electricity
and takes the line of least resistance-along the rigging, Safest place is
amidships.
If boat broaches (too much sail/structure caught by a gust), HOLD ON, take
your time, ease the sheets, ease the boom vang. As the boat uprights, beware
of flogging sheets
TROPICS
The latest cyclone activity report is at tropic.ssec.wisc.edu and Tropical
Cyclone Potential is from www.ssd.noaa.gov/PS/TROP/TCFP/index.html
Three cyclones around at present: In-Fa is expected to visit Taiwan.
FELICIA and GUILLERMO should fade in the Northeast Pacific
WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ is expected to be about average stretching from Solomon Islands to
Fiji/Samoa, and occasionally over Southern Cooks and Tahiti area.
Two passing troughs for the South Pacific this week. The first one fades
over Tonga on local Monday/Tuesday and the second is expected to reach New
Caledonia on local Tuesday, and deepen into a low south of Tonga by local
Saturday. A good week for getting west from French Polynesia.
HIGHS and LOWS
HIGH over 1030 well south of French Polynesia is expected to travel off to
the east along 35S.
Complex TROUGH below 990 over South Island tonight is expected to travel off
to the east along 40S. This trough brought a large area of over 200mm of
rain to The Sothern Alps in NZ over past few days, producing plenty of
flooding tinyurl.com/nzfloodingjul2021, but less than the deluge in West
Germany tinyurl.com/GermanyfloodsJul2021
HIGH over 1020 over central Australia expected to bud off a ridge around
1016 that crosses North Tasman Sea on Monday and then travels east along
25/30S
Complex TROUGH is expected to reach Tasmania on Tuesday and cross NZ on
Thursday.
Another HIGH is expected to move off Australia into the Tasman Sea on
Thursday and cross NZ on Friday/Saturday.
This weather traffic makes crossing the Tasman sort of like playing Fogger.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more detail for 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 64277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 18 July 2021
I thought I'd share with you today my Squall checklist.
Note that I'm basically a landlubber and have only sailed through two
squalls, both near the shore.
APRICOT (mnemonic for remembering the checklist. A-P-R-I-C-O-T
And if you have any suggestions please reply with a comment.
1) ANTICIPATE: Go on squall watch when near a convergence zone. At start of
your shift set your barometer (or note pressure reading). Scan: Get into
routine of watching clouds on the horizon into the wind, into the lee, then
left and right of the wind--- occasionally check for a drop in the
barometer.
2) PUT ON/ PUT AWAY. When you see a darkening cloud heading towards you, or
feel the boat creak differently, put on: check that lifejackets/harnesses/
foul weather gear is on hand; put away- clear the decks of loose gear, close
ports and hatches.
3) REDUCE: reduce sail. At first sign of wind on water, reef main. At first
gust, trim jib.
4) IDLE? Shall we idle/park the boat? Turn engine off if under power.
Consider idea of heaving-to if at sea or anchoring if in the shallows.
5) COMPASS: Hazards: If near land or a reef, take a bearing to nearest
hazard before visibility reduces/wind changes. In mid-latitudes in southern
hemisphere wind will probably BACK (go left) during the squall.
6) OVER: Its normally all OVER in 20 to 40 minutes then, Oh-O, there is a
lull of 20-40 minutes with little wind to power the sails and chaotic steep
waves, an unpleasant motion.
7) THUNDER: Time to turn off the electrics. Lightning is static electricity
and takes the line of least resistance-along the rigging, Safest place is
amidships.
If boat broaches (too much sail/structure caught by a gust), HOLD ON, take
your time, ease the sheets, ease the boom vang. As the boat uprights, beware
of flogging sheets
TROPICS
The latest cyclone activity report is at tropic.ssec.wisc.edu and Tropical
Cyclone Potential is from www.ssd.noaa.gov/PS/TROP/TCFP/index.html
Three cyclones around at present: In-Fa is expected to visit Taiwan.
FELICIA and GUILLERMO should fade in the Northeast Pacific
WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ is expected to be about average stretching from Solomon Islands to
Fiji/Samoa, and occasionally over Southern Cooks and Tahiti area.
Two passing troughs for the South Pacific this week. The first one fades
over Tonga on local Monday/Tuesday and the second is expected to reach New
Caledonia on local Tuesday, and deepen into a low south of Tonga by local
Saturday. A good week for getting west from French Polynesia.
HIGHS and LOWS
HIGH over 1030 well south of French Polynesia is expected to travel off to
the east along 35S.
Complex TROUGH below 990 over South Island tonight is expected to travel off
to the east along 40S. This trough brought a large area of over 200mm of
rain to The Sothern Alps in NZ over past few days, producing plenty of
flooding tinyurl.com/nzfloodingjul2021, but less than the deluge in West
Germany tinyurl.com/GermanyfloodsJul2021
HIGH over 1020 over central Australia expected to bud off a ridge around
1016 that crosses North Tasman Sea on Monday and then travels east along
25/30S
Complex TROUGH is expected to reach Tasmania on Tuesday and cross NZ on
Thursday.
Another HIGH is expected to move off Australia into the Tasman Sea on
Thursday and cross NZ on Friday/Saturday.
This weather traffic makes crossing the Tasman sort of like playing Fogger.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more detail for 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 64277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
11 July 2021
Bob Blog 11 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 11 July 2021
In 2016 I introduced a series of blogs on the topic of "buffering" in Goggle
maps and how sometimes it shows open ocean where there are reefs. This data
saving tactic is called "Google lacunae"
Art of SV Feeling Good introduced us to OVITAL MAP which allows downloading
satellite images from various sources. Sadly, I have now been informed by
Eve of SV Auntie that Ovital Map has taken itself out of this business as it
now only uses Chinese satellites in which French Polynesia isn't covered.
Tom of Yacht Adina wrote a detailed account of navigating with satellite
imagery for Yachting Monthly's May 2016 edition. This article is still
online, and he kindly gave me permission to share a link to his blog with
you at
www.yachtingmonthly.com/sailing-skills/how-to-make-navigation-safer-using-sa
tellite-images-34665. (Note that my malwarebytes software regards gdayii.ca
as having possible vulnerabilities).
SAS Planet still allows comparison of various satellite imagery. A review of
how to use this as given in 2016 by Max of Fluenta,
sv-fluenta.blogspot.com/2016/11/using-satellite-imagery-to-assist.html
Here is a list of 5 "best" Marine Navigation Apps as judged by "discover
Boating" at
discoverboating.com/resources/marine-navigation-apps:
C-Map Embark
iNavX
KnowWake
Navionics
SeaPilot
Weather regimes - SAM
Us humans love finding patterns in things. Our orbit around the sun is so
repeatable and predictable that we have "seasons". Watching weather maps
long enough, one can see that sometimes the same weather system may repeat
in clusters. We like to watch for signs that predict changes.
Tonight, I'll blog about SAM, the southern annular mode. This is a measure
of the average speed of the westerly winds around the Polar vortex (the ring
of westerly winds that circle the planet between 50S and the Antarctic
circle (66 S). The value of SAM alters the north-south movement of this
vortex. A high positive value of SAM occurs when the air pressure over
Antarctica is lower than normal, and westerly winds in the polar vortex are
stronger than normal (note, the actual isobars over Antarctica are always
higher than those in the polar vortex, but SAM works with the anomaly
values, not the actual values). So, in a high positive SAM the polar vortex
is shifted southwards, and pressures is the mid-latitudes are higher than
normal, with weaker winds and settled weather.
As seen in blog.metservice.com/Southern-Annular-Mode
However, when SAM is negative, the polar vortex is weaker, and may spread
outwards, so that west to southwest winds over the mid-latitudes are
stronger than normal--- the chances are that there may be a POLAR BLAST.
SAM refers to surface winds 50S-66S. A proxy of SAM is available, namely the
AAO or Antarctic Annular mode (average 700hPa Z wind component 20S to 90S)
at
www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/aao/new.aao_inde
x_ensm.html
This has had a negative jump this week. This indicates a good chance of a
polar blast somewhere (not necessarily affecting NZ). Looking at EC data of
the surface air temperature on Windy tonight it seems that the polar blasts
this time are at 160W and 0 longitude as far north as 45-50 South-not much.
TROPICS
ELSA damaged the eastern seaboard of USA last week, and a downpour flooded
New York subways,
washingtonpost.com/nation/2021/07/09/new-york-flash-floods-subway/
No cyclones around at present, but there is a moderate build up of potential
development off the southwest of Mexico and around Cocos Island in the
Indian Ocean.
WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ is expected to be about average stretching from Solomon Islands to
Tonga, and minimal further east.
Two passing troughs for the South Pacific this week. The first one is
tonight east of New Caledonia and expected to cross Fiji/Tonga on local
Wednesday and fade over Southern Cooks on local Thursday. The second trough
is expected to cross the northern Tasman Sea on Friday and reach New
Caledonia on Saturday.
HIGHS and LOWS
HIGH 1022 east of NZ and south of southern Cooks traveling east along 25
to30S.
LOW 1000 near Norfolk Island tonight is expected to move SE over Northland
as 985 on Monday then off to the SE of NZ.
Next HIGH 1022 is expected to travel along 30S off Coffs around Tuesday and
past north of NZ on Thursday then further east.
Low 980 expected to form in south Tasman Sea by Friday and cross the South
Island on Saturday.
This recurring High-Low pattern is typical for winter.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more detail for 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 64277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 11 July 2021
In 2016 I introduced a series of blogs on the topic of "buffering" in Goggle
maps and how sometimes it shows open ocean where there are reefs. This data
saving tactic is called "Google lacunae"
Art of SV Feeling Good introduced us to OVITAL MAP which allows downloading
satellite images from various sources. Sadly, I have now been informed by
Eve of SV Auntie that Ovital Map has taken itself out of this business as it
now only uses Chinese satellites in which French Polynesia isn't covered.
Tom of Yacht Adina wrote a detailed account of navigating with satellite
imagery for Yachting Monthly's May 2016 edition. This article is still
online, and he kindly gave me permission to share a link to his blog with
you at
www.yachtingmonthly.com/sailing-skills/how-to-make-navigation-safer-using-sa
tellite-images-34665. (Note that my malwarebytes software regards gdayii.ca
as having possible vulnerabilities).
SAS Planet still allows comparison of various satellite imagery. A review of
how to use this as given in 2016 by Max of Fluenta,
sv-fluenta.blogspot.com/2016/11/using-satellite-imagery-to-assist.html
Here is a list of 5 "best" Marine Navigation Apps as judged by "discover
Boating" at
discoverboating.com/resources/marine-navigation-apps:
C-Map Embark
iNavX
KnowWake
Navionics
SeaPilot
Weather regimes - SAM
Us humans love finding patterns in things. Our orbit around the sun is so
repeatable and predictable that we have "seasons". Watching weather maps
long enough, one can see that sometimes the same weather system may repeat
in clusters. We like to watch for signs that predict changes.
Tonight, I'll blog about SAM, the southern annular mode. This is a measure
of the average speed of the westerly winds around the Polar vortex (the ring
of westerly winds that circle the planet between 50S and the Antarctic
circle (66 S). The value of SAM alters the north-south movement of this
vortex. A high positive value of SAM occurs when the air pressure over
Antarctica is lower than normal, and westerly winds in the polar vortex are
stronger than normal (note, the actual isobars over Antarctica are always
higher than those in the polar vortex, but SAM works with the anomaly
values, not the actual values). So, in a high positive SAM the polar vortex
is shifted southwards, and pressures is the mid-latitudes are higher than
normal, with weaker winds and settled weather.
As seen in blog.metservice.com/Southern-Annular-Mode
However, when SAM is negative, the polar vortex is weaker, and may spread
outwards, so that west to southwest winds over the mid-latitudes are
stronger than normal--- the chances are that there may be a POLAR BLAST.
SAM refers to surface winds 50S-66S. A proxy of SAM is available, namely the
AAO or Antarctic Annular mode (average 700hPa Z wind component 20S to 90S)
at
www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/aao/new.aao_inde
x_ensm.html
This has had a negative jump this week. This indicates a good chance of a
polar blast somewhere (not necessarily affecting NZ). Looking at EC data of
the surface air temperature on Windy tonight it seems that the polar blasts
this time are at 160W and 0 longitude as far north as 45-50 South-not much.
TROPICS
ELSA damaged the eastern seaboard of USA last week, and a downpour flooded
New York subways,
washingtonpost.com/nation/2021/07/09/new-york-flash-floods-subway/
No cyclones around at present, but there is a moderate build up of potential
development off the southwest of Mexico and around Cocos Island in the
Indian Ocean.
WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ is expected to be about average stretching from Solomon Islands to
Tonga, and minimal further east.
Two passing troughs for the South Pacific this week. The first one is
tonight east of New Caledonia and expected to cross Fiji/Tonga on local
Wednesday and fade over Southern Cooks on local Thursday. The second trough
is expected to cross the northern Tasman Sea on Friday and reach New
Caledonia on Saturday.
HIGHS and LOWS
HIGH 1022 east of NZ and south of southern Cooks traveling east along 25
to30S.
LOW 1000 near Norfolk Island tonight is expected to move SE over Northland
as 985 on Monday then off to the SE of NZ.
Next HIGH 1022 is expected to travel along 30S off Coffs around Tuesday and
past north of NZ on Thursday then further east.
Low 980 expected to form in south Tasman Sea by Friday and cross the South
Island on Saturday.
This recurring High-Low pattern is typical for winter.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more detail for 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 64277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
05 July 2021
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04 July 2021
Bob Blog 4 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 04 July
REVIEW OF THE LAST MONTH (June 2021)
The Sea surface temperatures are much as last month, but for a significant
warming around Europe and Japan. The warm seas around Japan are part of the
cause of their recent landslides.
The northern subtropical ridge has slightly intensified in the Atlantic and
moved onto Europe but has weakened elsewhere and retreated off Canada. In
the southern hemisphere the subtropical ridge has noticeably intensified,
especially over NZ, and extended both north and south. Pressures have
dropped over northern India in line with the Indian monsoon.
The belt of higher-than-normal pressure that stretched from Russia to
eastern Canada last month has gone. A new belt-of-higher-pressure now
extends from South Indian Ocean across NZ to southern South America.
The Canadian Heat wave
A good explanation of why NW America got so hot in the last week of June is
given at www.bbc.com/news/world-us-canada-57665715
Zooming into the NZ area
The subtropical ridge has extended northwards and southwards and intensified
to over 1020 over NZ. This brought a dry June to NZ but for a polar blast
early last week.
TROPICS
ELSA is over Cuba and expected to move over florid.
There are moderate zones of potential development off the southwest of
Mexico and around the Philippines.
WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ is expected to be about average stretching from Solomon Islands to
Samoa to Southern Cooks.
Two passing troughs for the South Pacific this week. The first one has
already got east of Niue and should travel east across Southern Cooks by
local Tuesday. The second trough is expected to reach New Caledonia on local
Tuesday and travel east over Tonga on local Thursday and reaching Tahiti on
local Sunday 11 July
HIGH 1036 over NZ tonight is expected to travel east along 40 to 45S.
FRONT in mid-Tasman Sea is expected to follow the HIGH and cross NZ on local
Tuesday followed by a S to southerly flow on Wednesday and Thursday.
Next HIGH is expected to move off New South Wales into the Tasman Sea on
Thursday and travel east over northern NZ on Saturday, followed by a LOW
deepening in that Tasman Sea on Sunday. This recurring Ridge-Trough pattern
is typical for winter.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more detail for 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 64277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.
Compiled Sunday 04 July
REVIEW OF THE LAST MONTH (June 2021)
The Sea surface temperatures are much as last month, but for a significant
warming around Europe and Japan. The warm seas around Japan are part of the
cause of their recent landslides.
The northern subtropical ridge has slightly intensified in the Atlantic and
moved onto Europe but has weakened elsewhere and retreated off Canada. In
the southern hemisphere the subtropical ridge has noticeably intensified,
especially over NZ, and extended both north and south. Pressures have
dropped over northern India in line with the Indian monsoon.
The belt of higher-than-normal pressure that stretched from Russia to
eastern Canada last month has gone. A new belt-of-higher-pressure now
extends from South Indian Ocean across NZ to southern South America.
The Canadian Heat wave
A good explanation of why NW America got so hot in the last week of June is
given at www.bbc.com/news/world-us-canada-57665715
Zooming into the NZ area
The subtropical ridge has extended northwards and southwards and intensified
to over 1020 over NZ. This brought a dry June to NZ but for a polar blast
early last week.
TROPICS
ELSA is over Cuba and expected to move over florid.
There are moderate zones of potential development off the southwest of
Mexico and around the Philippines.
WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ is expected to be about average stretching from Solomon Islands to
Samoa to Southern Cooks.
Two passing troughs for the South Pacific this week. The first one has
already got east of Niue and should travel east across Southern Cooks by
local Tuesday. The second trough is expected to reach New Caledonia on local
Tuesday and travel east over Tonga on local Thursday and reaching Tahiti on
local Sunday 11 July
HIGH 1036 over NZ tonight is expected to travel east along 40 to 45S.
FRONT in mid-Tasman Sea is expected to follow the HIGH and cross NZ on local
Tuesday followed by a S to southerly flow on Wednesday and Thursday.
Next HIGH is expected to move off New South Wales into the Tasman Sea on
Thursday and travel east over northern NZ on Saturday, followed by a LOW
deepening in that Tasman Sea on Sunday. This recurring Ridge-Trough pattern
is typical for winter.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more detail for 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 64277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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