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 28 September
A SSW (sudden stratospheric warming) in Antarctica.
The following notes are from https://www.weatherzone.com.au/news
The Polar vortex
The polar vortex extends from the surface up to the stratosphere, although
meteorologists typically refer to it in two distinct sections:
The stratospheric polar vortex sits about 10 to 50 km above Earth's surface.
This section of the polar vortex is strong and typically shaped like a
circle or oval. The stratospheric polar vortex does not directly affect
weather near Earth's surface.
The tropospheric polar vortex extends from the surface up to the bottom of
the stratosphere, spanning the lowest 8 to 12 km of the atmosphere. The
tropospheric polar vortex can directly influence weather patterns across the
southern and northern hemispheres by changing the shape and behaviour of the
polar jet stream.
Sudden stratospheric warming
The stratospheric polar vortex can become weakened and displaced by a
phenomenon called Sudden Stratospheric Warming (SSW), which refers to a
rapid increase in temperature in the polar stratosphere triggered by sinking
air. These stratospheric warming episodes sometimes filter downwards through
the atmosphere and can then disrupt the tropospheric polar vortex, causing
it to weaken and change shape.
When stratospheric warming causes the tropospheric polar vortex to weaken,
we usually see the polar jet stream become wavier and expand towards the
equator, which allows nodes of cold air to spread away from the polar region
into the mid-latitudes.
SSW episodes are common in the northern hemisphere, but they happen less
frequently in the southern hemisphere, where the polar vortex is stronger.
However, an episode of stratospheric warming is currently occurring above
Antarctica.
The animation below shows the evolution of the current stratospheric warming
in the southern hemisphere.
Video: Temperature and geopotential height of the 10 hPa pressure level
above Antarctica over the last three months, showing a previously stable
polar vortex being disrupted by stratospheric warming in September.
If the current episode of stratospheric warming filters downwards through
the atmosphere, it could cause the tropospheric polar vortex to weaken,
allowing southern hemisphere's polar jet stream to drag cold air away from
Antarctica. This jet stream pattern is associated with a negative phase of
the Southern Annular Mode (SAM)
I use the AAO (AntArctic Oscillation) as a proxy for SAM and indeed the GFS
ensemble patterns are showing it may well be negative next few weeks:
www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/aao/aao_index_en
sm.shtml
This would make the following conditions more likely in Australia/ South
Tasman Sea/South Island of New Zealand during late September and early
October:
More westerly winds= wet over the Southern Alps and hot and dry for
Canterbury plains.
Higher chance of abnormally hot days in southern Australia
Weatherzone's meteorologists will be keeping a close eye on the polar vortex
over the next couple of weeks.
TROPICS
The latest cyclone activity report is at zoom.earth and tropic.ssec.wisc.edu
and Tropical Cyclone Potential is
from https://www.ospo.noaa.gov/products/ocean/tropical/tcfp/
• Super Typhoon Ragasa became the world's strongest tropical cyclone of the
year, leaving at least 17 people dead in Taiwan and 10 others in the
Philippines. It later pounded Hong Kong.
• Typhoon Neoguri churned the waters of the northwestern Pacific, while
Hurricane Narda remained far off Mexico's coast.
• Hurricane Gabrielle and Tropical Storm Humberto passed over the Atlantic.
Weather Zones
Mid-week GFS model showing isobars, winds, waves (purple), rain (red), MT
(Monsoonal trough), STR (Subtropical Ridge), SPCZ (South Pacific Convergence
Zone) CZ (Convergence Zone)
Rain accumulation this week from Windy.com below is very similar to last
week. It shows well defined SPCZ between Solomon Islands and Funafuti and
again east of Samoa. It may shift south onto Samoa late in the week. A
passing trough is expected over the Southern Cooks and Austral Islands
There are several passing fronts in the roaring 40s.
Wind accumulation from windy.com below shows disturbed westerlies south of
30S, typical of spring. Some wind in the Coral Sea but no squash zone s in
the tropics. Maybe a lull around Suwarrow Island.
LOWS and HIGHS
There is a steady easterly migration with Low 1 going SE and High 1 slowly
following.
L2 and L3 and a series of associated fronts cross the NZ area. The main
fronts over Northland are expected on Monday night and on Friday/Saturday,
then Wed 8 oct. (avoid arriving then).
As for Australia HIGH H2 is expected to spend the second half of the week
traveling east along 32S onto South Australia.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, check metbob.com
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.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
28 September 2025
21 September 2025
Bobgram 21 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 21 September
There is a solar eclipse over NZ on Monday morning
And then the equinox is expected on Tuesday morning New Zealand time.
This year's Ozone hole
https://www.facebook.com/ECMWFcopernicus/videos/this-year-the-ozone-hole-pre
sented-an-early-development-reaching-a-larger-than-a/767656056069254/
Europe's Copernicus Atmosphere Monitoring Service says the ozone hole over
Antarctica formed earlier this year than in 2024, covering about 8 million
square miles during the first half of September. The service says the hole
grew larger than the long term average but did not reach anywhere near the
record size of 11.4 million square miles in 2006. The U.N. weather agency
says the layer of stratospheric ozone should recover to 1980 levels by
around 2066 over Antarctica, 2045 over the Arctic and 2040 for the rest of
the world.
The 'blob' is back - except this time it stretches across the entire North
Pacific
Based on the CNN write up at
https://edition.cnn.com/2025/09/19/climate/pacific-ocean-blob-hot-water-glob
al-warming
A record-breaking and astonishingly expansive marine heat wave is underway
in the Pacific Ocean, stretching about 5,000 miles from the water around
Japan to the West Coast of the United States. The abnormally warm "blob" of
ocean water, which is getting a significant boost from human-caused global
warming, is affecting the weather on land and could have ripple effects on
marine life.
The North Pacific warmed at the fastest rate of any ocean basin on Earth
during the past decade, according to Michael McPhaden, a senior scientist at
the National Oceanic and Atmospheric Administration.
And the entire North Pacific Ocean Basin is involved in the current marine
heat wave, standing out starkly on weather maps. This event is unique for
its intensity and extraordinary geographic reach, and for its potential to
eventually alter large-scale weather patterns if it continues.
In parts of the North Pacific, from the Gulf of Alaska south to the coast of
California, this heat wave is known as a "blob" of unusually hot water. It
is part of a pattern of marine heat waves in this area following a severe
heating event in 2013 that lasted until 2016. That heat wave remains the
most severe on record. It's warm waters extended deep into the upper layers
of the ocean, which allowed it to persist through the stormy winter months.
This one, however, is more likely to prove fleeting in the northeastern
Pacific since it is more surface-based. Winter storms should be about to
stir up cooler water and end this blob. Even so, it ranks as the
fourth-largest Northeast Pacific blob yet observed.
The cause of the ongoing marine heat wave is a "persistent anomalous wind
conditions" associated with stagnant high-and low-pressure areas. This
stagnation affects the discourage the normal upwelling pattern.
This increase in marine heat waves and accelerated warming in the North
Pacific Ocean is attributed to global warming pollution from burning fossil
fuels. The fingerprint of climate change is clearly evident in what is
transpiring now in the North Pacific.
TROPICS
The latest cyclone activity report is at zoom.earth and tropic.ssec.wisc.edu
and Tropical Cyclone Potential is from
https://www.ospo.noaa.gov/products/ocean/tropical/tcfp/
In the north Atlantic: Tropical Storm Mario passed off Mexico's Pacific
coast, while Gabrielle spun up in the mid-Atlantic Ocean after weeks of
unusual calm during the normal peak of the Atlantic hurricane season.
In the western Pacific: RAGASSA is crossing the Philippines and NEOGURI is
moving off to the Northeast.
Weather Zones
Mid-week GFS model showing isobars, winds, waves (purple), rain (red), MT
(Monsoonal trough), STR (Subtropical Ridge), SPCZ (South Pacific Convergence
Zone) CZ (Convergence Zone)
Rain accumulation this week from Windy.com below is very similar to last
week. It shows well defined SPCZ between Solomon Islands and Funafuti and
again east of Samoa. It may shift south onto Samoa late in the week.
The fronts crossing NZ are expected to drop another week of intense rain
over the Southern alps, topping up the hydro lakes. Australia is looking to
have a dry week.
Wind accumulation from windy.com below shows disturbed westerlies south of
30S, typical of spring. Some wind in the Coral Sea but no squash zone s in
the tropics. Maybe a lull around Suwarrow Island.
LOWS and HIGHS
There is a steady easterly migration with Low 1 going SE and High 1 slowly
following.
As for NZ area, a series of fronts are expected there from Monday to
Wednesday, followed by a westerly flow on Thursday and then another front on
Friday.
As for Australia HIGH H2 is expected to start the week in Aussie bight then
travel northeast across the continent reaching Queensland on Thursday then
weakening as it travels across the Tasman Sea and then goes east along 30S
north of NZ this weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, check metbob.com
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 21 September
There is a solar eclipse over NZ on Monday morning
And then the equinox is expected on Tuesday morning New Zealand time.
This year's Ozone hole
https://www.facebook.com/ECMWFcopernicus/videos/this-year-the-ozone-hole-pre
sented-an-early-development-reaching-a-larger-than-a/767656056069254/
Europe's Copernicus Atmosphere Monitoring Service says the ozone hole over
Antarctica formed earlier this year than in 2024, covering about 8 million
square miles during the first half of September. The service says the hole
grew larger than the long term average but did not reach anywhere near the
record size of 11.4 million square miles in 2006. The U.N. weather agency
says the layer of stratospheric ozone should recover to 1980 levels by
around 2066 over Antarctica, 2045 over the Arctic and 2040 for the rest of
the world.
The 'blob' is back - except this time it stretches across the entire North
Pacific
Based on the CNN write up at
https://edition.cnn.com/2025/09/19/climate/pacific-ocean-blob-hot-water-glob
al-warming
A record-breaking and astonishingly expansive marine heat wave is underway
in the Pacific Ocean, stretching about 5,000 miles from the water around
Japan to the West Coast of the United States. The abnormally warm "blob" of
ocean water, which is getting a significant boost from human-caused global
warming, is affecting the weather on land and could have ripple effects on
marine life.
The North Pacific warmed at the fastest rate of any ocean basin on Earth
during the past decade, according to Michael McPhaden, a senior scientist at
the National Oceanic and Atmospheric Administration.
And the entire North Pacific Ocean Basin is involved in the current marine
heat wave, standing out starkly on weather maps. This event is unique for
its intensity and extraordinary geographic reach, and for its potential to
eventually alter large-scale weather patterns if it continues.
In parts of the North Pacific, from the Gulf of Alaska south to the coast of
California, this heat wave is known as a "blob" of unusually hot water. It
is part of a pattern of marine heat waves in this area following a severe
heating event in 2013 that lasted until 2016. That heat wave remains the
most severe on record. It's warm waters extended deep into the upper layers
of the ocean, which allowed it to persist through the stormy winter months.
This one, however, is more likely to prove fleeting in the northeastern
Pacific since it is more surface-based. Winter storms should be about to
stir up cooler water and end this blob. Even so, it ranks as the
fourth-largest Northeast Pacific blob yet observed.
The cause of the ongoing marine heat wave is a "persistent anomalous wind
conditions" associated with stagnant high-and low-pressure areas. This
stagnation affects the discourage the normal upwelling pattern.
This increase in marine heat waves and accelerated warming in the North
Pacific Ocean is attributed to global warming pollution from burning fossil
fuels. The fingerprint of climate change is clearly evident in what is
transpiring now in the North Pacific.
TROPICS
The latest cyclone activity report is at zoom.earth and tropic.ssec.wisc.edu
and Tropical Cyclone Potential is from
https://www.ospo.noaa.gov/products/ocean/tropical/tcfp/
In the north Atlantic: Tropical Storm Mario passed off Mexico's Pacific
coast, while Gabrielle spun up in the mid-Atlantic Ocean after weeks of
unusual calm during the normal peak of the Atlantic hurricane season.
In the western Pacific: RAGASSA is crossing the Philippines and NEOGURI is
moving off to the Northeast.
Weather Zones
Mid-week GFS model showing isobars, winds, waves (purple), rain (red), MT
(Monsoonal trough), STR (Subtropical Ridge), SPCZ (South Pacific Convergence
Zone) CZ (Convergence Zone)
Rain accumulation this week from Windy.com below is very similar to last
week. It shows well defined SPCZ between Solomon Islands and Funafuti and
again east of Samoa. It may shift south onto Samoa late in the week.
The fronts crossing NZ are expected to drop another week of intense rain
over the Southern alps, topping up the hydro lakes. Australia is looking to
have a dry week.
Wind accumulation from windy.com below shows disturbed westerlies south of
30S, typical of spring. Some wind in the Coral Sea but no squash zone s in
the tropics. Maybe a lull around Suwarrow Island.
LOWS and HIGHS
There is a steady easterly migration with Low 1 going SE and High 1 slowly
following.
As for NZ area, a series of fronts are expected there from Monday to
Wednesday, followed by a westerly flow on Thursday and then another front on
Friday.
As for Australia HIGH H2 is expected to start the week in Aussie bight then
travel northeast across the continent reaching Queensland on Thursday then
weakening as it travels across the Tasman Sea and then goes east along 30S
north of NZ this weekend.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, check metbob.com
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.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
14 September 2025
Bobgram
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 14 September
A more indicative measure of ENSO
ENSO stands for ElNinoSouthernOsciallation
The EN part of this parameter deals with sea temperature. We have been using the sea surface temperature measured in the Nino3-4 area as the parameter for deciding if the atmosphere is being driven by El Nino or La Nino or is in between the two in neutral gear. The SO part deals with the isobaric pressure difference between Darwin and Tahiti… located on this map:
However, climate change has been raising the world's average sea temperate in a roller-coaster fashion
Too try and remove this trend from the measurements, BoM have introduced a new measure called the RELATIVE NINO INDICIES.
As seen on their web site https://www.bom.gov.au/climate/enso/
Relative Niño indices
Traditional Niño index values were used at the Bureau of Meteorology until September 2025. From September 2025, the Bureau uses Relative Niño indices, which measure sea surface temperature anomalies in the tropical Pacific Ocean in the Niño regions, but calculated relative to the global tropical region temperature anomaly. This is to relate the indices more closely to the localised processes associated with ENSO, rather than larger-scale tropical SST features such as global warming.
Example: The Relative Niño3.4 index calculation:
Relative Niño3.4 = S x [(Niño3.4obs – Niño3.4clim) – (Tropical Meanobs – Tropical Meanclim)]
Where Niño3.4obs and Tropical Meanobs are the SST averages over the Niño3.4 region and the 20°S to 20°N tropical mean SST, respectively, while Niño3.4clim and Tropical Meanclim are the climatological values for the appropriate day/month depending on the dataset. S is a scaling factor applied so the variance of the relative Niño index matches that of the traditional index.
Sustained monthly Relative Niño3 or Niño3.4 index values above +0.8 °C as typical of El Niño conditions, with values of below −0.8 °C as typical of La Niña. These values are approximately one standard deviation from the long-term mean (e.g., around 70% of all monthly Niño3.4 values, lie between −0.8 °C and +0.8 °C).
This is what REL NINO 3-4 looks like going back to April 2021
It gives a good view of the El Nino in late 23/early 24
and the La Nina of late24/early 25 and shows a neutral trend in recent data.
BoM reports that there is now a negative IOD event and it is expected to continue during spring, until at least the next month. This is likely to bring wet conditions to parts of southern and eastern Australia.
TROPICS
The latest cyclone activity report is at zoom.earth and tropic.ssec.wisc.edu and Tropical Cyclone Potential is from https://www.ospo.noaa.gov/products/ocean/tropical/tcfp/
•A tornado spawned by Tropical Storm Peipah southwest of Tokyo tore roofs off homes and flipped cars.
• China's Guangdong province was drenched by Typhoon Tapah
• Hurricane Kiko weakened to a tropical storm just before skirting the northern Hawaiian Islands.
• MARIO is moving out to sea off south of Baja California.
Weather Zones
Mid-week GFS model showing isobars, winds, waves (purple), rain (red), MT (Monsoonal trough), STR (Subtropical Ridge), SPCZ (South Pacific Convergence Zone) CZ (Convergence Zone)
Rain accumulation this week from Windy.com below shows well defined SPCZ between Solomon Islands and Funafuti and again east of Samoa. The eastern branch is forecast to shift south and form a depression L1 near the Southern Cooks late in the week.
Intense rain is forecast for Southern Alps in New Zealand especially with trough 2 on Tuesday and Wednesday.
Wind accumulation from windy.com below shows a windy area from Samoa to Southern Cooks late in the week with development of L1 from off the SPC. The disturbed westerlies south of 35S are typical of spring.
LOWS and HIGHS
There is a steady easterly migration with trough 1 followed by H1, then trough 2 and High2 then trough 3.
Trough 2 is expected over NZ on Tuesday and Wednesday preceded by NW winds, accompanied by rain heavy over the mountains and followed by a day or so of chilly SW winds. Then H2 crosses north island on Friday and Saturday. The sequence then repeats next week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, check metbob.com
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 14 September
A more indicative measure of ENSO
ENSO stands for ElNinoSouthernOsciallation
The EN part of this parameter deals with sea temperature. We have been using the sea surface temperature measured in the Nino3-4 area as the parameter for deciding if the atmosphere is being driven by El Nino or La Nino or is in between the two in neutral gear. The SO part deals with the isobaric pressure difference between Darwin and Tahiti… located on this map:
However, climate change has been raising the world's average sea temperate in a roller-coaster fashion
Too try and remove this trend from the measurements, BoM have introduced a new measure called the RELATIVE NINO INDICIES.
As seen on their web site https://www.bom.gov.au/climate/enso/
Relative Niño indices
Traditional Niño index values were used at the Bureau of Meteorology until September 2025. From September 2025, the Bureau uses Relative Niño indices, which measure sea surface temperature anomalies in the tropical Pacific Ocean in the Niño regions, but calculated relative to the global tropical region temperature anomaly. This is to relate the indices more closely to the localised processes associated with ENSO, rather than larger-scale tropical SST features such as global warming.
Example: The Relative Niño3.4 index calculation:
Relative Niño3.4 = S x [(Niño3.4obs – Niño3.4clim) – (Tropical Meanobs – Tropical Meanclim)]
Where Niño3.4obs and Tropical Meanobs are the SST averages over the Niño3.4 region and the 20°S to 20°N tropical mean SST, respectively, while Niño3.4clim and Tropical Meanclim are the climatological values for the appropriate day/month depending on the dataset. S is a scaling factor applied so the variance of the relative Niño index matches that of the traditional index.
Sustained monthly Relative Niño3 or Niño3.4 index values above +0.8 °C as typical of El Niño conditions, with values of below −0.8 °C as typical of La Niña. These values are approximately one standard deviation from the long-term mean (e.g., around 70% of all monthly Niño3.4 values, lie between −0.8 °C and +0.8 °C).
This is what REL NINO 3-4 looks like going back to April 2021
It gives a good view of the El Nino in late 23/early 24
and the La Nina of late24/early 25 and shows a neutral trend in recent data.
BoM reports that there is now a negative IOD event and it is expected to continue during spring, until at least the next month. This is likely to bring wet conditions to parts of southern and eastern Australia.
TROPICS
The latest cyclone activity report is at zoom.earth and tropic.ssec.wisc.edu and Tropical Cyclone Potential is from https://www.ospo.noaa.gov/products/ocean/tropical/tcfp/
•A tornado spawned by Tropical Storm Peipah southwest of Tokyo tore roofs off homes and flipped cars.
• China's Guangdong province was drenched by Typhoon Tapah
• Hurricane Kiko weakened to a tropical storm just before skirting the northern Hawaiian Islands.
• MARIO is moving out to sea off south of Baja California.
Weather Zones
Mid-week GFS model showing isobars, winds, waves (purple), rain (red), MT (Monsoonal trough), STR (Subtropical Ridge), SPCZ (South Pacific Convergence Zone) CZ (Convergence Zone)
Rain accumulation this week from Windy.com below shows well defined SPCZ between Solomon Islands and Funafuti and again east of Samoa. The eastern branch is forecast to shift south and form a depression L1 near the Southern Cooks late in the week.
Intense rain is forecast for Southern Alps in New Zealand especially with trough 2 on Tuesday and Wednesday.
Wind accumulation from windy.com below shows a windy area from Samoa to Southern Cooks late in the week with development of L1 from off the SPC. The disturbed westerlies south of 35S are typical of spring.
LOWS and HIGHS
There is a steady easterly migration with trough 1 followed by H1, then trough 2 and High2 then trough 3.
Trough 2 is expected over NZ on Tuesday and Wednesday preceded by NW winds, accompanied by rain heavy over the mountains and followed by a day or so of chilly SW winds. Then H2 crosses north island on Friday and Saturday. The sequence then repeats next week.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, check metbob.com
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.
>>>>>>>>>>>>>>>>
07 September 2025
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 07 September
Blood moon tonight
We are having a full moon locally Monday morning (6am in Auckland). And lunar perigee (closest earth-moon distance for the month) is on Wednesday. The moon is passing thru the earth's shadow tonight= a lunar eclipse. And since we are near perigee the moon is larger than normal so will receive some light that has gone thru the earth's atmosphere when in the outer or penumbral ring of the earth's shadow. This light is a brownish red (the blue part of its spectrum has been scattered away). Hence we are having A BLOOD MOON.
Timing in UTC on 7 September 2025
P1 Penumbral begins 1528UTC
U1 Partial begins 1627UTC
U2 Total begins 1730UTC
GE Greatest eclipse 1811UTC
U3 Total ends 1852UTC
U4 Partial ends 1956UTC
P4 Penumbral ends 2055 UTC
Moonset in Auckland is at 6:37am/ 1837UTC and in Sydney at 6:11am/2011UTC
So the kiwi may see a brief reddish glow on the setting moon, and the kangaroo gets to see most of the eclipse --- if the clouds don't get in the way.
A fortnight later we get the corresponding solar eclipse (moon shadow) which will be visible in New Zealand.
The sun will rise already partially eclipsed on Mon 22 Sep. In Auckland about 60% of the sun's disk will be covered. in Stewart Island as much as 75%
And this solar eclipse occurs one day before the vernal equinox.
TROPICS
. Minimal Tropical Storm Nongfa drenched parts of Vietnam that were already left soggy by Typhoon Kajiki a week before.
. Hurricane Kiko intensified to Category-3 force midway between Baja California and Hawaii and is expected to take a path north of Hawaii.
. Hurricane Lorena raked Baja California
Weather Zones
Rain accumulation this week from Windy.com shows well defined SPCZ between Solomon Islands and Funafuti. There is a passing trough early this week between Tonga and Niue weakening late in the week over Southern Cooks and another over southern French Polynesia.
Wind accumulation from windy.com shows a windy area south of French Polynesia, and another over Coral Sea and west of Vanuatu. There are some gale wind zones southwest of NZ on the backside of L2 and also on the backside of L1.
Equinoctial gales.
LOWS and HIGHS
LOW L1 crossed NZ on Saturday and is expected to travel steadily to the east. Associated trough in the tropics expected to spread from Tonga to Niue next few days then fade over Southern Cooks. It is followed by a burst of rough SW swell.
HIGH H1 is expected to travel east and drift south to 35S.
Low L2 should travel quickly along 50S crossing NZ mid-week.
HIGH H2 is expected to travel east to northeast between 35S and 25S following the trough of L1.
Low L3 is expected to deepen into a storm over Vic/NSW on Wednesday and then weaken as it crosses the Tasman Sea May reach North Island on Friday, followed by a strong southwest flow.
H3 is expected to follow L3 across Vic/NSW by the weekend then travel NE across the Tasman Sea.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, check metbob.com
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 07 September
Blood moon tonight
We are having a full moon locally Monday morning (6am in Auckland). And lunar perigee (closest earth-moon distance for the month) is on Wednesday. The moon is passing thru the earth's shadow tonight= a lunar eclipse. And since we are near perigee the moon is larger than normal so will receive some light that has gone thru the earth's atmosphere when in the outer or penumbral ring of the earth's shadow. This light is a brownish red (the blue part of its spectrum has been scattered away). Hence we are having A BLOOD MOON.
Timing in UTC on 7 September 2025
P1 Penumbral begins 1528UTC
U1 Partial begins 1627UTC
U2 Total begins 1730UTC
GE Greatest eclipse 1811UTC
U3 Total ends 1852UTC
U4 Partial ends 1956UTC
P4 Penumbral ends 2055 UTC
Moonset in Auckland is at 6:37am/ 1837UTC and in Sydney at 6:11am/2011UTC
So the kiwi may see a brief reddish glow on the setting moon, and the kangaroo gets to see most of the eclipse --- if the clouds don't get in the way.
A fortnight later we get the corresponding solar eclipse (moon shadow) which will be visible in New Zealand.
The sun will rise already partially eclipsed on Mon 22 Sep. In Auckland about 60% of the sun's disk will be covered. in Stewart Island as much as 75%
And this solar eclipse occurs one day before the vernal equinox.
TROPICS
. Minimal Tropical Storm Nongfa drenched parts of Vietnam that were already left soggy by Typhoon Kajiki a week before.
. Hurricane Kiko intensified to Category-3 force midway between Baja California and Hawaii and is expected to take a path north of Hawaii.
. Hurricane Lorena raked Baja California
Weather Zones
Rain accumulation this week from Windy.com shows well defined SPCZ between Solomon Islands and Funafuti. There is a passing trough early this week between Tonga and Niue weakening late in the week over Southern Cooks and another over southern French Polynesia.
Wind accumulation from windy.com shows a windy area south of French Polynesia, and another over Coral Sea and west of Vanuatu. There are some gale wind zones southwest of NZ on the backside of L2 and also on the backside of L1.
Equinoctial gales.
LOWS and HIGHS
LOW L1 crossed NZ on Saturday and is expected to travel steadily to the east. Associated trough in the tropics expected to spread from Tonga to Niue next few days then fade over Southern Cooks. It is followed by a burst of rough SW swell.
HIGH H1 is expected to travel east and drift south to 35S.
Low L2 should travel quickly along 50S crossing NZ mid-week.
HIGH H2 is expected to travel east to northeast between 35S and 25S following the trough of L1.
Low L3 is expected to deepen into a storm over Vic/NSW on Wednesday and then weaken as it crosses the Tasman Sea May reach North Island on Friday, followed by a strong southwest flow.
H3 is expected to follow L3 across Vic/NSW by the weekend then travel NE across the Tasman Sea.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, check metbob.com
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.
>>>>>>>>>>>>>>>>
Subscribe to:
Posts (Atom)