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 16 Nov 2025

TROPICS


Nothing on the map tonight, but models are watching clouds gathering in
Timor Sea and something might form from that near Darwin late this week.



In the past week.
. Typhoon Kalmaegi left 188 people dead in record flooding across the
central Philippines, and then struck storm-weary central Vietnam as a
Category 4 storm, tearing roofs off homes and killing five more.
. Kalmaegi was quickly followed by Typhoon Fungwong, which killed 27 people
in northern Philippine floods. It later caused severe flooding across Taiwan
as a tropical storm.


WEATHER ZONES


Rain accumulation this week from Windy.com below shows well defined and
increasingly active SPCZ expanding southwards. Also, a possible cyclone near
Darwin late this week.

Wind accumulation from windy.com above shows the possible path of possible
tropical cyclone late this week near Darwin. Also, the HIGH east of NZ, the
trough area between New Caledonia and Northland, and the squash zone of
enhanced winds between these two systems.


LOWS and HIGHS
HIGH H1 east of NZ over 1032 is quasi stationary near 40S 160W with a rim of
enhanced winds (squash zone) on its northern to western edge.
Left of the squash zone is a trough region, especially between the tropic
and Northland. A low may form in this area early next week.
Low L1 belongs to a front which is tonight in the mid Tasman sea and on
Monday/Tuesday may stretch from New Caledonia to the South Island and then
fade over the North Island.
High H2 starts off in Australian Bight and by Wednesday is in mid Tasman
Sea. Later in the week it may stall over central New Zealand.

HIGH H2 is expected to travel across Aussie Bight early this week and then
go northeast from New South Wales to northern NZ by the weekend with a
westerly flow on its southern side.
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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.
>>>>>>>>>>>>>>>>

Bobgram 9 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 09 Nov 2025
Things missing from marine weather forecasts

Marine forecasts give a situation statement that lists the location o=and
movement of features seen on weather maps. Highs, Lows, Convergence zones
and fronts. The give warnings of areas with gales or stronger, heavy swells,
and freezing conditions.
There are two things they don't give, but sailors would like to know about.
to know about.

1) Lightning
2) Sunburn

1)If you have access to Internet and web sites then windy.com and
Predictwind.com do include lightning maps
The Predictwind map combines lightning and satellite imagery with the GMDSS
(Global Maritime Distress and Safety System) warning and situation maps

From forecast.predictwind.com/satellite-imagery/
Turn lightning on in the map options.

Windy.com offers several global models and displays their wind, isobars,
rain and lightning on the same map along with observations.
For people visiting the cruising grounds of New Zealand Weatherwatch have
compiled a special page for lightning
www.weatherwatch.co.nz/maps-radars/lightning/thunderstorm-risk
Combining observations from Blitzortung and MetService (coming soon) with
a CAPE
(Convective available potential energy) and SLI (Surface lifted index) and
the latest MetService Thunderstorm outlook.

This can be a useful place to check before sailing.

2). The NZ atmosphere has less haze that other places and thus higher UV.
As for the intensity of the sunburn, Earth Science NZ has put together the
following web page
niwa.co.nz/atmosphere/uv-and-ozone/uv-and-ozone/todays-uv-index

This can be used retrospectively. SO, if you do get sunburnt then check
this site and it shows the measured UV compared with the predicted UV cloud




TROPICS


Tonight there is 1 named storms, FUNG-WONG approaching Taiwan


In the past week.
. At least 140 people died during catastrophic flooding in the central
Philippines from Typhoon Kalmaegi, one of the strongest to hit the country
this year.
. Typhoon Fung-wong formed between the Pacific islands of Guam and Yap



WEATHER ZONES
Rain accumulation this week from Windy.com below shows well defined and
increasingly active SPCZ mainly in the north but visiting Fiji and Tonga at
times.

Wind accumulation from windy.com above shows even winds in the tropics, but
for a squash zone over southern parts of French Polynesia and wind
associated with L1.
Also, the Tasman Sea is windy, but elsewhere the wind zone is drifting to
the south.


LOWS and HIGHS
Low L1 East of Kermadecs is moving slowly to southeast whilst HIGH H1
travels quickly east along 43S.
The Trough and Low in the Tasman sea tonight is expected to travel east
across NZ on Monday and leave behind a low L2 that forms over Lord Howe area
on Tuesday and then travels east across NZ on Wednesday and Thursday.
HIGH H2 is expected to travel across Aussie Bight early this week and then
go northeast from New South Wales to northern NZ by the weekend with a
westerly flow on its southern side.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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.
>>>>>>>>>>>>>>>>

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 02 Nov 2025
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 youtu.be/F-RXc9_fBFE
It was very zonal month, with trade winds in the tropics, a well
identified subtropical ridge near 25 to 30S and disturbed westerlies south
of 35S. Lows crossed NZ on 4, 23 and 27 October. The 23 OCT Low was special,
at 958hPa near Invercargill, so 40hPa of isobars between Auckland and
Invercargill. The speed of the movement of the low itself was added to the
wind over southland and some anemometers measured over 200 kph.
The Low on 23 October :


The 500hPa heights and anomalies shows these Lows.
From http://www.cpc.ncep.noaa.gov/products/intraseasonal/z500_sh_anim.shtml

Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml
The North Pacific "blob" is still there, but there is now some colder
surface water north of Korea. The equatorial Pacific is slightly cooler,
and Coral Sea is noticeably warmer.

TROPICS

Tonight there is 1 named storms, KALMAEGI crossing the Philippines.

In the past few weeks.
. Super Hurricane Melissa ravaged western Jamaica as the most powerful storm
ever to strike the country. Melissa then weakened before pounding Cuba, the
Bahamas and Bermuda.
. India's central Bay of Bengal coast was drenched by Tropical Storm Montha.
. Tropical Storm Sonia formed in the eastern Pacific.

WEATHER ZONES

Rain accumulation this week from Windy.com below shows well defined SPCZ
mainly in the north but visiting Fiji and Tonga and connected to a low form
the tropics labelled L3.

Wind accumulation from windy.com above shows even winds in the tropics, a
well- defined subtropical ridge over Coral sea to Auckland, and winds around
a Low L3 between Fiji and Minerva plus along 30S just north of NZ.

LOWS and HIGHS
Low L1 well southeast of NZ is expected to move slowly over Southern Ocean
as HIGH H1 now just NE of Auckland travels ENE along 35 to 30S.
Low L2 is expected to stall over Tasmania/Victoria area until after the
Tuesday Melbourne Cup and then to travel SE to southern Tasman as High H3
zips around its northside and crosses central NZ this weekend. Then L2 may
stall over whole of NZ early next week.
Low L3 is expected to form over Tonga area by midweek and then maybe partly
go west and partly go east. Central pressure around 1010 so rather weak
but may breed squalls,
Low L4 from the tropics is expected to deepen intensely over Perth area
mid-week then shoot off to the southeast where it may merge with L2 over NZ
next week.
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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.
>>>>>>>>>>>>>>>>