Bob blog 27 March

Bob Blog 27 Mar
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 March 2022
Beware the triple point
Northern and eastern parts of North Island had record rainfalls to mark the
equinox om 21-22 March. The MetService weather station on Purerua peninsula,
northeast of Kerikeri, recorded 93mm in one hour (12:30 and 1:30am).
Maungatapere, just inland from Whangarei, recorded 123.2mm between 3:30and
4:30am. (NZ national record for one hour rainfall is 134mm held by Cropp
between Hokitika and Mount Cook, 8 Jan 2004).

The deluge came from a narrow band of thundery showers marking where the air
around a low collides with air around a high.

Looking closely at the animation of the daily weather maps (see
www.youtube.com/watch?v=vkO3jfcsD1w) shows frontal details. The TRIPLE POINT
is where a cold front catches up with a warm front and starts producing an
occluded front.

The illustrated blog at metbob.wordpress.com/2022/03/27/bob-blog-27-mar/
shows an accumulated rainfall map for NZ for the week ending 24 March from
MetService with the path of a triple point. The purple area on the rain map
is over 200mm

So, when you see a triple point on a weather map, BEWARE.

TROPICS
There is an active phase of MJO pulse in the Indian Ocean moving onto
northern Australia.
TC CHARLOTTE formed northwest of Australia last week and stayed offshore and
faded.
HALIMA is traveling southeast over the open sea.

WEATHER ZONES
SPCZ=South Pacific Convergence zone.
The SPCZ stretches from PNG to Vanuatu to Fiji/Tonga to Southern Cooks.
A trough L3 is expected to form over Vanuatu by mid-week and then travel
southeast over Fiji by Friday.

HIGHS and LOWS
Low1 is a continuation of last weeks Tasman Low and is now expected to be
kicked north then east.
High H1 east of NZ is expected to travel off to the east.
Low L2 is expected to form northeast of Brisbane on Monday and then deepen
and travel southeast across the Tasman Sea, producing strong winds and
swells up to 5m reaching the North Island this weekend then followed by
southerly winds. L2 offers a good pattern for getting from Aussie to New
Caledonia.
High H2 is waiting in the Aussie Bight for the southerly winds after L2 to
reach NZ and then is expected to cross the Tasman next week along 40S.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>