Bob McDavitt's ideas for sailing weather around the South pacific

12 October 2008

BOBGRAM7 issued 12 Oct 2008

Issued 12 Oct 2008
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos, these ideas come from
the patterned world of weather maps, so please fine-tune to your place.
Dates below are given in UTC unless otherwise stated.

October's full moon is on the 15th - good for cruising. During the
following week, induced by the spring tides a few days after that full
moon, there will be a few nights where the annual PALOLO RISING (in Fiji
the BALOLO RISING) may occur when coral worms spawn. Worth checking
out, ask the locals. And the New Moon on the 29th is marked with the
Hindu Festival of Lights - rather dark for cruising.

The annual analysis paralysis season is about to start as cruisers in
Tonga gather all their ideas together to try and pick the 'best' time to
leave for NZ. My ideas will be just part of this, and I have no ideas
beyond 24 Oct at this stage.

TROPICS The South pacific Convergence Zone, SPCZ, extends from Solomons/
Coral Sea to Wallis/Futuna to central Tonga to a LOW that has formed
south of Niue. - There is a weaker branch from Samoa to Northern Cooks.
That Low south of Niue is expected to fade where it is on Monday. The
area should remain troughy with a squash zone near 30S 150 to 170W as a
big fat high moves east of NZ and bananas-around it at 40S, 14th to 16th
Oct. Avoid this squash zone - but is should generate some useful swell
for surfers in Bay of Plenty/ Bay of Islands for 18/19 Oct (this isn't
being picked by the computers but I think it's a good possibility). The
troughy area should reforms that Low near 30S 160W on 16th as that high
moves further East, and the LOW should be captured by the next
mid-latitude trough and go off to the SE-associated trough should bother
Niue on 15 Oct and may bother Southern cooks on 16-17 oct. Take care.

SPCZ is moving south across Coral Sea and computers are picking it may
develop a trough visiting New Caledonia 15 to 17 Oct and Southern Tonga
17 to 19 Oct. Squally showers, and appears in those GRIB files as a
deceptive zone of light variable winds. Avoid.

One migratory HIGH is moving along 40S across NZ on 12-13 Oct and then
off to the east 14-17 Oct. Its squash zone is being focused at 30S by
that troughy region south of Niue.

Between Highs, a trough should broaden over NZ 16-18 Oct.

Next subtropical HIGH is expected to form in Tasman Sea 16 oct and move
northeast and fade over Lord Howe area 19 Oct-it is a brief one, but
good for Tasman sea sailing.

Next trough broadens over NZ area 20-24 Oct and since the next HIGH
seems likely to form in the Tasman Sea at 40S , that would suggest a
cold southerly over NZ on 23-24 Oct. Avoid.

Sailing to NZ? Try and arrange your arrival to be WITH the HIGHs
(13-15, 18-19, 24-26 Oct).

The terms used are more fully explained in the METSERVICE Yacht Pack.
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