Bobgram 8 Dec

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 8 December 2024

This stuttering LA NINA

The sea service temperatures in the eastern equatorial Pacific are
slightly cooler than normal and holding steady at around -0.4C
off-normal, but are NOT expected to cool far enough to produce a full
blown La Nina.

BoM data from late November shows a plume of expected predictions from
several models, but only a few of them break the -0.8C threshold, and
most show a relaxing of conditions after end of January.

It now seems likely that this LA NINA event is a weak one and is
having minimal impact on weather as compared to previous episodes.

TROPICS
FENGAL tracked across Sri Lanka and Southern India last week.

No cyclones are around at present.

MJO is now travelling eastwards across Indonesia and northern
Australia.

WEATHER ZONES
The wind accumulation shows a couple of windy fronts near North
Island, NZ, this week and windy conditions generally south of 40S. The
tropics look OK except for strong winds and heavy around Niue and
Southern Cooks associated with a tropical depression late in the week.

The South Pacific Convergence zone extends from Northern Vanuatu to
north of Samoa to an active region over Southern Cooks Tropical Low L2
is expected to deepen and travel SE of southern cooks by end of week.
Another low L3 may form over New Caledonia area late in the week and
travel southeast crossing North Island around Sunday 15 Dec.

When the MJO starts arriving over north Australia and into the Pacific
over the next few weeks, more active tropical weather is likely.

HIGHS and LOWS

This is a good week for a NW steering field on our weather features.

HIGH H1 may stay quasi stationary well to southeast of Tahiti. The
HIGH H2 east of NZ should travel southeast well east of NZ this week.

The trough crossing NZ tonight and Monday is expected to peel off to
the southeast next few days.

Low L1 should travel off the heat trough over central Australia and
form near Lord Howe by Wednesday then travel weaken into a trough
crossing NZ on Thursday.

HIGH H3 should be over Aussie Bight by Wednesday and into central
Tasman Sea/ Southern NZ area by Saturday.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about 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 text 64277762212.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>