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

06 August 2017

Bob Blog 6 Aug 2017

Compiled Sun 6 Aug 2017

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.

NORU is still going and is expected to visit Japan this week, and NALGAR is over the open ocean further east. There are two tropical depressions on the Atlantic Ocean that may develop further during the coming week. We can see these at

Last week's rain map, compared with the week before, shows continuing high rainfall around Japan, the equatorial Indian Ocean, and possibly the equatorial Atlantic ocean, and decreasing amounts elsewhere.

Rain for the past fortnight from

SPCZ=South Pacific Convergence zone.
The SPCZ starts this week draped from Solomon Islands to Tuvalu and Tokelau Islands to Northern Cooks. An MJO event is moving into the western Pacific this week and that should help activate the SPCZ.
A convergence zone /trough is expected to travel east across the Society Islands on local Monday. Better to stay put for that and depart local Tuesday.
Next trough from the west is expected to reach New Caledonia on local Wednesday and Tonga area on local Friday, it's a minor trough but worthy of consideration.

Subtropical ridge (STR)
High east of NZ is expected to travel east along 30s until Thursday and then weaken as a High from further south builds around 160W.
New High is expected to move off eastern Australia into North Tasman Sea on Thursday, and travel along 28S past norther NZ by Saturday 12 Aug.

Between Australia /NZ and the tropics:
Low is expected to travel east along 40S from Monday to Wednesday across Southern Tasman sea. Moving southeast across central NZ on Thursday.

French Polynesia to the west:
A trough/convergence zone that is expected to be crossing the Society Islands on local Monday UTC. Wait until TUESDAY and its should be ok to go west from Society islands.
The SPCZ is expected to be mainly confined to the Solomon Islands to Tokelau Islands area, but may extend to Suwarrow by end of the week.

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