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 1 June 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 at
youtu.be/TZUof6eDnBY

The highlight of the month for the South Pacific tropics was a chain
of lows that formed around 10 May.  Further south it was a series of
Lows and Highs

The 500hPa heights and anomalies shows last month's typical ridge
/trough pattern,

From http://www.cpc.ncep.noaa.gov/products/intraseasonal/z500_sh_anim.
shtml

Sea Surface temperature anomalies as at 30 May
from psl.noaa.gov/map/clim/sst.shtml

The Galapagos area is now showing warm anomalies.

There is a cold anomaly along the Canadian east coast

Also stronger upwelling and cold water off Baja California.

The Kuroshio current is warmer than normal..

From http://www.psl.noaa.gov/map/images/fnl/slp_30b.fnl.html

During May the main changes have been season.  The Sub tropical ridge
in southern hemisphere has weakened. The heat low over Asia has
intensified and pressures have risen over Siberia.

Pressure anomalies for past month (below)

Shows the reversal of those anomalous  April lows in Tasman Sea and
mid-South Atlantic,.


The 1020 isobar has shifted northwards .

TROPICS

The latest cyclone activity report is at zoom.earth and
tropic.ssec.wisc.edu and Tropical Cyclone Potential is
from http://www.ospo.noaa.gov/products/ocean/tropical/tcfp/

A quiet time for tropical cyclones. Tropical Storm Alvin, the first
named storm of the eastern North Pacific hurricane season, formed off
the coast of southern Mexico.

WEATHER ZONES

Rain accumulation this week from Windy.com shows well defined SPCZ
between Solomon Islands and Samoa.  Also a passing trough near French
Polynesia.

Wind and rain accumulation this week from Windy.com

The wind accumulation shows a small squash zone ner Southern Cooks on
north side of a traveling High mainly on 4 and 5 June. Also bands of
strong winds off east of NZ around a deep low mainly after Wednesday.
 

LOWS and HIGHS

HIGH H1 has been crossing by north of NZ today and is expected to
travell east along 30 to 35S stalling south of French Polynesia late
in the week

 Low L1, is expected top form off Queensland coast on Monday and
deepen crossing NZ on Thursday and Friday then lingering east of NZ at
end of the week with a southerly flow over NZ.

HIGH H2 in Aussie bight should move NE across New South Wales on
Thursday and weaken in the northern Tasman Sea by end of the week.

LowlL2 should follow H2, reaching New South Wales at end of the week.

Gulf of Panama:   SW 10kt becoming light winds after Thursday, but
oulook next week  is for SW up to 20kt .

6N to 2N: Showery, often westerly or SW winds and a sea drifting to
east

2N to Galapagos: Winds from between SE and S and a sea drifting to the
NW/west

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 

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.

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