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Area forecast discussion 
National Weather Service San Francisco Bay area
504 am PDT Wednesday Oct 1 2014

Synopsis...breezy offshore winds in the hills this morning will
ease by midday. Under sunny skies expect much warmer temperatures
this afternoon with highs into the 80s and lower 90s for most of
the Bay area. Warm to hot weather will continue Thursday and
through the weekend with strong high pressure centered over
California. Some subtle cooling will return by early next week as
onshore flow returns ahead of the next upper trough.

&&

Discussion...as of 3:24 am PDT Wednesday...looks like the coast is
clear. The northerly gradient is 6 mb down the coast and about 7 mb
from sfo-wmc...setting the stage for a classic early fall offshore
wind event and associated warming trend across the Bay area. So
far some of the of the strongest wind gusts have been 47 miles per hour on Montana
Diablo...38 miles per hour at Knoxville creek and 27 miles per hour on Montana Tamalpais. At
this time the strongest winds are generally staying above 2000
feet but the last report out of Oakland North at 1400 feet had a
gust to 33 miles per hour. As the sun comes up some of the winds will mix
down as the morning inversion breaks. The strongest winds will end
by lunchtime followed by a sunny and warm to hot afternoon across
the district as light offshore flow continues through this
afternoon and into tonight.

A very dry airmass will spread over the region tonight with
persistent but light offshore flow. Expect very poor humidity
recovery which will be a fire weather concern. In general
overnight lows will stay fairly mild in the 50s and lower 60s. The
persistent north winds over the ocean has finally allowed some
upwelling to occur with buoy 14 showing a 3 degree SST drop in the
last 24 hours...this will allow at least a few degrees more of
cooling near the coast as were already seeing 54 in Monterey which
is closer to normal instead of the 60 degree readings we've seen of late.

Anyway the strong high will really take hold Thursday and Friday
with a 594 dm high centered over Southern California but the 592
dm line passing through the Bay area. This in combination with
light offshore or neutral gradients will allow for widespread 80
and 90 degree readings across the district. Heat sensitive
populations should take extra precautions with fire weather
concerns remaining elevated as well. At this time Friday still
looks to be the hottest day but were really splitting hairs in
that both Thursday and Saturday look similarly warm to hot as well.

Any cooling of note will likely hold off until about Monday of
next week as onshore winds return...at least close to the coast.

&&

Aviation...as of 5:00 am PDT Wednesday...dry offshore flow over
the area.

Vicinity of ksfo...VFR.

Ksfo bridge approach...VFR.

Monterey Bay area terminals...VFR.

&&

Climate...record high temperatures for Wednesday through Friday
(10/1 to 10/3) along with the most recent date it occurred.

Sf Bay area
location.................10/1...........10/2............10/3...
Kentfield................97/2012.......100/2012.........99/2012
San Rafael..............104/1980.......106/1980........105/1980
Napa....................106/1980.......102/1980........103/1917
San Francisco............97/1980........96/1980.........97/1985
sfo Airport..............97/1980........96/1980.........94/1985
Oakland (downtown)......103/1980.......103/1980........100/1985
Oakland Airport..........94/1952........98/1980.........95/1985
Richmond.................99/1980.......100/1980.........97/2012
Livermore...............102/1952.......106/1980........106/1980
Moffett field............93/1980........95/2012.........97/1985
San Jose.................97/1980........96/2012.........97/1985
Gilroy..................104/2001.......107/1980........106/1980

Monterey Bay area
location.................10/1...........10/2............10/3...
Monterey................103/1980.......101/1980.........96/1985
Santa Cruz..............102/1965.......102/1980........102/1980
Salinas.................104/1980.......100/1980.........97/1985
Salinas Airport.........105/1980.......103/1980.........99/1985
King City...............109/1980.......107/1980........102/1980

&&

Marine...as of 8:13 PM PDT Tuesday...moderate northwest winds
will continue over the coastal waters through tomorrow. Winds
become light Wednesday night through the rest of the week as high
pressure builds over the Great Basin.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 10-60 nm
Small Craft Advisory...pt Reyes to Pigeon pt 10-60 nm until 9 am
Small Craft Advisory...Pigeon pt to pt pinos 10-60 nm until 9 am
Small Craft Advisory...pt pinos to pt Piedras Blancas 10-60 nm until 9 am

&&

$$

Public forecast: rww
aviation: west pi
marine: Sims
climate: Bell

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