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Area forecast discussion 
National Weather Service San Francisco Bay area
459 PM PDT sun may 24 2015

Synopsis...after a couple more cooler than normal days temperatures
are expected to climb above normal especially for inland areas
toward the end of the week. However...coastal areas will remain
seasonably cool as onshore flow persists.

&&

Discussion...as of 3:00 PM PDT Sunday...after a very promising
start to the day with a shallower marine layer and fewer
clouds...sunshine has not been able to make it to most coastal
spots. Surface analysis shows westerly gradients now over 4 mb
which is combining with sea surface temperatures of 53 to 55 degrees to
greatly overpower clearing to the coast. Temperatures are running
close to yesterday with a few inland spots as much as 4 degrees
ahead while at the coast most places are the same or slightly
cooler. Downtown San Francisco is standing at 55 right now which
is around 20 degrees cooler than the forecast high for Fairbanks
Alaska. Clouds should return for all spots tonight for elevations
under 2500 feet. Lows will likely be about the same as they were
this morning,,,upper 40s to upper 50s. Monday and Tuesday although
a slightly weaker west to east gradient plus more compressed
marine layer should help to bring a small reduction in the clouds
during the afternoon.

A ridge of high pressure to our west will build into our County Warning Area
starting on Wednesday and become the dominate feature in our
weather at least through the upcoming weekend. At the same time
850 mb temperatures will rise as much as 8c which will lead to a return
to warmer than normal temperatures for inland spots. Coastal areas will
see some warming although without an offshore wind setup or
thermal trough off the coast...highs will likely struggle to get out
of the 60s for many of the beaches. Would expect some inland
locations to be well into the 80s by Friday with even lower 90s
not out of the question in portions of Monterey County. After a
chilly may...June will start out on a warm note.

No sign of organized rain for at least the next 10 days.
&&

Aviation...as of 4:58 PM PDT Sunday...for 00z tafs. Overcast
conditions will prevail across ksfo and koak as well as Monterey
Bay area terminals through the period. Stratus will return
overnight across the rest of the area with stratus pushing back to
the coast by noon Monday. Moderate onshore flow will continue
through late this evening with slightly lighter winds anticipated
overnight.

Vicinity of ksfo...MVFR ceilings will persist through the period with
IFR ceilings possible overnight. Moderate onshore flow will prevail.

Ksfo bridge approach...MVFR ceilings will back into the Bay this
evening with ceilings lowering to around 1000 feet overnight. Ceilings
will clear from the south Monday morning but hand on over area
terminals.

Monterey Bay area terminals...mfr ceilings will persist through the
period with IFR ceilings possible overnight. Moderate onshore flow
will prevail.

&&

Marine...as of 3:00 PM PDT Sunday...northwest winds will continue
tonight across the ocean waters with a moderate sea breeze into the
bays this evening. Winds will ease on Memorial Day into Tuesday
with fairly light seas. Some slightly stronger northwest winds will
return by late in the week but in general expect a prolonged
period of generally light wind and seas.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 10-60 nm
Small Craft Advisory...sf Bay north of the Bay Bridge until 9 PM
Small Craft Advisory...pt Arena to pt Reyes 0-10 nm until 9 PM
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm until 9 PM

&&

$$

Public forecast: Bell
aviation: CW
marine: rww

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