Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
308 am PDT Wednesday Jul 23 2014
Synopsis...a gradual warming trend is expected to begin on
Thursday and continue into the upcoming weekend as high pressure
builds over the region.
Discussion...as of 3:00 am PDT Wednesday...after an active day
yesterday, a much quieter start to the day today. Satellite
currently shows a couple of small bands of high clouds drifting
across while closer to the surface the satellite and observation show a
mix of clouds and clear skies. Main stratus deck is well off the
northern coast right now and should be limited to the northern
third of our County Warning Area today. That will allow areas to the south to
quickly warm today as the Main Ridge of high pressure to the east
starts to build back into our County Warning Area. Highs will be in the 60s and
70s at the coast with middle 70s to upper 80s for most inland spots.
Temperatures will continue to warm through the rest of the week as the
ridge continues to expand into California while 850 mb temperatures
increase from 14-16c to 21-24c over the weekend. Sea breeze will
be very limited as a ridge at the surface attempts to build to
the north. Highs will increase to the upper 60s to lower 80s at
the coast with 80s and 90s inland. Far interior spots could top
100. In other words, look for a typical period of warm late July
weather. Models are also hinting at the return of some subtropical
moisture over the weekend from the south -- modified total totals
off the GFS are over 30 in parts of Monterey County on Sunday.
Will hold off any mention of showers or thunder until newer runs
of the NAM come in that go through the entire weekend.
Longer range guidance through next week keeps warmer than normal
weather through our area. Showers at this time look unlikely as
the ridge settles over the SW Continental U.S. And effectively blocks any
moisture from the south moving into our area. Confidence is high
through next week (cpc 6-10 day forecast gets a 5 out of 5 for
confidence placing it well above normal).
Finally, Worth noting that the Monterey Bay buoy set a record for
a water temperature of 67 degrees on Tuesday.
Aviation...as of 10:15 PM PDT Tuesday...residual surface humidity
and weak low level instability resulted in some strato-cumulus cloud
development over the Bay area late this afternoon. The clouds have
dissipated over the central coast but have held together over the
Bay area for the time being. It's much drier aloft according to the
00z Oakland upper air sounding.
Vicinity of ksfo...low cloud cover persisted a little longer through
the evening but is seemingly scattering out at this time. VFR is
forecast for the period.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...patches of low clouds are likely to
Marine...as of 02:15 PM PDT Tuesday...light winds over the coastal
waters will continue through tomorrow morning due to a weak
pressure gradient. Tomorrow afternoon northwest winds increase as
high pressure strengthens over the eastern North Pacific.
... Bay from 3 PM
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm from 3 PM
Small Craft Advisory...pt Arena to pt Reyes 10-60 nm from 6 PM
Small Craft Advisory...pt Reyes to Pigeon pt 10-60 nm from 6 PM
Small Craft Advisory...Pigeon pt to pt pinos 10-60 nm from 6 PM
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm from noon
Small Craft Advisory...pt Arena to pt Reyes 0-10 nm from 3 PM
Small Craft Advisory...pt pinos to pt Piedras Blancas 10-60 nm from 3 PM
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm from 6 PM
Small Craft Advisory...sf Bay north of the Bay Bridge from noon
Public forecast: Bell
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