Scientific Forecaster Discussion
fxus66 kmtr 171133
Area forecast discussion
National Weather Service San Francisco Bay area
333 am PST Fri Nov 17 2017
Synopsis...a few residual showers will taper off from north to
south overnight and end this morning. Dry and cooler weather is
forecast for today and through the weekend. The next system will
bring renewed chances of rain beginning late Sunday night into
Discussion...as of 3:21 am PST Friday...latest radar scans show
some residual shower activity occurring from the Monterey Bay
south, all moving to the east as the frontal system departs the
district. During the past 3 hours, anywhere from a few hundredths
to nearly a half inch fell in Santa Clara, Contra Costa, Alameda,
San Mateo and Monterey counties. Expect this activity to wrap up
shortly after sunrise with the rest of the day being dry and cool.
Highs today are forecast to be in the upper 50s to mid 60s. Lows
tonight will be considerably cooler under clear skies, with 30s to
mid 40s expected.
Weak ridging over California will keep dry conditions across the
state for much of the weekend. Another storm system is due to
approach the area late Sunday bringing rain chances to mainly the
San Francisco Bay area northward Sunday night into early Monday,
although rain could reach as far south as the Monterey Bay by
mid-morning Monday. Another system is then slated to arrive after
midweek. Difference in model solutions continue, so confidence
remains low concerning precip amounts or even timing and areal
Aviation...as of 3:30 am PST Friday...satellite image shows
lower based clouds associated with the front have moved out of the
sfo Bay area. The trailing end has yet to move out of the mry Bay
area but it is expected to clear around midmorning. Clear skies
at sts has resulted in the development of radiational fog.
Surface high pressure building into the southern Oregon coast will
provide a dry northerly flow over the area tonight which will
bring VFR conditions.
Vicinity of ksfo...VFR as lower clouds move out of the area.
Sfo bridge approach...similar to ksfo.
Monterey Bay terminals...MVFR cigs with some rain showers through
Marine...as of 3:00 am PST Friday...high pressure will build
into southern Oregon this afternoon resulting in light northerly
winds through Saturday. Locally stronger winds are possible along
the Big Sur coast in the afternoons and evenings due to the
coastal jet. Winds will switch to northwest Saturday night then
southerly Sunday as the next storm system approaches northern
... Pinos to pt Piedras Blancas 0-10 nm from 12 PM
Public forecast: Sims
aviation: west pi
marine: west pi
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