Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
432 am PDT Wednesday Oct 22 2014
Synopsis...dry weather conditions and seasonable temperatures will
persist through today with precipitation possibly returning to the
North Bay on Thursday. Rain chances will then increase and spread
southward Friday night into Saturday as an upper level system
moves across northern California.
Discussion...as of 2:58 am PDT Wednesday...aside from some high
clouds moving across the area...skies are mostly clear. Current
temperatures are ranging from the middle 60s to the lower 50s. Mostly
sunny skies are expected today with increasing clouds from the
north during the afternoon. Highs today are expected to be similar
to those on Tuesday...perhaps a few degrees cooler across the
north with increasing clouds. Highs are expected to be in the 60s
and 70s across the board.
A short wave trough associated with a long-wave upper level trough
over the Gulf of Alaska will approach the northern California
coast and begin to affect our area late tonight with increasing
clouds and a slight chance of precipitation across the North Bay by early
Thursday morning. Chances of rain will increase and spread south
during the day Thursday and persist into Friday. Shower chances
will continue into the weekend...then gradually taper off. Drier weather
may return as soon as Sunday and dry weather is expected on Monday
and possibly Tuesday. Medium range model solutions differ
regarding how much the upper ridge builds in and how low precipitation
will be held off. The GFS and Gem models both bring precipitation to the
area on Tuesday...however the European model (ecmwf) keeps the area dry through the
middle of next week. Thus...low confidence out in the extended
Aviation...as of 04:30 am PDT Wednesday...VFR with only high
cirrus clouds and mostly light winds through at least late
afternoon across the area. A front approaching the area tonight
should increase low level cloud cover tonight. Light rain is
possible at sts just beyond the forecast period late tonight.
Vicinity of ksfo...VFR today. Light winds through the morning with
a light to moderate sea breeze this afternoon. Stratus possible
Ksfo bridge approach...similar as ksfo.
Monterey Bay area terminals...VFR through afternoon. Mostly light
winds. Patchy stratus to develop late evening.
Marine...as of 2:29 am PDT Wednesday...moderate northwest winds
continue over the coastal waters south of Point Sur through
tonight. Elsewhere winds remain mostly light. Northwest swell will
continue to gradually decrease through the end of the week.
... Pinos to pt Piedras Blancas 0-10 nm
Public forecast: Sims
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