Scientific Forecaster Discussion
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Area forecast discussion
National Weather Service San Francisco Bay area
255 am PDT Thursday Apr 24 2014
Synopsis...a storm system will bring cooler temperatures and
chances for precipitation to the region late Thursday night
through Friday. Another weaker system could bring rain chances to
northern California Saturday night and Sunday. Then high pressure
will bring dry and significantly warmer conditions to the area
Discussion...as of 2:55 am PDT Thursday...satellite imagery shows
some low clouds over the coastal waters and extending into portions
of Marin and Sonoma counties. High clouds are starting to enter
into northern Sonoma County as well. Temperatures and dew points
are running higher than yesterday at this time. With this head
start...as well as weakening high pressure remaining over the area
..another mild day is on tap for the district with highs expected
in the 60s and 70s.
An upper trough off the Pacific northwest will drop southeast
into northern California tonight bringing a chance of rain to the
North Bay late tonight and into the rest of the district Friday.
The upper low center is still forecast to move across central
California late Friday thus thunderstorm chances are still
warranted. The trough is forecast to move quickly eastward with
showers ending by Saturday morning. Another weaker system is
forecast to move across late Saturday night into Sunday...but
rain chances are expected to remain from about the Bay area north.
High pressure is then prognosticated to build in strongly over the
eastern Pacific and onto the coast. This will bring in dry weather
and warmer temperatures through the rest of the work week. Highs
by Tuesday and Wednesday could push into the 90s across the
warmest inland sections of the district.
Aviation...as of 10:55 PM PDT Wednesday...patchy stratus is
beginning to form along the northern and central coast. Stratus
has not been as aggressive as earlier anticipated therefore have
pushed stratus onset back a few hours. Increasing high clouds are
expected to continue as an approaching cold front nears the West
Coast. West winds will continue to ease as the night progresses.
Vicinity of ksfo...VFR conditions expected through late tonight.
Will bring MVFR 11z over ksfo and 12z over koak. West winds
will continue to ease as the night progresses.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR conditions expected through
tonight with MVFR ceilings expected tomorrow morning. Light winds
expected through the night.
Marine...as of 05:00 PM PDT Wednesday...west and northwest winds
will prevail along the central coast into the weekend. Winds will
be locally stronger along the coast...especially south of Point
Sur tonight and Thursday. A long period south swell entering the
coastal waters Friday night/early Saturday. Initially 2-3ft with a
period of 20 second...then 2-4ft with a period of 18-19 second on Saturday. The
south swell may get mixed out a little bit with a moderate northwest wind
and moderate northwest swell.
... Pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 10-60 nm
Small Craft Advisory...Monterey Bay from 2 PM
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm from 2 PM
Public forecast: Sims
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