Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
248 PM PDT Thursday Sep 3 2015
Synopsis...dry weather will continue through next week.
Cooler temperatures will continue through Friday as an upper
level trough digs southward from the Pacific northwest. A warming
trend will begin over the weekend with warm temperatures
persisting through next week.
Discussion...as of 2:48 PM PDT Thursday...skies have cleared
over all areas except for right around Half Moon Bay. Current
temperature trends are running cooler than yesterday at most
locations by several degrees with readings in the 60s and 70s.
Expect only patchy fog and low clouds overnight...mainly near the
The upper level trough currently aligned along the West Coast will
keep cool conditions over the district through Friday. By Saturday
the trough will begin to move to the east as a ridge of high
pressure currently over the eastern Pacific begins to edge towards
California. This will usher in a warming trend that is expected to
last through the weekend and into early next week. Temperatures
are forecast to be from 5-15 degrees warmer by Sunday and Monday.
Latest runs of the medium range models keep the upper ridge over
the west well into next week...thus highs are expected to stay
warm through Thursday at least. Conditions will remain dry
through the period.
Aviation...as of 11:05 am PDT Thursday... satellite imagery shows
mostly clear skies inland with a few lingering clouds along the
Santa Cruz and Monterey coastlines. Moderate to strong onshore
winds are forecast to increase by this afternoon with sustained
speeds along the coast up to 20kt with gusts locally up to 30kt.
Fort Ord profiler shows a rather mixed our marine layer... and
tonights situation looks a little murky. Forecast leaning towards
persistence with slight modifications for tonight. As such...
shallow marine layer with late arrival/early mixout for tomorrow
morning with MVFR ceilings 1000 to 2000 feet. Confidence for tonight...
low to moderate.
Vicinity of ksfo...VFR today. Breezy onshore winds with gusts up
to 20kt and gusts to upper 20kt. MVFR ceilings posbl between 08-16z Friday.
Strong onshore winds for tomorrow afternoon as well.
Confidence... moderate to high.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR. Winds will strengthen this
afternoon to around 10-15 knots with gust to 20 knots. Hints marine
layer will push into Salinas valley before Monterey tonight.
Lowering MVFR ceilings vary by location... check taf.
Confidence... low to moderate.
Marine...as of 01:47 PM PDT Thursday...northwest winds increase
over the coastal waters today as a trough deepens into the region.
Moderate to strong winds will persist into tomorrow before
decreasing this weekend. Areas with the strongest winds could see
hazardous conditions from steep fresh swell. A long period
southerly swell moves into the region late in the weekend.
... Bay from 2 PM
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm from 2 PM
Small Craft Advisory...pt Arena to pt Reyes 0-10 nm
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm
Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Public forecast: Sims
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