Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
1049 am PDT Sat may 30 2015
Synopsis...seasonable weather today with temperatures 60s
coast...70s around the Bay and some 80s well inland. As the marine
layer Burns off today high clouds will be on the increase ahead of
an incoming weather system. Slight cooling trend on Sunday as the
system stays off the coast and brings only a slight chance of
showers to the far North Bay. Zonal flow Monday through most of
next week will keep temperatures on the cool side of normal with
dry weather and widespread night and morning stratus.
Discussion...as of 9:21 am PDT Saturday...the marine layer has
ramped back up and is now around 2000 feet deep per output from
The Fort Ord profiler. Satellite imagery shows about the same
amount of low cloudiness filling inland valleys as yesterday at
this time...as well as high clouds moving across most of northern
California. Current temperature trends are running similarly to
yesterday at this time with readings in the 50s. Expect low clouds
to clear to the coast by late this morning...and highs today are
forecast to range from the 80s inland...to the 60s and 70s at the
coast and bays.
An approaching upper level trough will bring cooler temperatures
to the area on Sunday as well as a slight chance of light rain
across the northern zones late Sunday evening and overnight. The
main effect will be an increase of the afternoon sea breeze that
will cool things off even well inland. The zonal flow aloft will
maintain into next week resulting in temperatures near or slightly
below normal. Other than coastal drizzle the forecast remains dry
in the long range.
Aviation...as of 10:48 am PDT Saturday...the current visible
satellite image is showing stratus in San Francisco Bay...the
North Bay valleys and along the immediate coastline. Stratus is
clearing rapidly around the area and most terminals should be VFR
shortly. The Fort Ord profiler is showing a 1000 foot deep marine
layer which will promote a return of low clouds and drizzle to the
coast once again this evening.
Vicinity of ksfo...IFR ceilings are expected to scatter out within the
next hour or so providing VFR conditions through this afternoon.
IFR conditions will return this evening. West winds are expected
to increase to 20 knots this afternoon with gusts to 26 knots.
Confidence is moderate.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...stratus continues to linger along
the coast but VFR conditions are present at ksns. Currently it is
VFR at kmry but MVFR ceiling bkn015 have been moving in and
out...VFR should prevail by 2000z. Westerly winds will reach 10 knots
this afternoon. Stratus is anticipated to return by the early
Confidence is moderate at kmry.
Confidence is high at ksns.
Marine...as of 8:39 am PDT Saturday...generally light
northwesterly winds will prevail today. Winds are anticipated to
remain generally light and become southerly on Sunday as a low
pressure system approaches the coast. Seas will also remain gentle
through the first of the week. The surface pressure gradient is
expected to strengthen midweek resulting in increasing northwest
winds and building seas.
... Bay north of the Bay Bridge from 2 PM
Small Craft Advisory...sf Bay south of the Bay Bridge from 2 PM
Public forecast: Sims
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