Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
929 am PST Friday Nov 27 2015
Synopsis...dry and cool weather can be expected through the
weekend. Temperatures will begin to moderate early next week.
There is also a chance of rain beginning late next week.
Discussion...as of 8:57 am PST Friday...the upper level low over
Nevada continues to spread a dry and cold airmass over the area
with offshore flow from the north to northeast. Overnight...offshore
winds persisted in the North Bay and parts of the sfo Bay area
which kept temperatures above freezing. Lighter winds across the
southern third of the district allowed overnight minimums to drop
into the upper 20s and 30s...so the freeze warnings and frost
advisories mostly verified in southern zones. Current temperatures
are ranging from the middle 30s to the upper 40s...warmest in the
The upper low will remain nearly stationary through Saturday
before moving east on Sunday. Clear and cool weather is expected
today with highs in the 50s. Winds will likely hold up through
Saturday morning before decreasing Saturday night. Minimum
temperature forecast will be tricky again tonight depending on the
winds. Minimum temperatures Saturday night may be colder if the
winds decrease as forecast.
An upper level ridge moves over the West Coast Sunday. The flow
will become more westerly and temperatures will start to moderate.
A weak system will dissipate as it approaches the ridge but it
could still bring a slight chance of showers to the area late
Monday or Tuesday. Another system could possibly bring a better a
chance of rain to the area next Thursday or Friday.
Aviation...as of 9:40 am PST Friday... widespread VFR through taf
period. Little change in the synoptic pattern over the last 24
hours with upper low resting over Great Basin. Dry offshore flow
has dominated the last 24 hours and will continue to do over the
next 24 hours as thermal trough remains just offshore.
Vicinity of ksfo...VFR.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR.
Marine...as of 8:35 am PST Friday...light winds and seas will
persist through the weekend. Winds and seas are expected to
increase beginning early next week as a weak frontal system moves
into the California coastal waters.
Public forecast: Sims
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