Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
1030 am PDT Friday Aug 22 2014
Synopsis...night and morning low clouds and slightly below
normal afternoon high temperatures are forecast through the
weekend. Warmer temperatures are possible inland by the middle of
Discussion...as of 9:00 am PDT Friday...interesting satellite loop
this morning with a good portion of sf Bay clearing out early
while all of Monterey Bay down into most of the Salinas valley
remains cloudy mainly due to a northwest flow at the surface. Fort Ord
profiler indicates the marine layer around 1500 feet. After clouds
clear look for highs back into the 60s and lower 70s at the coast
with middle 70s to middle 80s inland.
Overall looks quiet through the weekend with westerly flow at the
surface expected to continue. This will lead to typical gusts
along gaps and into the Delta all afternoon and early evening
hours. Temperatures will only vary by a few degrees each day.
Only item of note is the model continue to bring a NE wind to the
North Bay mountains Saturday morning and afternoon with gusts to
15 miles per hour. Although it will not meet red flag criteria, there are
elevated fire weather concerns for that area.
Previous discussion...upper level ridge brought temperatures
back to near normal Thursday. The marine layer has compressed to
around 1500 feet per the feet Ord profiler. The marine layer has
become shallow enough that drizzle is not expected this morning.
An upper level trough is currently deepening over the Pacific
northwest. This will increase the onshore flow and deepen the
marine layer resulting in slightly cooler temperatures today. The upper
level trough will move into the Great Basin Friday but a secondary
upper trough will move through the Pacific northwest which will
keep temperatures slightly below normal through the weekend. The
marine layer may become deep enough to produce local drizzle along
the coast and coastal hills tonight and early Saturday.
Medium range models continue to show an upper level ridge over the
eastern Pacific moving over California by Tuesday. Temperatures
will start to warm on Monday then warm up more significantly
Tuesday and Wednesday with widespread 90s over the inland areas.
The marine layer will become shallower and cooling will be
confined to the immediate coast.
Aviation...as of 10:30 am PDT Friday...morning stratus is
starting to clear back to the coast. Look for afternoon seabreeze
winds and low clouds spreading back inland overnight.
Vicinity of ksfo...VFR today. Low clouds reforming after midnight. The
seabreeze will reach 15 to 20 knots this afternoon.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR. Low clouds reforming during the
evening. Seabreeze winds expected to reach 10 to 15 knots this
Marine...as of 10:22 am PDT Friday...generally light to moderate
winds will continue across the coastal waters through much of the
forecast period. Strongest winds expected over the northern outer
waters. A moderate period southerly swell...generated by tropical
storms will move into the region and continue into early next
... Arena to pt Reyes 10-60 nm
Small Craft Advisory...sf Bay north of the Bay Bridge from noon
Small Craft Advisory...sf Bay south of the Bay Bridge from 2 PM
Public forecast: Bell/west pi
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