Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
335 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 3:30 am PDT Friday...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
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 10:50 PM PDT Thursday...low clouds are filtering
back in through coastal gaps and canyons. Models have back off on
cloud cover over ksfo however do not think it will stay clear all
night. Still anticipating a late return over the sf Bay terminals.
Clearing is expected around 17z Friday morning across area
terminals. Light winds will persist through the night.
Moderate to high confidence.
Vicinity of ksfo...VFR conditions expected through late tonight...
possibly after 10z. Clearing anticipated around 17z Friday
morning. Moderate to high confidence.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...IFR ceilings expected through the night
with clearing anticipated around 17z Friday morning. Moderate to high
Marine...as of 10:33 PM PDT Thursday...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: west pi
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