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Area forecast discussion 
National Weather Service San Francisco Bay area
424 am PDT Sat Jul 30 2016

Synopsis...typical summertime conditions will continue over the
next several days with low clouds/fog and cool temperatures near
the coast along with warm conditions inland. Look for a gradual
cooling trend for inland areas through Monday as an upper level
trough develops across the Pacific northwest and northern
California. Smokey conditions will continue over portions of the
Monterey Bay area northward into the South Bay.

&&

Discussion...as of 3:15 am PDT Saturday...as expected clouds
have returned to all coastal regions this morning along with most
adjacent valley spots. 24 hour change products indicate only minor
difference from early Friday morning with the marine layer still
around 1000 feet and the onshore flow around 3 mb. Satellite heat
product shows the soberanes fire in Monterey County near Big Sur.

An approaching longwave trough will advance southward down the
coast today. This will lead to slightly cooler conditions
especially for inland locations. A secondary feature will then
rotate along the trough for Sunday into Monday which will lead to
additional inland cooling. By Monday inland highs will mostly be
in the 80s to lower 90s with higher temperatures confined to San
Benito and Monterey counties. Coastal locations will see only
minor day-today variations.

As the previous shift mentioned, some of the models are hinting
that mid-level moisture could move into our County Warning Area on Monday from the
southeast. The latest run of the NAM has backed off a bit from
that suggestion, although a small pocket of moderate moist air and
instability GOES through southern Monterey County. The other
models are less bullish and keep the moist air farther to the
south.

Temperatures will be near normal through the remainder of the
week as the longwave trof moves across our area and remains fairly
stationary. No precipitation is expected.

&&

Aviation...as of 4:30 am PDT Saturday...a developing surface low
off the coast will bring a light south to southwest flow to the
area today. Marine layer is holding steady near 1000 feet and
clouds have spread into the east side of the sfo Bay area. IFR cigs
now reported at Oak and smb. Southerly flow should keep stratus
mostly out of sfo but the approach will be impacted from the smb
south. Marine layer is shallow enough for clearing to take place
around 17z.

Vicinity of ksfo...mostly VFR but some clouds from the south may
cause tempo IFR cigs between 14z-17z.

Sfo bridge approach...IFR cigs through 17z.

Monterey Bay terminals...IFR/LIFR through 17z.

&&

Marine...as of 4:30 am PDT Saturday...high pressure off the
northern California coast will keep moderate northwest winds over
the northern outer waters. A weak surface low will develop near
shore resulting in light southerly winds.

&&

Mtr watches/warnings/advisories...
... Arena to Pigeon pt 10-60 nm
Small Craft Advisory...sf Bay from 2 PM

&&

$$

Public forecast: Bell
aviation: west pi
marine: west pi



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