Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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FXUS66 KMTR 290400

Area Forecast Discussion
National Weather Service San Francisco Bay Area
900 PM PDT SAT MAY 28 2016

.SYNOPSIS...Dry weather is forecast through the Memorial Day
weekend and through the end of next week. Slight cooling will
occur on Sunday, mainly near the coast. A warming trend is then
expected on Memorial Day and Tuesday. Temperatures are then
expected to remain above normal through the end of next week.


.DISCUSSION...As of 9:00 PM PDT Saturday...Saturday was a warm
day with afternoon highs anywhere from 5 to 15 degrees above
normal. Fog was present along the coast from the Monterey
Peninsula southward, but otherwise most areas experienced sunny
conditions. A weak upper trough moving inland across central and
southern California triggered widespread afternoon and early
evening thunderstorms over the Sierra Nevada, and also produced an
isolated thunderstorms over far southeastern Monterey County at
about 6 pm this evening.

Fog and low clouds remain confined primarily to the Monterey
County coast this evening. Both the NAM and WRF models indicate
increasing coastal fog and low clouds farther north up the coast
overnight. However, given the current robust 6.6 mb north-to-
south surface pressure gradient from ACV to SFO, it`s not likely
fog will develop much farther north than the Golden Gate overnight,
nor will there likely be much development inland from SF Bay. A
forecast update was recently completed to reduce the amount of
inland low clouds and fog late tonight and Sunday morning,
particularly in the East and South Bay.

The models agree on modest cooling for Sunday as onshore flow
increases. Most significant cooling is expected near the coast
where afternoon highs may be as much as 10 degrees cooler than

An upper level ridge over the Eastern Pacific is forecast to build
across California beginning on Monday...resulting in a warming
trend from Memorial Day into Tuesday. Night and morning fog and
low clouds will become less extensive and confined primarily to
areas near the ocean on these two day as the marine layer

The upper ridge is forecast to shift to our east by the middle of
next week as an upper trough develops offshore. This will likely
result in a pause in the warming trend for a few days...and
perhaps even slight cooling on Wednesday and Thursday. In any
case, temperatures are projected to remain warmer than normal
through the end of the week.

Both the GFS and ECMWF models indicate the potential for isolated
showers or thunderstorms by next weekend as an upper low
approaches the central/southern California coast.

&& of 5:15 PM PDT Saturday...Strong northerly gradient
is keeping stratus from the Mry Bay Area south. This is expected
to weaken tonight allowing stratus into the SFO Bay Area late
tonight well after the airport evening rush.

Vicinity of KSFO...MVFR cigs after 10Z possibly later.
West winds to 18 kt through 04z.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...Stratus has pulled back from the bay so
it will remain vfr for a while longer. Cigs expected to fill in
after sunset with mvfr cigs by 05z.

&& of 2:31 pm PDT Saturday...Gusty northwest winds are
expected to prevail over the waters through the weekend. Winds
will be strongest across the outer coastal waters. These gusty
winds will generate steep fresh swell and choppy sea conditions.
Winds are anticipated to ease beginning early next week with
improving sea conditions. Meanwhile, a building southerly swell is
anticipated to arrive early next week.


     .Tngt...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm




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