Scientific Forecaster Discussion

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Area forecast discussion 
National Weather Service San Francisco Bay area
450 PM PDT Friday Apr 18 2014

Synopsis...dry conditions and near seasonal daytime temperatures
will persist through the weekend. Overnight and early morning low
clouds and patchy fog will also be possible during the next
several days. An upper level low pressure system will then
approach the region late Monday and Tuesday bringing a chance
of showers as well as cooler temperatures through Wednesday.

&&

Discussion...as of 2:33 PM PDT Friday...low clouds are still
stubborn to clear from the western portion of the San Francisco
peninsula as well as near Monterey. The rest of the district...
however...is enjoying nice sunshine with afternoon temperatures in
the 60s and 70s so far. The weekend is expected to be similar as
high pressure builds in over the west. Night and morning coastal
stratus can be expected this weekend along with mild temperatures.
Sunday is expected to be the warmest day with inland readings
topping out in the middle to upper 80s.

An upper level trough is still forecast to affect California next
week. It is prognosticated to approach the West Coast late Monday...and move
through the region Monday night through Tuesday evening. This
system could bring rain chances to most areas late Monday through
Tuesday. The greatest chances for rain will be across the North
Bay where the best upper level support and moisture will be...but
precipitation could reach as far south as portions of southern
Monterey County.

As this system moves eastward on Wednesday...rain chances will
diminish and temperatures will warm slightly through the latter part
of the work week. The medium range models are coming into better
agreement regarding the possibility for rain next weekend. They
are all trending towards a stronger and wetter Pacific storm
system impacting the region next weekend. Keeping fingers crossed.

&&

Aviation...as of 4:50 PM PDT Friday...the current visible
satellite image is showing mostly clear skies from roughly Santa
Cruz north with overcast skies engulfing southern Monterey Bay and
pushing into the Salinas valley. The Bay area sodars really are
not showing a definitive marine layer. With this in mind I don't
expect an early return of stratus if it returns at all to the Bay
area it will be late. One the other hand the marine layer is a
solid 2000 feet deep on The Fort Ord profiler and stratus is
showing no signs of clearing anytime soon in Monterey.

Vicinity of ksfo...VFR is expected to persist through the next 24
to 36 hours. Patchy stratus may develop to the north and east of
the terminal late tonight. West winds 20 knots gusting to 27 knots will
subside to around 10 knots later this evening.

Moderate confidence.

Ksfo bridge approach...similar to ksfo with stratus possible late
tonight east of the approach.

Moderate confidence

Monterey Bay area terminals...MVFR ceilings are expected to prevail
through 1200z tonight at which ceilings will fall to around ovc007.
Ceilings will improve to ovc015 by 1700z Saturday morning. West
southwest winds 10 to 12 knots will diminish to around 5 knots this
evening.

High confidence.

&&

Marine...as of 12:45 PM PDT Friday...small craft advisories continue
across all Pacific waters and Monterey Bay with northwest winds of
20-30 kts. Winds will gradually diminish overnight from north to S and
will continue with Small Craft Advisory in southern waters through late Saturday
morning due to moderate northwest winds. Increasing confidence in
arrival of large northwest swell on Sunday to produce hazardous beach
conditions from elevated rip current threat. Will monitor
conditions for possible issuance of beach hazard statement as
event approaches.

&&

Mtr watches/warnings/advisories...
... Bay until 11 PM
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm until 11 PM
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm until 11 PM
Small Craft Advisory...Pigeon pt to pt pinos 10-60 nm until 11 PM
Small Craft Advisory...pt Arena to pt Reyes 0-10 nm until 3 am
Small Craft Advisory...pt Arena to pt Reyes 10-60 nm until 3 am
Small Craft Advisory...pt Reyes to Pigeon pt 10-60 nm until 3 am
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 10-60 nm

&&

$$

Public forecast: Sims
aviation: Larry
marine: Johnson

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