Scientific Forecaster Discussion

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Area forecast discussion 
National Weather Service San Francisco Bay area
845 am 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 8:45 am PDT Friday...satellite imagery is
showing a lot less cloudiness across the district this morning as
compared to 24 hours ago. Currently with a very shallow marine
layer...stratus clouds are hugging the coastline and extending
only locally inland over the Monterey Bay area and along the San
Mateo coast. Expect a warmer day today across much of the area but
especially across the southern third of the district mainly due to
the additional sunshine expected today. Highs today should be in
the 60s and 70s...but there could be some lower 80s in portions of
San Benito County and across the interior sections of southern
Monterey County. 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.

Forecast models continue to advertise an upper level trough
prognosticated to approach the West Coast late Monday. This system is is
slated to move through the region Monday night through Tuesday
evening bringing chances for rain showers across 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 warm slightly through the latter part of
the work week. The medium range forecast models are hinting at the
possibility of a stronger and wetter Pacific storm system
impacting the region next weekend.

&&

Aviation...as of 4:45 am PDT Friday...patchy stratus this morning
mostly confined to the immediate coast plus a patch in the East
Bay. Marine layer is ill-defined around 1000 feet which should keep
coverage limited despite onshore gradient. Ceilings to dissipate by
middle morning except at the coast. Moderate onshore winds again today.

Vicinity of ksfo...VFR except possible stratus between 13 and 16z.
West winds all day...increasing to around 20 knots with gusts to 30
knots again today.

Ksfo bridge approach...similar to ksfo.

Monterey Bay area terminals...limited clearing at mry as onshore
flow maintains stratus. Patchy ceilings at sns to break out middle
morning...medium confidence.

&&

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

&&

$$

Public forecast: Sims
aviation: ac

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