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000 
FXUS66 KMTR 270542
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1042 PM PDT Thu Apr 26 2018

.SYNOPSIS...An upper low off the coast will keep temperatures 
below normal through the end of the work week and into the 
weekend. Some coastal drizzle or very light showers possible late 
Friday through early Saturday as the upper low moves onshore, 
however most areas will remain dry with below normal temperatures 
being the main impact. Cool and dry pattern will continue into 
early next week.

&&

.DISCUSSION...as of 08:40 PM PDT Thursday...Current satellite
imagery showing stratus beginning to develop along the coast with
the marine layer at around 2500 ft per the Fort Ord Profiler.
Highs around the area this afternoon were mainly in the 60s with
some far inland areas hitting the low 70s. Temperatures were about
5 degrees cooler today than they were yesterday. This cooling
trend will continue tomorrow and through the weekend when 
temperatures will be around 5 to 10 degrees below seasonal normals 
by Saturday.

Expect stratus to make its way inland and down the valleys 
overnight tonight as an upper level low continues to move 
eastward from the Pacific. Not much has changed since the last 
forecast update. The aforementioned low is set to approach the 
California/Oregon boarder towards the end of the work week. This 
will continue to bring in morning low clouds with some possible 
drizzle along the coast. Light rain is possible for parts of the 
North Bay as the system moves onshore Friday night into Saturday 
morning. Any accumulations from this system would be minimal. 

The upper level low will move inland to the northeast by Sunday
and Monday before a weak shortwave trough slides down the coast 
early next week minimizing warming. Temperatures will steadily 
rise mid week as a high amplitude ridge builds over the eastern 
Pacific and gradually moves towards the California coast. 

&&

.AVIATION...As of 10:40 PM PDT Thursday...For 06z TAFS. Marine 
layer has been disrupted by an approaching upper low. However, low
clouds have been slowly increasing through the evening and are 
expected to become widespread overnight. MVFR ceilings forecast to
develop in most areas by 10Z and then clear between 16-19Z 
Friday. 

Vicinity of KSFO...MVFR ceilings forecast to continue through 17Z
Friday. Confidence moderate. Light west winds overnight,
increasing to 15 kt by 22Z Friday.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR ceilings expected to persist until 
18-19Z Friday. Light west to southwest winds. 

&&

.MARINE...as of 8:40 PM PDT Thursday...Generally light west to 
northwest winds will prevail across the waters except locally 
breezy conditions near the coastal gaps and prominent points 
through this evening and again Friday afternoon. Light to moderate
seas will continue through the forecast period with a mixed south
and northwest swell through late week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...None.

$$

PUBLIC FORECAST: AS
AVIATION: Dykema
MARINE: Dykema

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