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000 
FXUS66 KMTR 251131
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
431 AM PDT Sun Jun 25 2017

.SYNOPSIS...Gradual cooling is forecast to continue through
Monday, mainly for inland areas. Little change is expected near
the coast. Look for areas of night and morning low clouds and fog
followed by sunny afternoons. Modest warming is expected during 
the second half of the week. But for the most part, temperatures 
will be near seasonal averages through the week.

&&

.DISCUSSION...As of 2:50 AM PDT Sunday...Low clouds have 
developed well inland overnight, similar to last night. Also, 
there are reports of patchy fog and drizzle near the coast. 
Onshore surface pressure gradients are about the same as 24 hours 
ago and the marine layer depth has held steady at about 2000 feet.
For the most part, expect today to be much like Saturday with low
clouds clearing inland by midday while coastal areas see only 
partial afternoon clearing. Afternoon highs near the coast will be
close to what they were yesterday while inland areas are expected
to be slightly cooler. 

Cooling will continue into Monday as a weak upper
trough...currently centered offshore along 130W...moves inland
across northern California. Temperatures by Monday will be about 3
to 5 degrees cooler than normal, which is a big change from the
triple-digit heat inland areas endured during the prolonged heat 
event that ended just a few days ago. Little change is expected
going into Tuesday. 

The trough will move off to our east by midweek and a weak upper
ridge is then forecast to develop over California during the
second half of the week. This will result in modest warming from
Wednesday through Saturday. But for the most part, temperatures 
will remain close to seasonal averages through the week. 
Precipitation is not expected other than patchy night and morning 
coastal drizzle during the next few days.

&&

.AVIATION...As of 04:22 AM PDT Sunday...For 12Z TAFs...Marine
layer re-established itself overnight with pockets of fog/dz. Ft
Ord and sodars put the depth near 1600-1800 feet. A mix of LIFR to
MVFR conditions will be possible this morning. Burn off will be
early to mid morning with VFR this afternoon. Cigs return again
tonight.

Vicinity of KSFO...MVFR to IFR cigs through roughly 17Z. Satellite
indicates possibly thinner clouds over SFO and thicker clouds to
the south. West winds will increase once again Sunday afternoon 
to around 15 to 20 kt with the onset of the seabreeze. Low cigs
will return close to 06Z

SFO Bridge Approach...Given possible thicker clouds over approach
burn off may be a little later than SFO.  17->18Z.

Monterey Bay Terminals...LIFR cigs for KMRY and IFR cigs at KSNS.
Patchy fog will also be poss. Conditions will begin to improve 
after 15z Sunday morning with low clouds scattering out around 17z
Sunday morning. Light west winds.

&&

.MARINE...as of 04:21 AM PDT Sunday...High pressure off the West
Coast will maintain northerly winds over the coastal waters
through next week. Winds will be locally stronger along the
immediate coast. Seas will be small with a dominant southerly
swell.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...SF Bay from 1 PM
             SCA...Pigeon Pt to Pt Pinos 0-10 nm from 1 PM
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm from 1 PM

&&

$$

PUBLIC FORECAST: Dykema
AVIATION: MM
MARINE: MM


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