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

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FXUS66 KMTR 261736

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1036 AM PDT Fri May 26 2017

.SYNOPSIS...Deep marine layer with nearly all areas starting the
day cloudy which will keep temperatures on the cool side of normal
today. Saturday will trend back towards seasonable temperatures as
high pressure begins to build. Dry and warmer Sunday and Monday.
Another trough begins to approach by Tuesday and Wednesday with a
modest cooling trend and continued coastal clouds.

&& of 08:04 AM PDT Friday...Only minor adjustments
made to the short-term forecast. Marine layer remains very deep
around 4000 ft this morning with widespread cloud cover for
coastal locations and for many interior areas. There have even
been reports of drizzle around the Monterey area. Similar to
yesterday, the clouds may be a bit slower to erode away with the
deep marine layer. Afternoon temperatures will range from the
middle 50s to 60s along the coast, and middle 60s to middle 70s
for the interior.

Temperatures will begin warming over the holiday weekend as a
ridge builds over the West Coast. By Monday interior locations
will warm to the middle 70s to middle 80s, with the southern
Salinas Valley warming to around 90.


.PREV of 2:46 AM PDT Friday...Profiler data shows the
marine layer is very deep, around 4000 feet with fairly cool
temperatures aloft. This has allowed higher based marine clouds to
spread over nearly all locations in the district. The sfo to sac
gradient is weaker this morning at 1.2 mb onshore with lighter
winds most locations. Nonetheless the widespread clouds and upper
trough just to our east will once again keep temperatures on the
cool side of normal today, especially inland.

The trough axis nudges inland over the Great Basin while high
pressure begins to build Saturday. This will allow inland
temperatures to trend back closer to normal with more readings
into the 70s vs the cool 60s forecast for today.

High pressure continues to build Sunday with inland areas warming
back into the 70s and lower 80s. So pleasant weather for the
upcoming holiday weekend with no real hot weather to contend with
but still warm enough to use the pool. Beaches will remain cool
with onshore flow in place. SST have trended a few degrees warmer
the last few days as stronger nw winds have eased allowing SST to
warm back into mid 50s and in turn keep overnight lows a little
more mild near the coast and coastal valleys.

It`ll stay seasonably warm inland for Memorial Day with inland
highs from the mid 70s to mid 80s. The beaches will stay in the
upper 50s and 60s as another trough will approach by Monday
afternoon with increasing onshore winds. The models almost want to
generate some qpf around the middle of next week with the next
trough but that seems dubious at this time so will keep the
forecast dry. Trend should be for cooling back to seasonable norms
Tuesday and Weds with longer range ecmwf wanting to build a warm ridge
the second half of next week.


.AVIATION...As of 10:36 AM PDT Friday...Widespread cloud cover
this morning with deep marine layer. Based on latest
trends...obs/satellite...delayed burn off of clouds until 20-21Z
for most terminals. There are some hints that clearing may not
happen at all, but conf is low for an all day event. Clouds come
back in tonight and potentially more compressed as high pressure
builds over the region. Earlier burn off on Saturday.

Vicinity of KSFO...MVFR cigs will linger through early this
afternoon. Delayed any clearing until around 20Z Cig hts will
fluctuate from 2500 to 3500 ft. Light S-SW winds, increasing to
become breezy in the afternoon. Stratus returns tonight.

SFO Bridge Approach...Similar to terminal.

Monterey Bay Terminals...MVFR Through 20Z. Light S-SW winds,
increasing in the afternoon to become breezy.

&& of 10:29 AM PDT Friday...Weak high pressure offshore
will result in relatively light winds and small seas along the
central coast. High pressure will increase over the weekend with
increasing winds on saturday and lasting through the Memorial


     .Tday...SCA...SF Bay from 12 PM




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