FXUS66 KMTR 192051

Area Forecast Discussion
National Weather Service San Francisco Bay Area
151 PM PDT Mon Aug 19 2019

.SYNOPSIS...A deep marine layer will prevail through today,
maintaining widespread morning low clouds and cooler than normal
inland temperatures. Warmer temperatures will develop by midweek
and continue through the upcoming weekend as high pressure


.DISCUSSION...as of 1:52 PM PDT Monday...The deep marine layer
has prevented the usual mid-day clearing across parts of the San
Francisco Bay Area and central California coast. As of 1 pm PDT,
Monterey, San Francisco, and Oakland Airports were all still
reporting overcast skies. While the slow and gradual clearing
trend is expected to continue as the afternoon progresses, some
locations along the immediate Pacific coast may not see the sun
shine at all today. The clouds are influencing temperature trends
this afternoon as most airports are running about 2 to 7 degrees
cooler than 24 hours ago. By the time the afternoon concludes,
high temperatures will reach the 60s along the immediate coast and
70s to 80s for inland locations. The low clouds are expected to
return again tonight with the chance of some light drizzle along
the Pacific coast.

Synoptically, an upper level ridge presently centered over the
Southern Plains is forecast to build and broaden westward towards
the Desert Southwest and Baja California over the next several
days. This will result in a gradual compression of the marine
layer by the middle of the week. Additionally, a noticeable
warming trend will take place through at least mid-week with the
most significant day-to-day warm-up occurring from Tuesday to
Wednesday. Low 90s will become increasingly more likely on
Wednesday across some of the region's typical hot spots such as
King City, Gilroy, Livermore, and even Santa Rosa. Can't rule out
some rural far-inland locations approaching the upper 90s/low
100s, but at this point don't think last the max temperatures
achieved last week will be repeated this week for the core
population centers.

Forecast guidance shows an upper level trough approaching the
Pacific Northwest on Wednesday and Thursday with some
precipitation potential for parts of Oregon and Washington State.
While the San Francisco Bay Area will be well south of any
precipitation chances, the positioning of this trough will help
prevent additional warming for our region. The current forecast by
late week and into the weekend calls for forecast highs to
generally fall within a several degrees of normal along the coast
with inland locations at or slightly above normal.

As mentioned in the previous overnight discussion, models are
suggesting the potential for an uptick in tropical activity well
to our south along the Baja California coast by the weekend and
into early next week. There still remains plenty of uncertainty
this far out, but will have to keep tabs on any development as
northbound moisture transport to parts of the southern California
coast and possibly even the central California coast isn't
completely out of the question by early next week.


.AVIATION...As of 10:36 AM PDT Monday...For 18z tafs. The marine
layer is still fairly deep at around 2500 ft AGL per the Fort Ord
Profiler. Satellite imagery shows stratus remains over much of
the region this morning, but is finally beginning to dissipate.
VFR conditions to prevail by this afternoon with clearing
currently expected between 18z-20z. MVFR to IFR cigs to return
this evening and prevail again overnight for most sites. VFR
conditions will last later into the evening for more inland
locations. W to SW winds this morning increasing this afternoon to
10-15 kt with locally higher gusts at KSFO.

Vicinity of KSFO...MVFR cigs to continue until around 19z-20z. VFR
conditions expected this afternoon with models showing an earlier
return of MVFR cigs this evening. SW to W winds around 10 kt this
morning increasing to 15 kt this afternoon with gusts 20-25 kt
after around 20z-21z.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR ceilings until 18Z-20Z. Satellite
shows a decent feed of stratus into the Peninsula. It is possible
that MVFR cigs could linger around KMRY longer than currently
forecast. Will keep an eye on satellite/obs and update the taf as
needed. Light winds this morning turning onshore in the afternoon
and increasing to 10-15 kt. VFR conditions expected in the
afternoon before MVFR cigs return early to mid evening and for the
overnight hours.


.MARINE...as of 8:12 AM PDT Monday...Generally light winds today
and tonight across the coastal waters as high pressure off the
California coast weakens and a surface low develops offshore of
the Pacific Northwest. Locally gusty winds are expected later
today and into tomorrow over the inner coastal waters south of
Point Sur. Mixed seas will continue with shorter period northwest
waves at around 8 to 10 seconds, a light longer period west swell,
and a light southerly swell.


.Tngt...SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm from 3 AM




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