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

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000
FXUS66 KMTR 230317
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
817 PM PDT Tue Aug 22 2017

.SYNOPSIS...Dry weather will prevail today with temperatures
near to slightly below normal for the middle of August. Low
clouds and fog will persist in the overnight and early morning
near the coast and in the valleys the next several days. An inland
warming trend is likely late in the week and into the upcoming
weekend due to strengthening high pressure.

&&

.DISCUSSION...as of 8:17 PM PDT Tuesday...The marine layer
remains well established this evening with a depth near 1,700
feet. Onshore winds will usher stratus and fog inland tonight and
Wednesday morning with temperatures steadily cooling back. A
nearly stationary, dry and closed mid-upper level low pressure
circulation is located west of the Central Coast, nearly 200 miles
west of Santa Maria. This low will advance eastward over
California Wednesday and Thursday while an upper level ridge
gradually builds in late this week behind this departing low. An
inland warming trend is likely for late week and this weekend as a
result of high pressure strengthening over the area.

&&

.PREV DISCUSSION...as of 1:51 PM PDT Tuesday...This morning`s overcast
conditions over most of the San Francisco Bay Area have
transitioned to a mostly clear afternoon for much of the area. Low
clouds are still lingering from Point Reyes northward as well as
the Monterey Peninsula. When all is set and done this afternoon,
high temperatures should generally top out in the 60s and low 70s
along the coast and upper 70s to perhaps the low 90s for interior
locations. Expect the warmest locations to be in interior San
Benito and Monterey Counties with mid 90s likely.

Synoptically an upper level low remains centered around 150 miles
offshore from Big Sur around 35N 124W. Models advertise this low
to push onshore by midweek as a broader longwave trough approaches
coastal British Columbia. Not expecting much day-to-day change in
temperatures for any particular location during this time with
high temperatures running near seasonal normals. This changes for
Friday as models show a ridge beginning to build over the Four
Corners and expanding west over the weekend. Interior areas will
return back to the 90s and 100s as a result. Long range guidance
suggests the ridge will remain parked over the Southwest with
above normal temperatures likely continuing into next week.

&&

.AVIATION...As of 4:50 PM PDT Tuesday...For 00z TAFs.Clear skies
prevail over most area terminals this afternoon. Low clouds
anticipated to push in through the Monterey Bay early affecting
KMRY/KSNS. Otherwise a compressed marine layer will result in a
later return of the stratus across other terminals as well as an
early clearing Wednesday morning.

Vicinity of KSFO...VFR conditions expected through late tonight.
Borderline IFR-MVFR cigs expected to return after midnight
tonight. Low clouds will scatter out around 16z-17z Wednesday
morning. Moderate west winds will prevail through this afternoon
with sustained winds of 15-20 kt with occasional gusts to 25 kt
possible. Winds will ease after 04z tonight.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR cigs expected to lower to IFR after
03z this evening. Low clouds will clear to the coast around 17z
Wednesday morning. Light to moderate west winds will prevail
through this afternoon becoming light after 03z tonight.

&&

.MARINE...as of 2:34 PM PDT Tuesday...Light to moderate winds
through midweek, with locally stronger winds through coastal gaps
during the afternoons. Building high pressure from the west will
bring stronger northerly winds and steep fresh swell. No
significant long period swell through the upcoming week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...SF Bay until 9 PM

&&

$$

PUBLIC FORECAST: Canepa
AVIATION: CW
MARINE: DRP


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