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000
FXUS66 KMTR 301924
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1224 PM PDT Tue May 30 2023

...New SYNOPSIS, SHORT TERM, LONG TERM...

.SYNOPSIS...
Issued at 1152 AM PDT Tue May 30 2023

Cooler temperatures in the short term as winds return to
northwesterly. Breezier winds expected on Wednesday. A warming
trend is forecast for the end of the week that could potentially
return temperatures back to seasonal norms over the weekend.

&&

.SHORT TERM...
(This afternoon through Wednesday)
Issued at 1152 AM PDT Tue May 30 2023

Current satellite showing most of the high clouds associated with
the stubborn, slow moving upper low are now mostly out of our region
with a few lingering here and there. As the low moves inland through
this evening, north/northwest winds will increase along coastal
areas through midweek. Wednesday kicks off a warming trend with
high temps near normal in the North Bay, still 5 to 10 below
normal elsewhere across the area. Some remnant cloudiness from a
deeper marine layer will likely remain through Wednesday as a weak
trough associated with a weakening upper low in the Gulf of Alaska digs
in slightly behind the exiting upper low.

&&

.LONG TERM...
(Wednesday night through next Monday)
Issued at 1152 AM PDT Tue May 30 2023

The longer term outlook into the weekend is perhaps the more
interesting one, as ridge is progged to build in behind both
exiting troughs. With the ridging persisting into the weekend,
expect afternoon highs near normal by the weekend (mid-to-upper
80s inland, upper 60s to mid-70s near lower lying coastal areas,
60s along the coast). Along with the building high pressure will
be the return of our well-known compressed marine layer, in which
we can expect clearer skies in the late mornings and afternoons,
but more local fog impacts during the morning hours. Regarding
heat risk and specific temps this weekend, not expecting much in
the way of widespread heat impacts with Heat Risk only in the
minor category with some isolated pockets of moderate on Sunday
for the South Bay. These levels of Heat Risk correspond with
impacts to those particularly sensitive and vulnerable to the
heat, especially those who are outdoors without effective cooling
and/or adequate hydration. Parts of the South Bay, inland and
northern North Bay, East Bay hills, and interior Monterey and San
Benito counties all share an 80-90% chance of afternoon highs
above 80F Sunday. The chance for highs greater than 90F in these
areas is generally less than 20%, with the exception being
northern Napa county which is likely to hit 90F on Sunday.
Otherwise beyond the weekend expect a slight cooling trend to
start next week as it appears a troughing pattern is likely to
return with temps a few degrees below normal.

&&

.AVIATION...
(18Z TAFS)
Issued at 1116 AM PDT Tue May 30 2023

Becoming VFR into the afternoon with passing mid-level clouds and
moderate to breezy westerly winds. Winds reduce into the night as
low cloud cover moves inland and fills over the bays. Expect MVFR
CIGs for most areas that will last into the late morning and early
afternoon Wednesday. Moderate to breezy westerly winds return
Wednesday afternoon.

Vicinity of SFO...Becoming VFR for the afternoon and evening.
Expect breezy westerly winds that reduce into the night as MVFR
CIGs fill over the SF Bay. VFR returns into late Wednesday
morning with another breezy afternoon to follow.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR lingers into the early afternoon.
VFR and moderate winds are expected into the night. Light winds
return in the late evening with MVFR CIGs.

&&

.MARINE...
(Today through Sunday)
Issued at 1116 AM PDT Tue May 30 2023

Expect widespread northwest winds Tuesday into Wednesday. These
winds will then increase on Wednesday creating steeper wind waves.
Meanwhile, a mix of northwest and southerly swells prevail
through the week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 3 PM PDT Wednesday for PZZ540.

     Small Craft Advisory from 3 PM this afternoon to 9 AM PDT
     Wednesday for PZZ570.

     Gale Watch from Wednesday morning through Wednesday afternoon
     for PZZ570.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Murdock
MARINE...Murdock

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