674
FXUS66 KMTR 250050
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
550 PM PDT Fri May 24 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1231 AM PDT Fri May 24 2024

Cool temperatures this weekend with a slight warm up slated for
next week. Quiet, summer-like pattern persists through the period.

&&

.SHORT TERM...
Issued at 205 PM PDT Fri May 24 2024 (This evening through
Saturday)

As we head into the un-official kick off to summer this weekend it
doesn`t really feel like summer. The latest 24 hour trends
indicate many locations running 5 to 10 degrees colder today than
Thursday. Why the big change? The longwave pattern changed thanks
to a passing upper level trough and a weak surface front. This
trough and colder air aloft help to increase onshore flow too.
SFO-SAC gradient is pushing 3.3mb this afternoon, which is also
stronger than yesterday. The increased onshore flow has also kept
the marine stratus lingering well into the afternoon. Pretty
impressive when one looks at the visible satellite and still sees
clouds spreading across the SF Peninsula and into the East Bay
Hills. Needless to say, temperatures were nudged downward today
around SF Bay due to lingering clouds. One final note with
today`s onshore flow, peak gusts of 45-50 mph have been observed
in the East Bay Hills.

Tonight through Saturday: Onshore flow will ease overnight, but
still remain onshore. Given persistent onshore flow will expect
another night of widespread stratus moving inland. Have added
patchy fog and drizzle to the coast/favored upslope areas. After a
cloudy start to the day on Saturday some clearing will be had, but
stratus will lingering around Monterey Bay and SF Peninsula.
Another cool day with max temps in the upper 50s/60s coast and
60s/70s inland. Forecast onshore gradients will be close 3mb again
so gusty winds in the afternoon seem plausible.

&&

.LONG TERM...
Issued at 217 PM PDT Fri May 24 2024 (Saturday night through next
Thursday)

Slight shift in the upper level pattern for the rest of the
weekend through Memorial Day will lead to a gradual warm up
through next week. 500 mb heights will increase with warming 850
mb temps all yielding warmer temperatures. Closer to seasonal
averages by the end of next week as far interior locations
approach 90 degrees. Night and morning clouds clearing back to
the coast each afternoon will also continue.

&&

.AVIATION...
(00Z TAFS)
Issued at 550 PM PDT Fri May 24 2024

Most of the region has cleared out, but MVFR stratus continues over
the SF Bay terminals and the area around MRY. Not expecting any
clearing for those terminals for the rest of the day; if they do
clear out, it will be short-lived and transitory. Breezy
northwesterly winds will continue into the evening, diminishing at
night before resuming Saturday afternoon. High confidence in further
stratus development across the region this evening, except at the
North Bay terminals where confidence is moderate. Along the coast,
and in the SF Bay and Monterey Bay regions, ceilings are expected to
decrease to IFR-LIFR. Stratus mixes out late Saturday morning with
breezy northwest flow resuming in the afternoon.

Vicinity of SFO... MVFR stratus continues through the day. Strong
west winds gusting to 30 gusts will continue through the evening. At
this time, low confidence that winds will gust above 35 knots. Will
monitor evolution of winds throughout the day and will amend TAF if
necessary. High confidence of MVFR or marginal IFR stratus at the
terminal area tonight, clearing late Saturday morning with strong
west winds Saturday afternoon.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals... MRY should expect MVFR ceilings through
the day, with some greater uncertainty at SNS although continuing
ceilings are also favored there. Breezy and gusty northwest winds
continue through the evening. Overnight, ceilings drop to the IFR-
LIFR level across the region. Clearing time is expected late
Saturday morning at SNS, and a moderate confidence that MRY clears
out at a similar time as well, although some model output keeps
ceilings through Saturday.

&&

.MARINE...
(Tonight through next Thursday)
Issued at 550 PM PDT Fri May 24 2024

Strong winds hazardous to small craft continue through the day
with  gale force gusts possible along the coast near Point Reyes
north to  Point Arena. Winds will gradually diminish overnight but
gusty winds  and steep wind waves will continue, especially in the
northern outer  waters. A strengthening high pressure system in
the eastern North  Pacific will contribute to increased winds and
wave heights starting  in the middle part of next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay-
     Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60
     NM-SF Bay N of Bay Bridge.

     Small Craft Advisory from 3 PM to 9 PM PDT Saturday for Mry Bay.

     Small Craft Advisory until 3 AM PDT Sunday for Pt Arena to Pt
     Reyes 0-10 nm.

     Small Craft Advisory until 9 AM PDT Saturday for Pt Reyes to
     Pigeon Pt 0-10 nm.

     Small Craft Advisory from 3 PM Saturday to 3 AM PDT Sunday for
     Pigeon Pt to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras
     Blancas 0-10 nm.

     Small Craft Advisory until 3 AM PDT Saturday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

     Small Craft Advisory until 9 AM PDT Sunday for Pt Arena to Pt
     Reyes 10-60 NM.

     Small Craft Advisory from 3 PM Saturday to 9 AM PDT Sunday for
     Pigeon Pt to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...MM
LONG TERM....MM
AVIATION...DialH
MARINE...DialH

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