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000
FXUS66 KMTR 251756
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1056 AM PDT Thu Apr 25 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1201 AM PDT Thu Apr 25 2024

Cool temperatures will continue today. A cold front will bring
a chance for light rain beginning tonight, with strong winds
Friday night. Increasing sunshine will kick off a warming trend
Sat-Tue.

&&

.SHORT TERM...
(Today and tonight)
Issued at 1201 AM PDT Thu Apr 25 2024

A coastal surface trough will continue to weaken and move inland,
allowing a low-amplitude ridge to build. This will cause the
marine layer to compress to about 1,500 ft. Compared to the 4,000
ft deep marine layer observed Wednesday, the low overcast today
will be more limited to the coast and adjacent low valleys. The
standard NW flow will also return as the trough weakens. The cool
temperatures will continue, with highs generally in the 60s. This
ridge pattern will be short lived as a cold front moves through on
Friday.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 1201 AM PDT Thu Apr 25 2024

Some light rain is possible starting ahead of the cold front
Thursday night, with low PoPs lasting though the day Friday.
22/26 members of the SREF have some precipitation falling at SFO
between Thursday night and Friday, but only 4 of them are above
0.05" of accumulation, and none of those are above 0.1". Similar
results are found throughout the Bay Area, with slightly more
bullish results along the Central Coast. As such, I have
increased the NBM PoPs to at least 15% to ensure a slight chance
of rain is mentioned, but did not increase the QPF from the WPC
guidance, which is near zero. There`s a decent chance some rain
falls late Thursday-Friday, but it will be light.

The bigger impact will be from strong NW winds behind the cold
front. 24 hours ago, it looked like a slam dunk wind advisory
along the coast, but the models have backed off since then. NBM is
on the high side of the guidance, but only shows a slight chance
of exceeding 40 mph gusts along the coast on Friday night. The
timing of the strongest winds has also shifted from Friday
afternoon to overnight Friday. Based on this, and the fact that
other deterministic models are even less aggressive, we are not
hoisting a wind advisory at this time. That being said, there will
be plenty of gusts above 30 mph on Friday and Saturday with some
minor impacts expected.

The weekend will feature clearing skies and slightly warmer
temperatures, although Saturday will still be breezy. The gradual
warm-up will continue through early next week, as the region
returns to seasonal temperatures under mostly clear skies. The
next threat of rain arrives late next week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1056 AM PDT Thu Apr 25 2024

Satellite shows low ceilings shuffling through the region
causing MVFR conditions over most of the terminals. Onshore winds
will continue to build to breezy and gusty through the afternoon
with some terminals seeing relief overnight to moderate winds. SF
Bay terminals are expected to remain gusty and breezy through the
TAF period. Stratus may lift to VFR for brief moments this afternoon
before lower ceilings will return tonight bringing a mix of VFR/MVFR
conditions overnight. VFR is expected to return by Friday morning.

Vicinity of SFO...MVFR with W/NW breezy and gusty winds. Models
suggest a short brief moment of VFR near the afternoon but had low
confidence to include in TAFs. If lifting does occur, expect MVFR
conditions to linger near by the terminals. Winds will remain breezy
and gusty through the TAF period.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR through most of the TAF period for
KMRY but KSNS may see a temporary lift to VFR this afternoon. Winds
will become breezy and gusty this afternoon, before transitions to
moderate overnight. VFR expected to prevail after 12Z.

&&

.MARINE...
Issued at 1056 AM PDT Thu Apr 25 2024

Moderate northwesterly winds persist through Friday morning with
occasional fresh to strong gusts through various portions of the
coastal waters, mostly in the southern waters. Winds strengthen
to become strong and gusty into Friday afternoon with gale-force
gusts likely near the Big Sur coast. These strong and gusty
northwesterly winds last through the weekend and into at least the
early portion of next week, bringing hazardous conditions for
small craft vessels. Moderate period northwest swell will
continue to move through the waters this weekend, with a new
longer period northwest swell train entering the waters Sunday.
Light, long period southerly swell continues through end of
forecast period.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay.

     Small Craft Advisory from 9 AM to 3 PM PDT Friday for Mry Bay-
     Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60
     NM.

     Small Craft Advisory until 3 PM PDT this afternoon for Pigeon Pt
     to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos
     to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this
     evening for Pigeon Pt to Pt Pinos 0-10 nm.

     Gale Warning from 3 PM this afternoon to 9 PM PDT this evening
     for Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...Flynn
LONG TERM....Flynn
AVIATION...SO
MARINE...SO

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