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000
FXUS66 KMTR 250355
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
855 PM PDT Wed Apr 24 2024

...New UPDATE...

.SYNOPSIS...
Issued at 228 PM PDT Wed Apr 24 2024

A deep marine layer and expansive cloud coverage will keep
temperatures cool through Thursday before stronger winds arrive
Friday. Clearer skies and slightly warmer temperatures are
expected this weekend.

&&

.UPDATE...
Issued at 853 PM PDT Wed Apr 24 2024

Areas of the North Bay coast, East Bay Hills and Santa Cruz
Mountains saw light rain/drizzle today with amounts totaling up to
0.04". Due to abundant cloud cover, temperatures struggled to warm
out of the low-to-mid 60s. Similar conditions will be possible
overnight, but rainfall amounts won`t amount to much and are likely
to range from trace amounts to a few hundredths of an inch.
Overnight temperatures are expected to cool into the mid 40s to
low 50s. No updates are anticipated at this time.

&&

.SHORT TERM...
(This evening through Thursday)
Issued at 251 PM PDT Wed Apr 24 2024

Another cloudy and cool afternoon, but with a slightly different
setup compared to yesterday as the the low pressure has moved closer
to the coast. While the low continues to push plenty of clouds
onshore cloud heights and marine layer thickness increased as the
low moved closer. What does that mean? Well it will be slightly
harder for the cloud cover to erode this afternoon.

The low pressure slowly makes its way inland tonight. The deeper
marine layer may limit fog development to only a few patches in the
North Bay, otherwise expect another cloudy night followed by a cool
and cloudy Thursday.

While Thursday continues the trend of cloudy skies, the upper level
pattern shifts, allowing for more northwest flow and bringing back
some breezier northwest winds into the forecast.

&&

.LONG TERM...
(Thursday night through next Tuesday)
Issued at 251 PM PDT Wed Apr 24 2024

Still cloudy and cool with some pockets of drizzle for early Friday
as the low pressure exits and the marine layer compresses just
enough for lower clouds. Friday`s pressure gradient change from the
low`s exit will make for even breezier conditions for Friday
specifically for higher peaks and along the Big Sur coast. The more
active winds will allow for better clearing of cloud coverage in
the late afternoon

While the new upper level pattern still allows for onshore flow,
cloud cover becomes less pervasive. While the immediate coast will
continue to struggle with cloud cover, most areas slightly more
inland and well into the interior will see quicker clearing times.
This will place most areas back into the 60s and 70s into the next
work week, while the coast will stick to around 60 degree highs.

Longer term models still struggle with the next pattern change at
the beginning of next month. While the ECMWF families place rain
chances back into the forecast, others favor more cloudy and drizzly
conditions, and a few keep the moisture well to the north.

&&

.AVIATION...
(00Z TAFS)
Issued at 510 PM PDT Wed Apr 24 2024

VFR at all terminals with MVFR to return by late this evening.
Broken to overcast conditions should remain in place for the
majority of the TAF period with ceiling heights decreasing heading
into the evening hours. As the night progresses, an upper level low
will continue to exit the region and a shortwave ridge will start to
build this will help to compress the marine layer and push ceilings
down to low-end MVFR. West to northwest winds will start to pick up
mid to late tomorrow morning with gusts up to 25 knots possible.
Gustier conditions will then continue through the end of the TAF
period and into the next.

Vicinity of SFO...VFR transitioning to MVFR overnight. Transition to
westerly flow has been pushed back slightly with obs showing breezy
southwesterly winds continuing. Winds are expected to gradually
shift more westerly heading into the evening hours and continue
through the end of the TAF period. Winds will start to pick up mid
to late tomorrow morning with gusty conditions expected through the
end of the TAF period. Gusts up to 25 knots are currently expected.
T he caveat to this is that recent guidance has shown winds trending
higher than previously forecast which may result in gusts needing to
be upped in future TAFs.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR with moderate to high
confidence in transition to MVFR overnight. Gusty conditions at MRY
continue heading into the evening with winds expected to weaken and
become more moderate overnight. For both MRY and SNS, westerly winds
prevail through the TAF period with moderately gusty winds returning
by mid to late tomorrow morning.

&&

.MARINE...
(Tonight through next Monday)
Issued at 853 PM PDT Wed Apr 24 2024

Gentle to moderate NW winds continue into Friday with occasional
moderate to fresh gusts possible throughout portions of the
coastal waters. Gustier fresh to strong winds with near gale
force and isolated gale force gusts possible heading into Friday
as an upper level trough and surface low pressure system move
inland. Moderate period northwest swell will continue to move
through the waters through Saturday. Light long period southerly
swell continues through end of forecast period.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 9 PM PDT Thursday for Mry Bay.

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

     Small Craft Advisory from 3 AM to 3 PM PDT Thursday for Pigeon
     Pt to Pt Pinos 10-60 NM-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory from 9 AM Thursday to 3 AM PDT Friday for
     Pt Pinos to Pt Piedras Blancas 0-10 nm.

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

&&

$$

UPDATE...RGass
SHORT TERM...Murdock
LONG TERM....Murdock
AVIATION...Kennedy
MARINE...Kennedy

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