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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS66 KMTR 121131
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
431 AM PDT Fri Apr 12 2024

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

.SYNOPSIS...
-- Changed Discussion --
Issued at 421 AM PDT Fri Apr 12 2024

Cooler and cloudier for Friday as highs fall back into average
range as the next rain-maker nears. Expect a breezy to gusty
afternoon with some light pre-frontal rain, with the main rain
band arriving overnight. Showers and storm chances are expected
through Saturday, with lingering showers Sunday.
-- End Changed Discussion --

&&

.SHORT TERM...
-- Changed Discussion --
(Today and tonight)
Issued at 421 AM PDT Fri Apr 12 2024

It`s weather whiplash as the region goes from warm and sunny to cool
and cloudy for the end of the work week.

Temperatures will top off in the 50s and 60s for most areas, with
only a few more interior areas venturing into the 70s, quite the
difference from yesterday.

This cool and cloudy change of pace is due to the trough building
along the west coast, which will have a cold front move through the
Bay Area and Central Coast tonight and the front`s parent low move
through over the weekend.

Southwest winds build ahead of the front this afternoon, along with
some light pre-frontal rain. Winds will be  breezy across the region
but will be particularly gusty on higher peaks in Monterey and San
Benito Counties.

The main rain band arrives along the cold front into the night,
bringing moderate rainfall, with shower activity lasting behind it,
and weakening winds. The most recent forecast updates have delayed
the time of arrival of the cold front, and signal that this could
still be a more late night/early morning set passage.
-- End Changed Discussion --

&&

.LONG TERM...
-- Changed Discussion --
(Saturday through Thursday)
Issued at 421 AM PDT Fri Apr 12 2024

The weekend will see the cold front`s parent low focusing over the
Bay Area and Central Coast, providing scattered showers and storm
chances through Saturday, with some lingering showers into Sunday.
Storm chances will peak around 25% into Saturday evening and into
the early night, with the focus being off the coast of Santa Cruz Co
and the Monterey Bay.


While the cold front will offer most of the weekend rain fall, the
shower and storm activity behind will add up over time.

As of the current forecast, Rainfall totals from Friday through
Sunday afternoon look to range from:

-0.4" to 0.75" for most inland areas
-0.75" to 1.25" for coastal areas and higher elevations in the North
Bay
-1.25" to 2" Santa Cruz Mtns and the Santa Lucias.
- above 2" for the highest peaks along the Big Sur Coast


A ridge pattern builds in quickly behind the weekend`s rains,
allowing for dry weather to return into next week. This will also
put the region into another warming trend with widespread 60 and 70
degree highs expected in the middle of the work week.
-- End Changed Discussion --

&&

.AVIATION...
(06Z TAFS)
Issued at 1106 PM PDT Thu Apr 11 2024

Currently VFR with MVFR overnight with all stations expected to
receive stratus overnight. Guidance indicates that IFR conditions
may possibly develop at MRY, SNS, OAK, SFO, and STS overnight. Low
confidence that fog will develop at STS and APC overnight but a few
models suggest that some could develop between 12-18Z. Winds will
pick up tomorrow ahead of an incoming system with breezy to gusty SW
winds expected. Rain chances increase heading into late Friday/early
Saturday with STS, APC, OAK, and SFO expected to receive showers at
the end of the TAF period. Showers are expected to be in the
vicinity of SJC, LVK, MRY, and SNS at the end of the TAF period.

Vicinity of SFO...Currently VFR with MVFR conditions overnight as
stratus returns. Breezy to at times gusty SW winds will continue
through the TAF period with stronger wind gusts possible starting
Friday afternoon. Rain will approach SFO Friday evening with light
rain starting late Friday night.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR to MVFR. Guidance indicates that IFR
conditions may develop overnight but confidence remains low so will
continue to monitor. Ceilings will start to light by the afternoon
with VFR conditions returning. Light NW to SW winds overnight with
breezier NW to SW winds returning towards the end of the TAF period.

&&

.MARINE...
-- Changed Discussion --
(Today through Wednesday)
Issued at 421 AM PDT Fri Apr 12 2024

Moderate to fresh northwesterly breezes to continue into the
morning. During the afternoon, winds will strengthen to fresh to
strong and transition southwesterly ahead of an incoming low
pressure system. This system will bring rain, near gale force
gusts,  and a 20% chance for thunderstorms to the coastal waters
through  Saturday. A chance for occasional gale force gusts
remains possible  particularly in the southern coastal waters.
Moderate period  northwesterly swell will continue through the
weekend.
-- End Changed Discussion --

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 3 PM PDT
     Saturday for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm-Pigeon
     Pt to Pt Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10
     nm.

     Small Craft Advisory from 9 AM to 3 PM PDT Saturday for Pt Arena
     to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.

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

     Small Craft Advisory until 9 AM PDT this morning for Pt Pinos to
     Pt Piedras Blancas 0-10 nm.
-- End Changed Discussion --

&&

$$

SHORT TERM...Murdock
LONG TERM....Murdock
AVIATION...Sarment
MARINE...Kennedy

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