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000
FXUS66 KMTR 131046
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
346 AM PDT Sat Apr 13 2024

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

.SYNOPSIS...
Issued at 339 AM PDT Sat Apr 13 2024

The rain band builds inland this morning, offering widespread rain
and breezy to gusty winds. Showers and storm chances last through
the day and into the night. Storm chances decrease overnight, but
showers linger into Sunday afternoon before dry weather returns.

&&

.SHORT TERM...
(Today and tonight)
Issued at 339 AM PDT Sat Apr 13 2024

The main rain band is moving inland along the cold front, bringing
moderate rainfall. The rain band will become less organized as it
continues to move inland, leading to more widespread rain but with
reduced rain rates. Shower activity lasts behind the front, with
weaker, but still breezy winds expected through the day. The cold
front`s parent low moves onshore and inland in the afternoon and
into the night, providing additional scattered showers and storm
chances.

Storm chances will peak around 30% into this evening and into the
early night, with the focus being off the coast of Santa Cruz Co and
the Monterey Bay.

&&

.LONG TERM...
(Sunday through Friday)
Issued at 339 AM PDT Sat Apr 13 2024

Thunderstorm chances dissipate into early Sunday morning with
showers lingering into the afternoon before exiting.

Afterwards, a ridge pattern builds in quickly, allowing for dry
weather to return into next week. This will also put the region into
another warming trend with highs ranging from the 60s (along the
coast) to the 80s (in more interior areas) expected in the middle of
the work week and into the next weekend.

The longer term forecast models keep the ridge pattern in place
beyond next weekend, but the ridge shifts slightly east, allowing
for more onshore flow. This will cool temperatures, but still
prevent rain from returning to the forecast.

&&

.AVIATION...
(06Z TAFS)
Issued at 1044 PM PDT Fri Apr 12 2024

Mix of VFR and MVFR. The ASOS at STS is reporting light to heavy
rain as the first showers enter the North Bay. Rain chances will
increase north to south through the early to mid morning hours on
Saturday with widespread light to moderate rain. Gusty southerly
winds continue through the TAF period. CIGs will gradually lower as
the front approaches with MVFR CIGs expected overnight. VFR CIGs
will return by mid Saturday morning after the frontal passage
occurs. Thunderstorm chances will start to increase heading into
Saturday afternoon in the post frontal environment.

Vicinity of SFO...VFR transitioning to MVFR overnight as widespread
rain approaches the airport. Gusty S to SW winds will continue
through the TAF period with gusts up to 30 knots expected. Radar
shows showers located off of the coast and heading inland. Rain
should reach SFO closer to 09Z around the time of frontal passage
with MVFR CIGs expected during this time. VFR CIGs to return by mid
to late morning after the front passes.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR transitioning to MVFR
overnight. Gusty S to SW winds will continue with sustained winds up
to 20 kts and occasional higher gusts possible. CIGs and visibility
look to drop as the main rain band reaches the Central Coast between
10-11Z with light to moderate widespread rain possible. VFR CIGs
should return in the post frontal environment by the mid to late
morning.

&&

.MARINE...
(Today through Thursday)
Issued at 339 AM PDT Sat Apr 13 2024

Breezy fresh to strong winds continue across the coastal waters
ahead of an incoming low pressure system and it`s cold front. The
occasional near gale force gust, particularly in the southern
coastal waters, cannot be ruled out. With this system, widespread
light to moderate rain will continue through Saturday morning
before  transitioning to a more scattered, convective
precipitation mode  by the afternoon. Thunderstorm potential
increases to 25 to 30%  Saturday afternoon and evening with
chances decreasing overnight  into Sunday morning. Moderate period
northwesterly swell will  continue to build through the waters
through Saturday before  beginning its abating trend Sunday.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Sunday
     for SF Bay N of Bay Bridge.

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

     Small Craft Advisory from 9 AM this morning to 9 PM PDT this
     evening for Pt Arena to Pt Reyes 10-60 NM-Pt Reyes to
     Pigeon Pt 0-10 nm.

&&

$$

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

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