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000
FXUS66 KMTR 210905
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
205 AM PDT Sun Apr 21 2024

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

.SYNOPSIS...
Issued at 205 AM PDT Sun Apr 21 2024

Warm inland temperatures expected throughout Monday before cooler,
unsettled weather returns Tuesday and continues through late week.
Light rain chances for Thursday night and into Friday.

&&

.SHORT TERM...
(Today and tonight)
Issued at 205 AM PDT Sun Apr 21 2024

Once low clouds this morning dissipate across the San Francisco
Peninsula and Monterey Bay region, expect mostly sunny conditions
across the region. Far interior areas will warm this afternoon into
the low-to-mid 80s with temperatures tapering off to the lower 60s
near the coast. Tonight, mostly clear sky conditions are expected
with a few passing high clouds in advance of an approaching weather
system. Temperatures are only expected to cool into the low-to-mid
50s to upper 40s along the immediate coastline.

&&

.LONG TERM...
(Monday through Saturday)
Issued at 205 AM PDT Sun Apr 21 2024

Monday will be quite warm inland, only a few degrees cooler than
Sunday. However, a southerly surge is expected to spread northward
up the Big Sur coastline and reach the San Francisco Peninsula by
mid-to-late afternoon. Thus, coastal/favored upslope drizzle will
possible beginning Monday afternoon and continuing through Monday
night/Tuesday morning.

Tuesday will bring the return of unsettled conditions and cooler
temperatures regionwide as an mid/upper level low approaches
southern California. Afternoon high temperatures both Tuesday and
Wednesday will struggle to warm out of the upper 50s near the coast
and 60s inland. There is also a 10-20% chance of patchy coastal
drizzle Wednesday morning.

Thursday will be mostly dry, but chances are increasing for light
rain over the region Thursday night into Friday. This will be as
troughing persists over the region while a shortwave trough moves
inland. Temperatures on Friday will struggle to reach the 60s near
the coast and in the hills while interior areas stay in the 60s.
Drier conditions return Saturday but temperatures will be similarly
cool.

&&

.AVIATION...
(06Z TAFS)
Issued at 1049 PM PDT Sat Apr 20 2024

VFR through the TAF period for most terminals. Moderate onshore
winds from earlier this evening have helped to mix out much of the
stratus. As a result, not expecting stratus to impact terminals
tonight with the exception of Monterey Bay briefly. Otherwise, light
winds persist overnight and increase into the afternoon tomorrow to
become breezy. Stratus does not appear to return until well beyond
the TAF period.


Vicinity of SFO...VFR. A FEW low clouds may drift over the
terminal in the early morning of Sunday, but not expecting CIGs to
form. Winds are still elevated at this hour, and are expected to
remain so through much of the night, easing only to about 10
knots. In the afternoon of Sunday, moderate winds return, but are
not expected to gust above 20 knots or so. Winds then ease into
the evening hours of Sunday.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Stratus may make a brief appearance over
the KMRY terminal in the early to mid morning of Sunday, bringing
MVFR conditions. Aside from this, expecting VFR from the late
morning onwards. Onshore winds return in the afternoon around 10-12
knots.

&&

.MARINE...
(Tonight through next Friday)
Issued at 904 PM PDT Sat Apr 20 2024

Fresh to strong northerly winds continue to build across the
coastal waters with near gale force gusts possible through early
Monday morning. Gale force gusts are expected over the far
northern outer waters in this same time period, but begin to
diminish late Sunday night. Isolated gale force gusts remain
possible across the far southern outer waters through Sunday
night. Northwest swell builds through Monday as gusty conditions
continue but looks to diminish by the middle of next week. Light
southerly swell continues to move through the waters this weekend
and through the upcoming work week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt
     to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm.

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

     Small Craft Advisory until 3 AM PDT early this morning for Pt
     Arena to Pt Reyes 10-60 NM.

     Gale Warning until 9 PM PDT this evening for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...AC
MARINE...SPM

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