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000
FXUS66 KMTR 231734
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1034 AM PDT Tue Apr 23 2024

...New AVIATION...

.SYNOPSIS...
Issued at 304 AM PDT Tue Apr 23 2024

Cooler, unsettled conditions return today and continue throughout
late week with coastal drizzle possible this morning and again
tonight into Wednesday morning. Then, light rain possible for
Thursday night and into Friday.

&&

.UPDATE...
Issued at 904 AM PDT Tue Apr 23 2024

A healthy marine layer continues to offer almost CWA-wide stratus
that will struggle to erode through the morning. An offshore eddy
looks to continue to push stratus on land, preventing widespread
clearing until the afternoon. This delay in clearing will result
in slightly cooler highs for the areas just a bit inland from the
coast, while the more interior areas and the immediate coast`s
temperatures will stay on track from the overnight forecast.

&&

.SHORT TERM...
(Today and tonight)
Issued at 304 AM PDT Tue Apr 23 2024

Coastal drizzle is being observed across the Central Coast early
this morning and will be likely in other coastal/favored upslope
spots across the region through midmorning. Temperatures will warm
into the upper 50s to lower 60s near the coast and up to the lower
70s in the warmest interior spots. Areas where cloud cover persists
will struggle to warm out of the lower 60s.

Tonight, expect more drizzle in coastal/favored upslope spots across
the region as an upper level low approaches southern California.
Overnight temperatures will range from the mid 40s to low 50s.
Increased cloud cover will spread inland as well, similar to this
morning.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 304 AM PDT Tue Apr 23 2024

Cooler, unsettled conditions will continue Wednesday through Friday
as the aforementioned upper level disturbance moves inland.
Afternoon maximum temperatures will stay in the upper 50s to low 60s
near the coast with 60s inland. Overnight minimum temperatures will
cool into the mid 40s to low 50s with a few spots in the mountainous
terrain dropping into the low 40s.

Light rain will be possible late Thursday evening into the first
half of the day on Friday, yet rainfall amounts are expected to
remain light. Northwest winds are also forecast to increase with
gust near the coast and in the higher terrain approaching 25-45 mph
both Thursday and Friday. As a shortwave ridge builds in wake of the
exiting trough, temperatures will warm slightly to near seasonal
averages by the upcoming weekend.

&&

.AVIATION...
(18Z TAFS)
Issued at 1034 AM PDT Tue Apr 23 2024

The weak low pressure system continues to influence a stable, low
marine layer. Satellite shows stratus socked in over all terminals
causing mostly MVFR conditions that will likely clear later than
usual time. Models hint at 19-20Z but higher confidence that most
terminals will become VFR near 20-21Z. Stratus is expected to return
later tonight causing another round of MVFR conditions for majority
of the terminals. Winds will be predominately moderate to breezy out
of the SW in the afternoon, then diminishing overnight.

Vicinity of SFO...MVFR stratus continues but is expected to slowly
improve to VFR near 20-21Z but borderline MVFR ceilings will
linger through most of the day. Gusty winds will help ceilings
lift. S/SW winds will remain breezy through most of the day, then
diminishing overnight.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR with ceilings lifting to VFR near 20-
21Z. Timing is a bit uncertain, as the surface heating start to play
a role in clearing some of the stratus out over the terminals. S/SW
moderate breeze is expected to become breezy and gusty in the
afternoon before returning to light to moderate overnight. MVFR
conditions return tonight.

&&

.MARINE...
(Today through Sunday)
Issued at 924 AM PDT Tue Apr 23 2024

A weak low pressure system off the coast of San Francisco will
continue to bring moderate to fresh southerly winds over the
coastal waters today. This system will gradually weaken tonight,
allowing northwest flow to return by Wednesday. Sea heights will
remain moderate through the week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this
     evening for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm.

     Small Craft Advisory until 9 PM PDT this evening for Pt Pinos to
     Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...SO
MARINE...SO

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