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000
FXUS66 KMTR 231005
AFDMTR

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

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

.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.

&&

.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...
(06Z TAFS)
Issued at 1025 PM PDT Mon Apr 22 2024

Robust surface to lower level cool air advection will deepen the
marine layer and fully weaken/mix out the marine layer temperature
inversion tonight. Stratus will move inland, cool air advection
and upsloping flow resulting in patchy drizzle. Radiative warming
returning Tuesday will result in plenty of mixing with
sufficiently drier air resulting in VFR conditions Tuesday.

Vicinity of SFO...VFR at the moment with MVFR stratus hanging
along the coast. There is a decent chance this stratus reaches the
terminal tonight, and with the deep marine layer, it may even
produce some light drizzle in the early morning. Flight conditions
will improve through the day Tuesday with a moderate onshore
breeze.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...The early return of stratus has
materialized tonight and MRY, SNS and WVI are all under a dense
MVFR ceiling. The deep marine layer is expected to persist through
Tuesday, although there may be some improvement as daytime heating
mixes out some of the clouds.

&&

.MARINE...
(Today through Sunday)
Issued at 304 AM PDT Tue Apr 23 2024

A weak low pressure system NW of San Francisco will continue to
support moderate to fresh southerly winds over the coastal waters
today. This system will gradually weaken Tuesday night, 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 from 9 AM this morning to 9 PM PDT this
     evening for Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Flynn
MARINE...Flynn

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