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000
FXUS66 KMTR 221806
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1106 AM PDT Mon Apr 22 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 118 AM PDT Mon Apr 22 2024

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

&&

.UPDATE...
Issued at 753 AM PDT Mon Apr 22 2024

Satellite shows a similar pattern to yesterday with the Monterey Bay
region blanketed in low level stratus and clear conditions
throughout the rest of the Bay Area. Marine layer heights are
similar to yesterday with heights around 1000-1200 feet. For the
Monterey Bay area, stratus looks to dissipate by mid to late
morning. Highs today will be in the mid 70`s to low 80`s inland in
the upper 50`s to lower 60`s along the coast. High temperatures
should run about 1-3 degrees cooler today than they were yesterday.
Today will be the last day with above normal temperatures this week
with below normal temperatures forecast tomorrow through the end of
the work week.

Rest of forecast looks on track with widespread stratus to return
later today and sharp drop in temperatures starting tomorrow.&&

&&

.SHORT TERM...
(Today and tonight)
Issued at 118 AM PDT Mon Apr 22 2024

Mostly sunny conditions are expected inland today with temperatures
expected to warm into the mid 70s to low 80s. Meanwhile, a southerly
surge is likely to occur by late morning or early afternoon which
would limit warming to the upper 50s to mid 60s. As stratus moves
inland, orographic lift is likely to produce widespread drizzle in
coastal regions and in the favored west/southwest facing slopes.
However, precipitation will be light and generally only produce a few
hundredths of an inch.

Coastal drizzle will continue into tonight and early Tuesday morning
with temperatures expected to cool into the mid 40s to low 50s
regionwide. Widespread cloud cover is likely to spread into the
valleys as well (minus the Santa Clara Valley).

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 118 AM PDT Mon Apr 22 2024

Temperatures on Tuesday drop by 10-15 degrees across the interior
with highs generally in the 60s as an upper level low approaches the
region. Coastal drizzle is possible Tuesday night into Wednesday
morning as well with aforementioned low pressure offshore. The low
pressure system will move inland Wednesday night into Thursday
morning with unsettled conditions to persist.

Thursday night into Friday a shortwave trough will move through the
region and bring chances for light rain. Precipitation amounts have
trended downward as of this morning, with only a few hundredths of
an inch expected regionwide. Afternoon temperatures through this
period are forecast to be in the upper 50s to upper 60s with
overnight lows largely in the mid 40s to low 50s. Ever so slight
warming is expected for this upcoming weekend with interior areas
reaching the low 70s with drier conditions returning.

&&

.AVIATION...
(18Z TAFS)
Issued at 1048 AM PDT Mon Apr 22 2024

Mixed bag this morning with stratus impacting Monterey Bay
terminals and VFR elsewhere. Satellite imagery shows a southerly
surge pattern with stratus moving up the coast. The southerly
flow will also usher in stronger winds this afternoon and tonight.
Current taf package has higher winds than previous tafs,
especially for APC and OAK. Did fully buy in on SJC winds, but
some guidance has nearly 20kt SE prevailing winds Tuesday AM. Will
monitor this potential outcome. More widespread stratus tonight
and through the Tuesday AM rush. Didn`t put directly in the tafs,
but drizzle is possible Tuesday AM. Thinning of stratus will occur
most areas 17Z-18Z Tuesday.

Vicinity of SFO...VFR through early tonight. Impact near term
will be gusty SW with potential impact to runway config. Gusts to
20kt, but well short of any AWW criteria. MVFR cigs fill into SF
Bay 06-08Z Tuesday with cigs for SFO by 08Z through 16Z Tuesday.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR cigs continue to thin this AM around
Monterey Bay due to downslope flow from southerly surge. Expecting
VFR this afternoon. Cigs return early for SNS 00Z and then MRY
shortly after 02-04Z. MVFR cigs hold through 18Z Tuesday.

&&

.MARINE...
(Today through Sunday)
Issued at 1048 AM PDT Mon Apr 22 2024

Weakening high pressure to the north has led to weaker northerly
winds over the coastal waters today. Winds are locally strong over
the outer waters north of Point Reyes. Southerly flow will
gradually develop late this afternoon ahead of an approaching low
pressure system. Near Monterey Bay, winds this afternoon may gust
up to about 20 knots, but are expected to diminish into the
evening. Starting Wednesday, winds turn once more to become
moderate and northerly. Larger northwest swell abates through the
day today, with wave heights reducing to around 6 to 7 feet. Light
southerly swell continues to move through the waters this weekend
and through the upcoming work week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...MM
MARINE...MM

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