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000
FXUS66 KMTR 201751
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1051 AM PDT Sat Apr 20 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 247 AM PDT Sat Apr 20 2024

Slight warming trend across the interior through Monday with
diminishing marine influences near the coast. Potential
drizzle/light rain chances mid-to-late next week.

&&

.UPDATE...
Issued at 838 AM PDT Sat Apr 20 2024

Morning satellite imagery definitely has a summer esque vibe to
it. Shallow marine layer has led to stratus along portions of the
coastal waters and much of the inland valleys this morning. Fort
Ord/Bodega Bay profilers and KOAK sounding put the depth closer to
1200-1400 feet. Interesting to note that stratus is a little more
broken up around SF Bay, which is likely due to passing mid-high
level clouds overhead. These clouds may be limiting the amount of
cooling at the top of the marine layer and thus disrupting the
stratus deck. Similar to summer the marine layer/stratus deck will
linger through 10 AM before giving way to sunshine. As noted
below temps this afternoon will top out in the upper 70s to lower
80s in the warmest inland locations. Given the time of year these
temperatures will yield minor Heat Risk concerns. Regardless, if
you have outdoor plans today wear sunscreen and have adequate
hydration.

No update needed...

&&

.SHORT TERM...
(Today and tonight)
Issued at 247 AM PDT Sat Apr 20 2024

Expecting patchy coastal drizzle in the favored upslope regions
this morning with conditions improving by late morning. This is as
the marine layer remains around 1,000 feet in depth and will mix
out by the afternoon. Inland temperatures are expected to reach
the mid-to- upper 70s with coastal areas in the low 60s to low 70s
this afternoon. Winds will be on the increase by this afternoon
and will become breezy with northwest gusts between 25-35 mph near
the coast, the coastal hills, and higher peaks across the region.
Overnight, temperatures will largely cool into the upper 40s to
lower 50s.

&&

.LONG TERM...
(Sunday through Friday)
Issued at 247 AM PDT Sat Apr 20 2024

Sunday and Monday will continue to be warm inland with
temperatures more likely to reach the lower 80s across the
interior. Meanwhile, coastal areas will peak in the low 60s to low
70s as the marine influence begins to diminish. By Tuesday,
conditions cool as a well- advertised upper level low approaches
and moves through the region. Cooler, unsettled weather will
continue through late week with increased cloud cover and
potential for light rainfall. Most likely scenario will be drizzle
near the coast and in the hills with possible light rain
elsewhere.

&&

.AVIATION...
(18Z TAFS)
Issued at 1050 AM PDT Sat Apr 20 2024

Stratus has dissipated for most stations with only SNS reporting non-
VFR conditions still. Satellite shows stratus dissipating over SNS
with clearing expected by 1830Z at the latest. Confidence in stratus
returning tonight remains low. Moderate winds and lower RH values
will both be limiting factors for stratus development. Currently
expecting MVFR CIGs at OAK, MRY, and SNS overnight due to lighter
wind speeds and slightly higher RH values. Low confidence but
guidance does suggest LIFR may be possible for MRY and SNS during
the early morning hours. Moderate westerly to northwesterly winds
expected during the day with lighter, more variable winds expected
overnight.

Vicinity of SFO...VFR through the TAF period with gusty winds
possible this afternoon. Guidance hints that MVFR CIGs may become
more likely overnight but moderate westerly winds will help keep the
atmosphere more well mixed and inhibit stratus development. Winds
will weaken slightly during the late morning before moderate
westerly winds return mid afternoon.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR transitioning to MVFR overnight. CIGs
continue to linger at SNS with satellite showing full dissipation
should occur within the next 30-45 minutes. Low to moderate
confidence that stratus will develop overnight. By early morning,
breezy westerly to northwesterly winds weaken slightly but RH values
are relatively high (80-90%) giving a little more confidence to
include BKN MVFR CIGs. Similar to today, stratus will dissipate
towards the end of the TAF period in the late morning.


&&

.MARINE...
(Today through Thursday)
Issued at 1050 AM PDT Sat Apr 20 2024

Northerly winds build into the afternoon today to become fresh to
strong across much of the waters through early Monday morning with
near gale force gusts possible. Gale force gusts are expected
over the far northern outer waters in this same time period, but
begin to diminish late Sunday night. Northwest swell builds Sunday
as gusty conditions continue but looks to diminish towards the
middle part of the 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 from 3 PM this afternoon to 9 PM PDT this
     evening for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm-Pt Reyes
     to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 9 PM PDT Sunday for Pt Arena to Pt
     Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Sunday
     for Pt Arena to Pt Reyes 10-60 NM.

     Gale Warning from 3 AM to 9 PM PDT Sunday for Pt Arena to Pt
     Reyes 10-60 NM.

     Small Craft Advisory from 3 PM this afternoon to 9 PM PDT Sunday
     for Pigeon Pt to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Kennedy
MARINE...Kennedy

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