875
FXUS66 KMTR 140541
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1041 PM PDT Mon May 13 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1217 PM PDT Mon May 13 2024

Relatively quiet pattern persists through the forecast period with
morning marine stratus and clear skies elsewhere. Inland
temperatures warm into the 70s and 80s each afternoon with a
persistent marine layer keeping coastal highs in the 60s.

&&

.UPDATE...
Issued at 903 PM PDT Mon May 13 2024

Did a few minor tweaks to the forecast this evening to cool
temperatures by a few degrees across the interior for tomorrow. This
is as the past couple of days did not reach our actual forecast
temperatures for inland areas. Low clouds will penetrate well inland
into the valleys overnight and begin to mix out by mid-to-late
morning. With the marine layer sitting at around 1,600-1,800 feet
per the Fort Ord Profiler, temperatures tomorrow afternoon will
likely reach the mid 70`s to mid 80`s in far inland areas with 60`s
near the coast.

&&

.SHORT TERM...
(This evening through Tuesday)
Issued at 1217 PM PDT Mon May 13 2024

A weak upper low continues to slowly traverse into the southwest
US while gradually deepening our marine layer. The main result of
this will be a slightly greater extent of marine stratus inland.
However, the overall pattern continues to be dominated by a stout
longwave ridge over the Eastern Pacific, so afternoons will be
clear across the area with stratus lingering along coastal areas.
Afternoon highs in the 70s for most and 60s along the coast.
Farther inland locations such as southern Monterey county eastern
Contra Costa county, and northern Napa counties will see highs in
the mid-to-upper 80s.

&&

.LONG TERM...
(Tuesday night through next Sunday)
Issued at 1217 PM PDT Mon May 13 2024

Through midweek, the ridge pattern strengthens slightly as the
weak upper low pulls away. Though the ridge influence will be
dominant, we remain on the periphery, so there is no strong signal
for a pronounced warming trend through the week. Instead,
afternoon highs will increase just by a few degrees from midweek
into the weekend. Most areas will see the mid-70s with inland
locations in the lower 80s. A few of the aforementioned warmest
locations have a shot at hitting the 90 degree mark. Lows will
generally be in the lower to mid 50s. Coastal clouds are likely
during the overnight and AM hours with a gradual clearing towards
the coast each afternoon.

&&

.AVIATION...
(06Z TAFS)
Issued at 1038 PM PDT Mon May 13 2024

Currently seeing a mix of VFR-LIFR at the terminals. The marine
layer continues to be allowed to deepen thanks to a weak upper-
level low with the depth somewhere in the 1,500-1,800 foot range.
This deeper marine layer will allow for stratus to penetrate
further inland and impact all terminals within the TAF period.
Highest confidence is in IFR-low-end MVFR at LVK, MRY, SFO, SJC,
and SNS and LIFR at APC and STS. OAK has the greatest uncertainty
as to whether or not the ceiling will be IFR or LIFR; while not
high, highest confidence is in IFR based on persistence and a
deepening marine layer, but the terminal`s proximity to APC could
allow for the terminal to go LIFR. Widespread VFR and breezy
onshore flow will prevail by tomorrow afternoon.

Vicinity of SFO...Currently VFR with breezy westerly flow. An IFR-
low-end MVFR ceiling will impact the terminal again overnight with
conditions improving to VFR by late-morning. Winds will remain
onshore and breezy through the TAF period with gusts up to 25
knots to be expected tomorrow afternoon.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently IFR with westerly flow at MRY and
MVFR with northwesterly flow at SNS. Confidence is highest in
ceilings remaining IFR-low-end MVFR overnight. VFR to prevail by the
afternoon. Winds will remain onshore through the TAF period. MRY
quickly deteriorates again tomorrow evening with SNS looking to
deteriorate into the next TAF cycle.

&&

.MARINE...
(Tonight through next Sunday)
Issued at 1038 PM PDT Mon May 13 2024

  Moderate to fresh northwesterly winds continue through the
middle of  the work week before diminishing to gentle to moderate
beginning  Wednesday. Occasional near gale force to gale force
gusts are  possible across portions of the northern outer waters
overnight  Monday into Tuesday morning. Winds will become more
west to  southwesterly and gusts are expected to strengthen across
the  northern outer waters heading into the late week and weekend.
Overcast conditions and widespread stratus continue across the
coastal waters as surface high pressure builds. Significant wave
heights across the central and northern outer waters will build to
10-14 feet by mid- week before seas diminish by late week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT Tuesday for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Sarment
MARINE...Kennedy

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