922
FXUS66 KMTR 131130
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
430 AM PDT Mon May 13 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1208 AM PDT Mon May 13 2024

A relatively quiet pattern will persist featuring overnight and
morning coastal clouds with clear skies elsewhere. Inland
temperatures will warm into the 70s and 80s each afternoon with
cool onshore breezes keeping coastal temperatures in the 60s.

&&

.SHORT TERM...
(Today and tonight)
Issued at 1208 AM PDT Mon May 13 2024

A weak upper low will drift towards the central CA coast while
upstream ridging dominates the northeast Pacific. This pattern will
promote the subsequent deepening of the marine layer today as low
stratus clouds penetrate deeper inland. The top of the marine
inversion has continued to increase, and is now up to around 2,000
feet per the Fort Ord profiler. Given this depth wouldn`t be
surprised to see a little coastal drizzle early this morning in the
favorable spots so added this to the forecast. Any accumulations
should be quite minor. Otherwise look for low clouds to clear back
towards the coast this afternoon with the marine influence keeping
coastal/bayside temperatures in the 60s. Elsewhere look for 70s and
80s in the warmest inland valleys, with a few locations in southern
Monterey County perhaps nearing 90 degrees. Clouds will push back
inland by this evening with mostly cloudy conditions again
prevailing for many areas tonight. Lows will dip into the upper 40s

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 1208 AM PDT Mon May 13 2024

Temperatures will cool slightly with onshore flow and weak troughing
aloft persisting. An upper ridge does build/strengthen over the
northeast Pacific by mid week, but it appears our area will remain
along its periphery with no strong signal for a warming trend. In
general high temperatures will range from the 60s along the coast to
the lower-mid 80s for the warmest inland areas. This will only
produce a minor HeatRisk for the warmest locations. 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...
(12Z TAFS)
Issued at 430 AM PDT Mon May 13 2024

Currently seeing a mix of VFR-LIFR at the terminals. The marine
layer is overall on a deepening trend with the depth currently at
about 1,800 feet according to the Fort Ord Profiler; however, it did
experience a few hours of compression between the 06Z TAF issuance
and this one. LIFR-MVFR conditions are slated to return to all
terminals except LVK tonight. Ceiling heights will be highly
dependent on the evolution of the marine layer between now and then.
Widespread VFR and breezy onshore flow will prevail by this
afternoon.

Vicinity of SFO...Currently IFR with breezy westerly flow. High-end
IFR-low-end MVFR stratus will continue to impact the terminal
through the late morning. Winds will remain onshore and breezy
through the TAF period. Confidence is low on what exactly the
terminal will see overnight in terms of ceiling height due to the
lack of model/guidance consensus and a finicky marine layer. The
outcome is highly dependent on the evolution of the marine layer
between now and then, but current thinking is that the terminal will
see a ceiling and it will likely be low-end MVFR-high-end IFR again.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently LIFR with westerly flow at both
terminals. Conditions will briefly improve to VFR by the afternoon
with a quick return to LIFR this evening for MRY and IFR tonight for
SNS. Westerly/northwesterly winds will prevail through the TAF period.

&&

.MARINE...
(Today through Saturday)
Issued at 430 AM PDT Mon May 13 2024

Fair weather will prevail through the week as surface high
pressure  over the Eastern Pacific Ocean builds and moves east.
Fresh  northwesterly breezes will prevail Monday and Tuesday
before winds  begin to diminish mid-week. Significant wave heights
will continue  to build to 12-15 feet by Tuesday before gradually
abating through  the rest of 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-Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory until 9 AM PDT Tuesday for Pt Arena to Pt
     Reyes 10-60 NM.

     Small Craft Advisory from 9 PM this evening to 9 AM PDT Tuesday
     for Pigeon Pt to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...SPM
LONG TERM....SPM
AVIATION...Sarment
MARINE...Sarment

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