217
FXUS66 KMTR 231945
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1245 PM PDT Thu May 23 2024

...New SHORT TERM, LONG TERM...

.SYNOPSIS...
Issued at 1225 PM PDT Wed May 22 2024

Summer-like pattern to persist through Thursday. Temperatures are
forecast to dip below seasonal averages this weekend as an upper
level trough impacts the region. Temperatures begin to warm Sunday
through the next week.

&&

.SHORT TERM...
(This evening through Friday)
Issued at 1244 PM PDT Thu May 23 2024

The sun is shining over our area, as satellite shows clear skies
over our area. Soundings show that there has been some drier air
that moved over our region and helped diminish the marine clouds.
Some patches of clouds are expected to return tonight near the Bay
Area, with moments of lower clouds near Monterey Bay and Salinas
similar to this morning. Minimum temperatures tonight will drop
overall in the 40s with isolated areas of low 50s. Maximum
temperatures will drop significantly compared to today (between
5-8 degree drop). Inland areas will see within the 60s with higher
elevations seeing up to low to mid 70s. Coastal areas will see
temperatures in the 50s. Minimum relative humidity will also
increase on Friday, indicating some moisture will be pulled in
from the onshore breeze.

&&

.LONG TERM...
(Friday night through next Wednesday)
Issued at 1244 PM PDT Thu May 23 2024

The low pressure system centered over Washington and Oregon, will
continue to dip south a bit, which will enhance and influence some
of the cooling trend over our area. Ensemble models still
indicate that temperatures will drop to cooler than normal high
temperatures with majority of our region seeing high 50s to low to
mid 60s on Saturday. Temperatures overnight will remain
relatively consistent through the weekend with minimum
temperatures in the 40s to low 50s. Tuesday night may start to see
a slight warm up in overnight temperatures with minimums in the
50s across most of the area. Cluster models also have been in
somewhat of an agreement of precipitation Friday going into
Saturday as some onshore flow pushes some of the marine moisture
near the coast. Chances for precipitation will be 5-10% for less
than a tenth of a inch along the coast, which will likely be in
the form of drizzle and will cause little to no impacts.

As the trough moves off to the east, the ECMWF and GFS show
agreement of a broad, weak ridge beginning to build on Sunday into
Monday. This will bring some warmer temperatures for the week,
especially in the interior regions, with max temperatures in the
high 70s and low 80s. With this weak upper level pattern change,
models do not show a strong offshore signal, which will allow for a
onshore breezy to continue. This will cause coastal regions to only
warm up a bit, with temperatures in the high 50s to mid 60s.

&&

.AVIATION...
(18Z TAFS)
Issued at 1024 AM PDT Thu May 23 2024

Currently VFR at all terminals with sparse stratus coverage in the
Monterey Bay and along the Big Sur Coast. Moderate confidence of VFR
through the TAF period at all terminals with the exception of the
Monterey Bay terminals of MRY and SNS. Low clouds in the range of
FL015-FL035 could impact the terminals of LVK, OAK, SFO, and SJC
overnight; however, confidence was not high enough at this time
to include as a definitive ceiling.

Vicinity of SFO...Currently VFR with breezy northwesterly flow. VFR
through the TAF period. Winds will transition to become westerly
with gusts up to 30 knots to be expected this afternoon and evening.
Low confidence in the development of an MVFR ceiling, but low clouds
in the range of FL030-FL050 will be present by the early morning
hours and linger through the end of the TAF period.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR with northwesterly flow at
both terminals. Moderate confidence that MVFR stratus will return to
both terminals overnight. Winds will remain breezy out of the west
through the TAF period.

&&

.MARINE...
(Today through Tuesday)
Issued at 1024 AM PDT Thu May 23 2024

Building surface high pressure over the Eastern Pacific Ocean will
allow for strong northwesterly winds to prevail for one more day
today, with gale force gusts across the outer coastal waters.
Expect  hazardous conditions and steeper wind waves as a result.
Northwesterly winds diminish and significant wave heights abate
heading into the weekend as surface high pressure over the Eastern
Pacific Ocean weakens and retrogrades to the west and a troughing
pattern evolves.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay.

     Small Craft Advisory until 3 PM PDT this afternoon for Pt Arena
     to Pt Reyes 0-10 nm.

     Gale Warning until 9 PM PDT this evening for Pt Arena to Pt
     Reyes 0-10 nm.

     Small Craft Advisory until 3 PM PDT Friday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 3 AM PDT Friday for Pigeon Pt to Pt
     Pinos 0-10 nm.

     Small Craft Advisory from 9 AM to 3 PM PDT Friday for Pigeon Pt
     to Pt Pinos 0-10 nm.

     Gale Warning until 3 AM PDT Friday for Pt Arena to Pt Reyes 10-
     60 NM.

     Gale Warning until 9 PM PDT this evening for Pigeon Pt to Pt
     Pinos 10-60 NM.

&&

$$

SHORT TERM...SO
LONG TERM....SO
AVIATION...Sarment
MARINE...Sarment

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