438
FXUS66 KMTR 202356
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
456 PM PDT Fri Sep 20 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 143 PM PDT Fri Sep 20 2024

Warming trend continues through the weekend into early next week,
with moderate HeatRisk possible inland Monday and Tuesday.

&&

.SHORT TERM...
(This evening through Saturday)
Issued at 143 PM PDT Fri Sep 20 2024

A warming trend was expected to start today as an upper level low
moves off to the east, but you wouldn`t know it from the 24 hour
temperature trends, which have not shown much warming from the same
time yesterday, and if anything, have ran up to five degrees cooler
across the valleys. The extensive stratus deck this morning and the
continuing onshore flow may have kept things cooler than what was
earlier forecast. Have bumped today`s high temperatures across the
inland valleys down to account for this. The current forecast calls
for high temperatures today to rise into the upper 70s to the lower
80s across the inland valleys, around the mid 60s to the mid 70s
along the Bayshore, and into the upper 50s to mid 60s along the
Pacific coast. Some more warming is expected tomorrow with the
warmest inland regions scraping into the low 90s.

Stratus has retreated back to the coastal regions and the Monterey
Bay region, where the clouds are expected to persist through the day
before the stratus extends inland this evening and overnight.

&&

.LONG TERM...
(Saturday night through next Thursday)
Issued at 143 PM PDT Fri Sep 20 2024

The fringes of an upper level ridge will impact the state through
the weekend into early next week, with the main impact being a
warming trend across the region. By the early part of next week,
high temperatures should peak into the mid to upper 90s across the
inland valleys and the upper 60s to the mid 70s across the Pacific
coast. Model ensemble clusters continue to show poor consensus on
the upper level pattern towards the rest of the next week. However,
CPC outlooks suggest a lean towards temperatures above seasonal
averages and precipitation below seasonal averages into the first
several days of October.

&&

.AVIATION...
(00Z TAFS)
Issued at 454 PM PDT Fri Sep 20 2024

Currently VFR everywhere except the Monterey Bay terminals of MRY
and SNS which are enveloped in ceilings. Largely a persistence
forecast as the marine layer is similar to what it was 24 hours ago
at 2,000 feet and is expected to remain in that range through the
TAF period. High confidence in the blanket of stratus offshore
filtering inland, impacting all terminals tonight in the form of
ceilings with the exception of LVK which is expected to remain VFR.
Widespread VFR will prevail by tomorrow afternoon.

Vicinity of SFO...Currently VFR with westnorthwesterly flow. High
confidence in a ceiling impacting the terminal overnight and through
most of the morning tomorrow, the ceiling will be on the MVFR/IFR
cusp.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently IFR with westerly flow at MRY and
MVFR with northwesterly flow at SNS. High confidence in SNS further
deteriorating to IFR early this evening with both terminals
becoming VFR by tomorrow afternoon.

&&

.MARINE...
(Tonight through next Wednesday)
Issued at 454 PM PDT Fri Sep 20 2024

Winds continue to be fresh out of the northwest through Monday,
with stronger gusts over the far northern waters. Seas will
continue to build through the weekend, with wave heights up to 13
feet in the far northern outer waters as large, and shorter period
northwesterly swell continues to move into the waters. Seas begin
to abate Tuesday through the end of the forecast period.

&&

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

&&

$$

SHORT TERM...DialH
LONG TERM....DialH
AVIATION...Sarment
MARINE...AC

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