FXUS66 KMTR 220912
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
112 AM PST Sat Nov 22 2025
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 111 AM PST Sat Nov 22 2025
- Benign weather conditions continue through the middle of the
week
- Coastal stratus returns tonight, but clear during the daytime
- Pattern change arrives after Thanksgiving, with details highly
unclear
&&
.SHORT TERM...
Issued at 111 AM PST Sat Nov 22 2025
(Today and tonight)
The skies remain clear so far tonight with some assistance from
light offshore flow stemming from the interaction between an upper
level low centered off the coast of Baja California and a building
ridging pattern coming in behind it. Radiative fog development is
possible tonight in the inland valleys, including Sonoma County and
the interior portions of Contra Costa County, any fog that develops
should dissipate rather quickly after sunrise. High temperatures
today should range in the middle to upper 60s in the inland valleys,
to the upper 50s and the lower 60s along the Pacific coast. This
evening, a marine layer should redevelop and bring stratus back to
the immediate coastal areas, although the developing upper-level
ridge should keep the marine layer rather compressed and inland
stratus development unlikely.
&&
.LONG TERM...
Issued at 111 AM PST Sat Nov 22 2025
(Sunday through Friday)
Wash, rinse, and repeat for the next couple days, as the mild ridge
persists over the West Coast and gives us similar conditions on
Sunday and Monday, maybe a couple degrees cooler in the Bay Area as
onshore flow strengthens. The ridge then builds into the
Thanksgiving holiday, keeping fair conditions in the forecast and
raising temperatures around a few degrees by Thanksgiving, which
might end up being the warmest day of the 7-day forecast.
There hasn't been much change in the prognosis in the pattern change
coming towards the end of the week as an upper level trough
approaches the western United States. The forecast uncertainty
remains very high, with "boom" scenarios of a prolific rainfall
and "bust" scenarios of no appreciable precipitation and light
offshore winds are still in play. As the previous forecaster
noted, confidence that there will be *a* storm system in the
western United States is high, exemplified by a high- amplitude
ridge over the eastern Pacific into Alaska and northwestern
Canada, but confidence on where it will set up and its impacts to
the region remain low. One other thing to mention is that with the
upcoming Thanksgiving weekend, even if the most impactful effects
from this system do miss the Bay Area and Central Coast,
potential holiday travel plans may be impacted, particularly for
those heading out east for the extended holiday. Stay tuned to the
forecast updates over the next several days, as we refine what
exactly is going to happen with this system.
&&
.AVIATION...
(06Z TAFS)
Issued at 914 PM PST Fri Nov 21 2025
Dry weather supports ongoing high confidence VFR forecast for the
evening. For tonight and Saturday morning VFR continues at most
terminals, however longer night-time radiative cooling hours and
residual boundary layer humidity may combine to produce fog
patches, possibly including dense fog /VLIFR-IFR/. The WMC-SFO
pressure gradient and nocturnal cool/cold air drainage winds
support east to southeast winds which may also transport dense
tule fog from the Central Valley to portions of the East Bay late
tonight and Saturday morning. Patchy morning fog Saturday,
otherwise VFR.
Vicinity of SFO...VFR. Mainly light and variable wind tonight and
Saturday morning, becoming west 5 to 10 knots Saturday afternoon
and evening.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. Winds becoming light southeast
tonight and Saturday morning then west near 10 knots Saturday
afternoon and early evening.
&&
.MARINE...
(Tonight through next Thursday)
Issued at 902 PM PST Fri Nov 21 2025
A high pressure system will build in from the northwest through
early next week. While winds diminish, hazardous marine conditions
will continue into the weekend as seas will remain moderate.
Elevated seas will be prolonged by the arrival of long period
northwesterly swell.
&&
.BEACHES...
Issued at 919 AM PST Fri Nov 21 2025
A Beach Hazards Statement is in effect through Monday evening. A
long period northwesterly swell will result in an increased risk
for sneaker waves and rip currents. Breaking waves of 13 to 18
feet are expected. Sneaker waves can unexpectedly run
significantly farther up the beach than normal, including over
rocks and jetties. Rip currents are typically more frequent and
stronger in the vicinity of jetties, inlets, and piers.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Monday evening for CAZ006-505-
509-529-530.
PZ...Small Craft Advisory until 3 AM PST Sunday for Pigeon Pt to Pt
Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt
Reyes 10-60 NM.
&&
$$
SHORT TERM...DialH
LONG TERM....DialH
AVIATION...Canepa
MARINE...Canepa
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Prepared by Boulder-Creek.com Weather at: Sat Nov 22 02:30:03 PST 2025
From the National Weather Service
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