FXUS66 KMTR 250134
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
534 PM PST Mon Nov 24 2025
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 144 PM PST Mon Nov 24 2025
- Dry and mild this week
- Cooler temperatures this weekend as the next system approaches
- Confidence increasing for gusty offshore winds by the end of the
upcoming weekend
&&
.SHORT TERM...
Issued at 144 PM PST Mon Nov 24 2025
(This evening through Tuesday)
A mid/upper level ridge is building into the region from the
southwest and will result in a gradual warming trend through
Wednesday or Thursday. As such, temperatures this afternoon will
warm into the 60s across inland areas while upper 50s are expected
near the coast. Overnight, we are expecting less cloud cover and fog
than the previous days as weak offshore flow persist in the higher
elevations across the region and will work to compress the marine
layer. However, cannot rule out patchy dense fog in the North Bay
valleys in responds to drainage flow in the Russian River valley
and East Bay valleys as tule fog spills in from the Central Valley.
Temperatures overnight are likely to range from the 40s across the
interior and lower 50s near the coast.
The warming trend will continue on Tuesday with the warmest interior
spots in the southern Santa Clara Valley, Hollister Valley, and
interior Central Coast reaching up to around 70 degrees F.
&&
.LONG TERM...
Issued at 144 PM PST Mon Nov 24 2025
(Tuesday night through next Sunday)
Wednesday and/or Thursday will be the warmest days of the week as
the aforementioned ridge continues to build aloft. This is when we
are expecting lower 70s in the Santa Clara Valley, Hollister Valley,
and interior Central Coast under mostly sunny skies. These
temperatures will be up to 10 degrees above seasonal averages.
From the previous forecaster: "Towards Friday into the upcoming
weekend, a pattern change will occur as the ridge over the western
United States breaks down, and one amplifies upstream across the
Gulf of Alaska. As a result, cold Arctic air descends into the
Mountain West and Central Plains states. Ensemble model guidance
continues to point to this system following more of an inside slider
like development in our region. In other words, the impacts of this
trough fall into the windy and dry side rather than the rainy side.
Still too early to tell how strong the impacts will be and where the
greatest threats will occur, but the current forecast has a period
of gusty offshore winds developing across the Bay Area and Central
Coast late Saturday through, and somewhat beyond, the end of the 7-
day forecast period. Confidence in the exact nature of the impacts
will improve through the rest of the week, so keep in touch with the
forecast updates for the most up to date information."
&&
.AVIATION...
(00Z TAFS)
Issued at 534 PM PST Mon Nov 24 2025
It's mainly VFR along with a few areas of hazy conditions late
this afternoon. Our forecast area is bookended by a shallow cool
front and air mass moving southward over the coastal waters and
low ceilings, fog and tule fog slowly advancing back close to our
easternmost area of responsibility bordering our neighboring WFOs
Sacramento and Hanford forecast areas. A stable air mass including
a lower precipitable water (0.52") on the 00z (4 pm) Oakland upper
air sounding compared to 0.72" 12z (4 am) this morning favors
improving radiative cooling tonight and Tuesday morning. Light
offshore winds per SAC-SFO 0.9 mb and WMC-SFO 2.0 mb both support
a reversal of maritime influence we had over the weekend (which
helped limit dense fog coverage), with an increasing continental
influence reaching into our forecast area, including a tule fog
intrusion from the east tonight and Tuesday morning; so far not
seeing any numerical weather prediction mesoscale models showing
any significant boundaries forecast to disrupt the light offshore
wind pattern Tuesday morning which may allow any fog intrusion to
the Bay Area to linger during the day, minus incoming solar heating
Tuesday e.g. this may favor a positive feedback loop set up for
Tuesday night/Wednesday morning.
Vicinity of SFO...VFR continuing through the evening is supported
by 24 hour trends warmer temp and lower relative humidity compared
to this time yesterday. SF Peninsula is free from stratus clouds at
this time per satellite imagery. There's an increasing probability
20%-30% of IFR per recent HREF between 09z-16z Tuesday, for the
time being tempo IFR ceiling is noted 13z-17z Tuesday, but caveat
is persistent light NE-E wind may transport even lower conditions
to VLIFR-LIFR during this time. It's a low confidence forecast
since it's still many hours from now, however weather conditions
and the time of year (plus recent generous early season rain) are
all favorable for aforementioned conditions and it needs to be
closely monitored. As such, it is a low confidence forecast as to
the return and duration of VFR Tuesday, if the model forecasts are
under-forecasting the extent of fog it may take longer to mix out
to VFR than currently 17z advertised in the TAF.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Moderate to high confidence VFR continues
through at least mid evening here, with 24 hour trends neutral to
slightly milder while humidities are essentially unchanged. Current
satellite imagery also supports VFR forecast to mid evening. Nocturnal
radiative cooling will set up cool air drainage winds for tonight
and Tuesday morning, providing a mixing wind to help prevent the
development of stratus and/or fog. Low to moderate confidence VFR
continues tonight and Tuesday. Cool front and air mass passes by
to our west, HREF/HRRR model ouput show dry, cool air drainage
mixing winds and VFR prevailing tonight and Tuesday morning. VFR
continues Tuesday afternoon with winds gently shifting back to
light onshore in the mid to late afternoon.
&&
.MARINE...
(Tonight through next Sunday)
Issued at 436 PM PST Mon Nov 24 2025
The swell will continue to subside over the next couple days as
high pressure brings favorable conditions across the area. Winds
will begin to increase again late week, building moderate to rough
seas.
&&
.BEACHES...
Issued at 614 PM PST Sun Nov 23 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 until 10 PM PST this evening for CAZ006-
505-509-529-530.
PZ...None.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Canepa
MARINE...Canepa
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Prepared by Boulder-Creek.com Weather at: Mon Nov 24 18:30:02 PST 2025
From the National Weather Service
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