FXUS66 KMTR 281204
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
404 AM PST Fri Nov 28 2025
...New AVIATION, MARINE, BEACHES...
.KEY MESSAGES...
Updated at 101 AM PST Fri Nov 28 2025
- Pattern change beings milder temperatures today
- Stratus mixes out through the morning, lingering at the coast
and in the far interior East Bay
- No major changes in the forecast weather through the next week
&&
.SHORT TERM...
Issued at 101 AM PST Fri Nov 28 2025
(Today and tonight)
Satellite imagery shows high-level clouds over the Bay Area,
associated with a weakening frontal boundary that is moving across
the state. Stratus decks are also visible across the North and East
Bay valleys and parts of eastern San Mateo County and the Santa
Clara Valley. The stratus decks will stay in place through sunrise
and for a couple of hours afterward, with some areas remaining
socked in through the day, but the upper level disruption of the
passing front may be enough to keep the widespread dense fog away
this morning. In the event that patchy dense fog does form, drivers
should slow down, use low beam headlights, and leave extra space
between them and the car in front.
Today marks a transition period between the departure of the ridge
that has brought us seasonally warm weather these last few days and
the development of a very strong ridge over the Gulf of Alaska which
will promote downstreams troughs into the contiguous 48 states. The
daytime should feature sunny skies for most people, with lingering
stratus possible in areas of eastern Contra Costa and Alameda
counties connected to the Central Valley, in addition to western
parts of San Francisco and San Mateo Counties. High temperatures
today will range from the upper 50s to the middle 60s across most of
the Bay Area, the middle 60s to lower 70s across inland parts of the
Central Coast, and the lower to middle 50s across the highest
mountain peaks and ridgelines. These high temperatures may need to
be adjusted downward if stratus lingers longer than expected across
a place.
&&
.LONG TERM...
Issued at 101 AM PST Fri Nov 28 2025
(Saturday through Thursday)
It might be the day after Thanksgiving but the weather pattern might
make some people recall Groundhog Day. There will be a couple of
troughs digging into the Intermountain West but these will remain
displaced too far east to give us any significant concerns. For our
region, the next week should feature a rather persistent forecast
light offshore flows, seasonally mild temperatures, and dry and
clear skies, which should help eat away at the pool of stratus that
has developed across the Central Valley.
There is a very slight chance (10-15% probability at most) of light
precipitation towards the latter part of next week if one of the
troughs digging into the Intermountain West deepens into a cutoff
low that retrogrades over southern California and merges with a
second cutoff low coming in off the coast, but the probabilities
are so low and the nuances numerous enough that the forecast
remains highly uncertain. CPC outlooks for December 5 to 11
features a slight lean towards precipitation totals above seasonal
averages for the Central Coast, but the key word here is slight
with the CPC putting the probabilities around 33-40%. For context,
the seasonal average rainfall total for Salinas Airport for that
period comes in at just under half an inch.
&&
.AVIATION...
(12Z TAFS)
Issued at 404 AM PST Fri Nov 28 2025
Areas of LIFR-IFR in fog and low stratus continues to redevelop
early this morning. A cooler air intrusion is arriving from the
northwest which will gradually weaken the lower level thermal
ridge aloft i.e. weakening the lower level temperature inversion
(this is the cap on fog and stratus). The weakening of the lower
level temperature inversion should help preclude widespread
development of dense fog (visibility less than 1/4 mile) in our
forecast area, though we'll still have low IFR ceilings and
visibilities to navigate through. In theory conditions like we
have this morning should help vertical mixing winds get underway a
little sooner along with some help from what we can get from
diurnal warming under a late November sun. Best probability of VFR
will be in the afternoon. HREF shows areas of fog and stratus
/LIFR-IFR/ redeveloping tonight and Saturday morning.
Vicinity of SFO...IFR due to stratus continues to 18z today. VFR
forecast from late morning through afternoon and evening. IFR due
to stratus redevelops tonight and Saturday morning. Light and
variable wind becoming northwest 8 to 14 knots later this morning
and during the afternoon. Light and variable wind tonight and
Saturday morning.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...High clouds on satellite are obscuring
the areal coverage of fog/stratus over the coastal waters. Low to
moderate confidence current VFR conditions continue through the
morning. IFR ceilings possible tonight and Saturday morning. Winds
mainly southeasterly 5 to 10 knots this morning, becoming onshore
5 to 10 knots in the afternoon. Winds light southeasterly tonight
and Saturday morning.
&&
.MARINE...
(Today through Wednesday)
Issued at 338 AM PST Fri Nov 28 2025
Light to moderate northerly winds continue today as a weak cool
front moves through the northern waters. Localized fresh winds are
expected south of Point Pinos tonight into Saturday. Winds will
decrease early Saturday before increasing late Saturday into early
next week. Hazardous marine conditions return midweek as a cut-off
low moves through the coastal waters with winds increasing and
wave heights building due to incoming long period westerly swell.
&&
.BEACHES...
Issued at 338 AM PST Fri Nov 28 2025
Moderate to 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. A beach hazards statement is in
effect for the coastline from Sonoma County to Monterey County
through 10 PM PST Sunday evening. 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 Sunday evening for CAZ006-505-
509-529-530.
PZ...Small Craft Advisory from 9 AM this morning to 9 PM PST this
evening for Pt Pinos to Pt Piedras Blancas 0-10 nm.
&&
$$
SHORT TERM...DialH
LONG TERM....DialH
AVIATION...Canepa
MARINE...Canepa
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Prepared by Boulder-Creek.com Weather at: Fri Nov 28 08:30:02 PST 2025
From the National Weather Service
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