FXUS66 KMTR 201148
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
348 AM PST Thu Nov 20 2025
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 231 AM PST Thu Nov 20 2025
- Beneficial type rain continues through Thursday.
- Dry weather returns Friday and continues through the weekend.
- Increased risk for sneaker waves and rip currents through
Thursday afternoon through Monday evening.
&&
.SHORT TERM...
Issued at 238 AM PST Thu Nov 20 2025
(Today and tonight)
Active weather overnight, but thankfully not overly impactful. A
digging upper level trough fueled by a phased upper level jet did
lead to cyclogenesis. The resulting surface low is pretty weak
with a surface low currently analyzed just west of the Golden
Gate at 1013 mb. The associated frontal structure is finally
making its way inland. Earlier in the night a few scattered
showers were traversing portions of the Bay Area, but since then
activity has increased in coverage and intensity with the fropa.
Rainfall amounts over the last six hours has generally been a few
hundredths to a few tenths. Jackpot locations include the Marin
Headland with three tenths. Current radar imagery shows the bulk
of the precip is already exiting the Sonoma Co and now heading SE
toward the Central Coast. As such, still expecting morning impacts
to the commute, especially for super commuters. There have been
only a report or two of minor water issues on roadways overnight,
but commuters should still be aware of wet roadways. It's wet, but
thankfully not windy like the last system. A few wind gusts up to
20 mph have been observed.
So, what's the rest of the day look like? The steadier rain will
continue its track S and E with AM impacts. There will be a
brief pause/break in precip behind the front (like the Sonoma
Co), but do expect a few scattered showers this afternoon with the
upper trough moving overhead. Thereafter, a gradually clearing
and drying trend will develop. Temps today will be seasonably
cool.
Depending upon the amount of clearing tonight with decreasing
winds, fog could be an issue over the inland valleys.
&&
.LONG TERM...
Issued at 257 AM PST Thu Nov 20 2025
(Friday through Wednesday)
Mellow extended forecast thanks building high pressure behind the
departing upper level trough/low. A warming and drying trend will
kick off Friday and then continue into next week. Temperatures
will be close to or slightly above seasonal average. Ensemble
guidance keeps the middle of next week on the dry side, which is
good news given the amount of holiday travel expected. Looking
farther down the road, ensembles show some spread with precip
chances returning around the end of the month.
&&
.AVIATION...
(12Z TAFS)
Issued at 348 AM PST Thu Nov 20 2025
Mix of MVFR and VFR conditions across the board with sites
temporarily dropping to IFR as moderate rain moves directly over
airports. Showers continue through early this afternoon before dry
conditions return through the rest of the TAF period. Moderate
confidence that CIGs will clear this afternoon and remain clear
through the rest of the TAF period. Winds initially start more
easterly to southeasterly before switching to northwesterly after
cold frontal passage. Gusty conditions are likely around the time of
frontal passage with winds weakening by tonight.
Vicinity of SFO...MVFR to VFR conditions expected through late this
morning. Light to moderate rain showers continue to move through the
Bay Area with temporary drops in visibility to MVFR-IFR possible as
the heaviest showers move over SFO. Rain chances diminish by this
afternoon with ceiling heights rising. Winds transition from more
southerly to northwesterly with gusts to around 21 knots during the
day.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...MVFR to VFR conditions through the rest of
the morning and into the early afternoon. Ceilings generally rise by
late afternoon/early evening with low confidence in CIGs lowering
overnight. Winds switch from more southerly to northwesterly by the
end of the TAF period with periods of gusty winds expected during
the morning around the time of frontal passage.
&&
.MARINE...
(Today through Tuesday)
Issued at 348 AM PST Thu Nov 20 2025
Hazardous marine conditions return this morning and continue
through the weekend. A weak storm system has arrived, bringing
light rain and moderate to strong winds with strong to near gale
force gusts. Gale force gusts are possible as frontal passage
occurs but, given the speed of the cold front, they are expected
to be short lived with winds diminishing quickly. Winds diminish
by early Friday with moderate northerly winds expected into next
week. Seas build to 10 to 15 feet Thursday and remain elevated
into early next week. Elevated seas will be prolonged by the
arrival of two distinct rounds of long period northwesterly swell.
&&
.BEACHES...
Issued at 322 PM PST Wed Nov 19 2025
A Beach Hazards Statement is in effect from Thursday afternoon
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 from this afternoon through Monday
evening for CAZ006-505-509-529-530.
PZ...Small Craft Advisory until 9 PM PST Friday 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-Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory from 9 AM this morning to 9 PM PST this
evening for Pt Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory until 9 AM PST Friday for Pigeon Pt to Pt
Pinos 0-10 nm.
&&
$$
SHORT TERM...MM
LONG TERM....MM
AVIATION...Kennedy
MARINE...Kennedy
Visit us at www.weather.gov/sanfrancisco
Follow us on Facebook, X, and YouTube at:
www.facebook.com/nwsbayarea
x.com/nwsbayarea
www.youtube.com/nwsbayarea
Prepared by Boulder-Creek.com Weather at: Thu Nov 20 06:30:02 PST 2025
From the National Weather Service
|