FXUS66 KMTR 160517
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
917 PM PST Sun Feb 15 2026

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 110 PM PST Sun Feb 15 2026

 - Rain continues today and continues this week as additional 
   storm systems arrive

 - Strong winds through mid-week; Wind Advisory for the Central
   Coast Monday

 - A Coastal Flood Advisory is in effect through Tuesday for minor 
   high tide flooding

 - Winter Weather Advisory Monday through Wednesday Central Coast
   Mts with accumulating snow

 - Much colder with mountain snow mid to late week

&&

.UPDATE...
Issued at 604 PM PST Sun Feb 15 2026

The rain has been steady in the North Bay, but has recently moved 
into the rest of the Bay Area in a more organized fashion. Rain 
totals so far are generally less than 0.5"; outside of roughly 1"
in the Santa Rosa Area, the Santa Cruz Mountains, and the Santa 
Lucia Mountains; and up to 2" in the coastal North Bay mountains. 
That's more or less on track with the forecast. Since the system 
is moving so slowly, many locations have waited all day for the 
onset of steady rain. On the other hand, the slow speed is keeping
a long rain duration as as the rain will linger through the night
and well into Monday morning. The 00Z sounding didn't yield very 
impressive measurements for instability this evening. Despite good
low level lapse rates, the MLCAPE is only 33 J/kg, less than the 
35 J/kg of MLCIN. We did have a decent 16 kts of 0-1 km shear. 
High shear, low CAPE environments have historically proven to be 
tornado producers, but the CAPE is probably too low, and the 
current radar presentation looks fairly well behaved for now. I 
don't think it's going to happen during this shift. A thunderstorm
here or there is still possible, but the instability will fall 
off with the setting sun. If anything does spin up, CAMS are 
indicating the best chance for rotation is around 8-10 PM. The big
question in the forecast remains how strong the low will be 
tomorrow, and when and where it will make landfall. Somewhere 
between Monterey County and San Mateo County seems likely, with 
the latest trends bringing the strongest winds and heaviest to the
coastal mountains surrounding Big Sur. Cut-off lows are like 
Plinko chips though. It's really hard to predict where they will 
end up. By Monday evening the rain will likely transition to 
isolated showers in the cold, post frontal environment before the 
reinforcing front moves through Tuesday.

&&

.SHORT TERM...
Issued at 150 PM PST Sun Feb 15 2026
(This evening through Monday)

An occluded area of low pressure remains parked off the NorCal
coast this afternoon. The "business" side of the surface low
continues to produce rain, heavy showers, an occasional rumble of
thunder over the waters, and gusty winds. Rainfall amounts over 
the last 12 hours shows less than a tenth across the interior 
locations and a 0.10-0.50 coastal mountains and locally up to 
1.00 inch North Bay coast. Winds have generally been gusting 25-35
mph with local gusts 50-60 mph. Strongest winds so far have been 
Point Reyes and N Bay Interior Mts.

The next 12-24 hours will get real interesting as the longwave
pattern and associated meso-scale features become more clear.
Yesterday I mentioned the offshore low getting a boost from some
upper level jet features. Well, today's CAMS show the cyclogenesis
really tapping into the upper level jet. Today's guidance shows a 
cyclonic curved jet max rounding the base of the upper low off 
the coast late tonight and Monday. The left exit region of this 
curved jet will take aim at the Central Coast. Some guidance puts
the focus more northward, but most keep it closer to Monterey 
Bay. This set up is a prime example to foster rapid cyclogenesis.
Not a "bomb", but rapid nonetheless. Latest HRRR/HREF/WRF models 
drop the surface low to 995-ish mb. The newly deepened low will 
drift NE into the CEntral Valley following the path of the jet max
overhead Monday and Monday night. This rapid deepening will 
facilitate very strong winds, heavy rain, and potential for 
tstorms. For the wind, didn't go all in as time/strength due to 
lower confidence, but felt enough confidence to issue a Wind Adv 
for the Central Coast. Highest peaks could see gusts up to 60 mph.
Areas outside of the Wind Adv will still be windy, similar to 
today. As for thunderstorms, SPC still has the Central Coast in a 
Marginal risk. The combo of moisture, daytime heating, jet 
dynamics, and cold air aloft filtering in will allow for a few 
stronger storms. Given some weak shear will need to monitor for 
any rotating cells. Speaking of colder air aloft, the air mass 
will cool behind the low dropping snow levels across the region to
less than 5k. Therefore, some high elevation snow will be 
possible over the Santa Lucia and Gabilan Ranges. Issued a Winter 
Wx Advisory for area above 3k feet beginning Monday afternoon 
continuing through Wednesday.

&&

.LONG TERM...
Issued at 240 PM PST Sun Feb 15 2026 
(Monday night through next Saturday)

The surface low continues to pull NE while another boundary
arrives from the N Monday night into Tuesday. There maybe a brief
lull in precip before another round of steadier precip arrives
Tuesday and Tuesday night. Precip will ease once again early
Wednesday before ramping back up with a third system late in the 
week. Lastest guidance from our hydro partners keeps our mainstem 
rivers in check with less than 10% for flooding, but urban/small 
stream issues will likely build through out the week as more rain
piles up. Rainfall totals Tue/Wed: 0.50-1.0 inches most areas and
1.0-2.5 inches Santa Cruz Mts/Santa Lucia Mts. More rain 
Thurs/Sat: most areas 0.25-0.75 inches and locally 1.0-1.5 inches
Santa Cruz Mts/Santa Lucia Mts. The subsequent system will also 
usher in much colder air with dropping snow levels. The bulk of 
the snow accumulation for the Winter Wx Adv will accumulate during
this timeframe Tue/Wed. Especially the mts above Big Sur with 20 
inches with in the realm of possibility. While the N and E Bay 
arean't in the Winter Wx Adv at the moment they'll likely see a 
few inches of snow. Given the lowering trend of snow levels would
not be surprised to see minor accumulations along the Santa 
Cruz/Santa Clara county line above 2000 feet. Not buying off on it
just yet, but for the snow lovers out there some guidance really 
drops snow levels across the N Bay later in the week with a few 
wet flakes below 1500 feet. Stay tuned for that. 

In addition to precip we'll be holding onto gusty winds too.
Instead of being focused over the Central Coast they'll become
more widespread. May need to think about Wind Adv later in the
week, but conf isn't high enough yet to issue it. The combo of
wind and snow over the higher peaks will make for poor conditions
with potential vsby issues and trees burdened by snow coming 
down. 

Lastly, while snow levels drop it goes with out saying that
overnight lows will drop. The combo of cold overnight lows
Wednesday through Friday will lead to dangerous conditions for 
those without adequate shelter. A mixture of Cold Wx and Extreme 
Cold products will likely be issued with temperatures in the upper
20s and 30s.

&&

.AVIATION...
(06Z TAFS)
Issued at 917 PM PST Sun Feb 15 2026

Generally MVFR to low end VFR with mid- to high level clouds across 
the region as the main rain band crosses the Bay Area and Central 
Coast. Southerly winds will abate in the wake of the main rain band 
with scattered showers possible overnight. Early Monday morning and 
beyond, high resolution models are showing possible cyclogenesis 
near the coast and heading across the Bay Area and Central Coast, 
making the forecast rather uncertain, especially for wind speed and 
direction, through Monday afternoon. The general trend is for the 
winds to shift towards the northwest through the day on Monday, 
remaining strong and breezy with widespread gusts of 20-30 kt while 
widespread rain continues in addition to a small, but nonzero, 
chance for thunderstorms. Rain chances should diminish on Monday 
evening ahead of another storm system expected to arrive after the 
end of the 24-hour TAF period.

Vicinity of SFO... Generally MVFR-low end VFR conditions at the 
terminal. Gentle southeast winds will continue overnight, with low 
to moderate confidence in winds turning northeast on Monday morning. 
A developing small-scale low makes the forecast for Monday 
uncertain, but in general expect a shift to a strong and breezy 
northwest wind through Monday with rain showers continuing through 
Monday afternoon. Some high resolution model data has the next 
system arriving at the terminal area close to the end of the TAF 
period, but confidence is too low to include this in the current 
forecast.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals... MVFR to low end VFR across the region and 
through the TAF period. Breezy south winds, especially at SNS, 
continue through the next couple of hours as the main rain band 
passes through with IFR conditions possible in the strongest 
showers. Potential cyclogenesis near Monterey Bay early Monday 
morning makes the TAF forecast uncertain beyond around 15Z, with a 
general shift to a more westerly wind with strong wind gusts at the 
terminals before winds and rain chances decrease in the evening.

&&

.MARINE...
(Tonight through next Saturday)
Issued at 917 PM PST Sun Feb 15 2026

A band of intense rain with embedded thunderstorms is moving
through the inner coastal waters with building southerly winds,
with light showers behind the band. Strong southerly winds
continue along the inner coastal waters south of Monterey Bay, but
winds will abate elsewhere tonight, especially across the waters
north of Pigeon Point, before rebuilding into a strong northwest
breeze on Monday. Stronger winds are likely to last through
midweek as a high westerly swell arrives. Rough to very rough seas
will prevail across the coastal waters through the
week.Thunderstorm chances increase behind the initial front and
linger through  Tuesday.

&&

.BEACHES...
Issued at 556 PM PST Sat Feb 14 2026

The combination of spring tides and storm surge will bring minor
high tide flooding to the San Francisco Bay and Monterey Bay
through Tuesday. Up to 1.0 ft of inundation is expected in the 
San Francisco Bay, with up to 1.5 ft in the Monterey Bay. At the 
San Francisco tidal gauge, high tide is expected to at 9:34 AM 
Sunday, 10:16 AM Monday, and 10:58 AM Tuesday. High tide timing 
varies up to 90 minutes earlier or later along the Pacific Coast 
and throughout the San Francisco Bay, respectively.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 3 PM PST Tuesday for CAZ006-506-508-
     529-530.

     Wind Advisory from 8 AM to 8 PM PST Monday for CAZ516>518-528-
     530.

     Winter Weather Advisory from 4 PM Monday to 4 PM PST Wednesday 
     for CAZ517-518.

PZ...Small Craft Advisory from 3 PM Monday to 3 AM PST Tuesday for 
     Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-
     SF Bay N of Bay Bridge.

     Small Craft Advisory until 3 AM PST Tuesday for Mry Bay-Pigeon 
     Pt to Pt Pinos 0-10 nm.

     Small Craft Advisory from 9 AM to 9 PM PST Monday for Pt Reyes 
     to Pigeon Pt 0-10 nm.

     Gale Warning from 9 PM Monday to 3 AM PST Tuesday for Pt Reyes 
     to Pigeon Pt 0-10 nm.

     Gale Warning until 9 PM PST Monday for Pt Pinos to Pt Piedras 
     Blancas 0-10 nm.

     Small Craft Advisory from 9 AM to 3 PM PST Monday for Pt Arena 
     to Pt Reyes 10-60 NM.

     Gale Warning from 3 PM Monday to 3 AM PST Tuesday for Pt Arena 
     to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...MM
LONG TERM....MM
AVIATION...DialH
MARINE...DialH

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Prepared by Boulder-Creek.com Weather at: Sun Feb 15 22:30:03 PST 2026