FXUS66 KMTR 130008
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
408 PM PST Thu Feb 12 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1211 PM PST Thu Feb 12 2026
- Rain showers taper off by late morning with dry weather
through Friday
- Hazardous beach conditions late Thursday night through early
Saturday morning
- Widespread rain and gustier winds return Saturday and persist
into next week
&&
.SHORT TERM...
Issued at 1211 PM PST Thu Feb 12 2026
(Tonight through Friday Night)
While dry conditions are forecast during the short term, there will
be the potential for pockets of fog. Satellite imagery at this hour
has revealed mostly clear conditions, outside of some developing
stratocumulus due to daytime heating. All in all, it should be a
very pleasant afternoon which is a nice contrast to the last several
days rain.
Observed 72 hour rainfall amounts have ranged from 3-6" across the
Santa Lucia Range, 1-3" across the Santa Cruz Mountains, and 0.25-2"
elsewhere. Northerly 925mb flow of around 15 knots with surface
winds largely under 10 knots in tandem with mostly clear skies
should be sufficient to allow for radiational cooling. If these
winds are a little stronger, however, this may limit cooling and
thus fog production. That said, recent rainfall will contribute to
the overall fog threat. Assuming winds diminish sufficiently and
skies remain clear, additional moisture flux from recent rainfall
will foster fog development. In some spots, fog may reduce
visibility down to 1/4 mile. At this time, the most probable regions
for fog will be across the North Bay, parts of the Santa Clara
Valley, and interior portions of the Central Coast. Regardless of
where you are, be sure to allow for extra driving time on Friday
Morning as sudden changes in visibility may transpire along your
route. Temperatures tonight will also be lower than the past few
days, with some of the aforementioned regions most likely to see
fog dipping down into the mid 30s. If winds really cease, some of
the NBM 10th percentile may verify in spots with temperatures in
the upper 20s. For now, the areal coverage of MinT regions below
the mid 30s precludes the need for any cold weather products, but
it may not be a bad idea to bring in or cover any sensitive
plants and tend to any sensitive animals our crops.
Otherwise, dry conditions are forecast through the day on Friday as
500mb shortwave ridging builds and offshore flow increases slightly
during the day.
&&
.LONG TERM...
Issued at 1211 PM PST Thu Feb 12 2026
(Saturday through next Wednesday)
Late Friday night into early Saturday, low level flow be become more
southerly. As the winds shift, low level wind shear may tend to
keep the boundary layer mixed to keep the areal coverage of fog in
check. As noted above, if winds are stronger (or weaker) than
advertised, the coverage of fog may be less (or more if winds are
weaker).
PoPs re-enter the forecast as early as Saturday mid-morning,
however, there are some caveats associated with this. A compact
upper low is forecast to amplify and move closer to the CA
coastline. As is frequently the case, the upper troughs/lows that
are undergoing amplification will typically be a little slower to
move eastward. NWP for the upcoming weekend seem to be following
this trend with initial forecasts offering broad-brushed PoPs across
much of the Bay Area and Central Coast by 18Z (10AM PST) Saturday,
with the latest precip forecast confining 20 PoP to the western
Sonoma Hills. Hi-res NWP is even less bullish with measurable
rainfall before 18Z Saturday. For now, we'll roll through NBM PoPs
for one more cycle, but alterations may be warranted such that
Saturday is largely rain-free. Saturday MaxT are anticipated to be a
few degrees lower than Friday as cloud cover invades and translates
to filtered sunshine.
Sunday and into early next week will feature a more active weather
pattern. The overall synoptic weather pattern yields high confidence
that widespread rainfall will take shape through the day on Sunday.
Surface cyclogenesis should translate to a tightening of the
MSLP/low-level high gradient. This should allow southerly winds to
increase. 925mb flow ramps up to around 40 knots, especially
along the Pacific Coast which could translate to the potential for
gusty surface winds. The chances for wind gusts to exceed 40 mph
(35 knots) on Sunday are greatest along the Big Sur Coastline,
with probabilities around 70%. Low to medium probabilities
(40-60%) of wind gusts above 40 mph span other Pacific Coast
regions as well as across the higher terrain of the Bay Area and
Central Coast for Sunday and Monday.
With the larger synoptic scale pattern favoring more in the way of
storm systems through our region next week, we'll likely have to
contend with cumulative effects from periods of rainfall. There do
remain some differences with regard to speed and placement of
various systems and this translates to a few scenarios that have
near equal chances of panning out. What we are confident on is that
most if not all areas will see measurable rainfall at some point
next week as even low-end scenarios offer 48 hour QPF ending Tuesday
Evening of 1-2", while the higher end (90th percentile) advertise a
general 3-5" of rainfall with 4-6" across the Coastal ranges.
Because storm systems will likely be occuring within close spatial
proximity to one another, runoff and subsequent flooding may unfold.
We will continue to fine tune messaging as we go through the
weekend, but those across the area should be prepared for rainfall
and potential flood issues as we progress through next week.
Finally, there will be an opportunity for snow across the peaks of
the North Bay Mountains, Santa Lucia Range, and the Gabilan Range
as we progress into next week. A little too early to determine
exact amounts, but snow levels are forecast to drop down below
4,000 feet.
&&
.AVIATION...
(00Z TAFS)
Issued at 407 PM PST Thu Feb 12 2026
Currently VFR at all terminals with cumulus in the higher terrain
beginning to dissipate as the surface low moves off to the southwest
and daytime heating is on the downtrend. Moderate to high confidence
that all terminals will have sub-VFR conditions return tonight. With
ample low-level moisture, light winds, and clear skies, the stage
will be set for radiational cooling. Confidence is high that
ceilings will be low, likely on the cusp of IFR/MVFR. There is a
moderate potential for fog as well, with highest confidence of it
happening within interior valleys.
Vicinity of SFO...Currently VFR with northerly flow. Moderate
confidence on the return of sub-VFR conditions to the terminal
tonight - likely IFR. Diurnal winds will prevail.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Currently VFR with westerly flow at both
terminals. Moderate confidence on the return of sub-VFR conditions
to the terminal tonight - likely on the cusp of IFR to low-end MVFR.
Diurnal winds will prevail.
&&
.MARINE...
(Tonight through next Wednesday)
Issued at 407 PM PST Thu Feb 12 2026
A fresh northerly breeze has returned to the region and will
continue into Friday night. Moderate to rough seas are forecast
Friday into the weekend, with 14 to 18 second period northwest
swell coming through the waters. This will equate to hazardous
boating and near-shore conditions. Southerly winds are then
develop by Saturday afternoon ahead of an approaching frontal
system that is forecast to bring periods of rainfall across the
coastal waters through much of next week.
&&
.BEACHES...
Issued at 943 AM PST Thu Feb 12 2026
Hazardous beach conditions return to the Pacific Coast beaches,
excluding the northern Monterey Bay, Thursday evening and
continue through early Saturday morning. A moderate to long period
swell will arrive late this evening and will result in an
increased risk of sneaker waves and strong rip currents, in
addition to breaking waves of 14 to 19 feet. If you decided to
visit the beach, remember your beach safety tips. Stay off of
jetties, piers, rocks, and other waterside infrastructure. Remain
out of the water to avoid hazardous surf and NEVER turn your back
on the ocean.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement from 10 PM PST this evening through late
Friday night for CAZ006-505-509-530.
PZ...Small Craft Advisory from 9 AM Friday to 3 AM PST Saturday for
Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory until 3 AM PST Saturday for Pt Arena to Pt
Reyes 10-60 NM.
&&
$$
SHORT TERM...Bain
LONG TERM....Bain
AVIATION...Sarment
MARINE...RGass
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Prepared by Boulder-Creek.com Weather at: Thu Feb 12 20:30:02 PST 2026
From the National Weather Service
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