FXUS66 KMTR 090909
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
109 AM PST Mon Feb 9 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 109 AM PST Mon Feb 9 2026
- Patchy fog this morning.
- Wetting rains expected Tuesday morning through Wednesday and
again next weekend. &&
.SHORT TERM...
Issued at 109 AM PST Mon Feb 9 2026
(Today and tonight)
As a very weak front exits the area to the southeast, surface
observations are showing winds becoming more northwesterly (except
for a few localized terrain differences). With increased mid and
upper level moisture, mostly cloudy to overcast skies are expected
through daybreak. This cloud deck and light winds around 5 mph
should help suppress radiational fog development. However, patchy
fog is still possible through daybreak this morning in the more
traditional spots that are more sheltered from the wind. At the
time, no advisory is expected, but will be monitored through the
morning.
As zonal flow aloft sets up today, conditions should be fairly
quiet. Temperatures are once again expected to climb into the 60s
with coastal areas remaining in the low 60s (or even upper 50s).
With increasing moisture aloft ahead of the next system, cloud
cover will remain keeping low chances for any fog development
overnight into Tuesday morning. Temperatures will drop down to the
low 50s along the coast and mid 40s for inland areas (with a
chance of localized low 40s for far interior locations).
An upper level is expected to move from the north Central Pacific
toward southern California today, inducing surface cyclogenesis
out over the ocean this afternoon. Models are showing fairly good
agreement that that surface low is expected to move toward Point
Conception before taking a left turn tomorrow morning and head
toward the Bay Area. It is this low that is expected to bring the
widespread soaking rain to the area. While the rain shadow will be
in effect, models continue to trend wetter with this low allowing
most of the area to get something though there is still some
uncertainty on exact amounts as this system starts to come into
the range of high res guidance. But with decent forcing, a strong
low level jet in the afternoon and orographic lift, the coastal
areas will likely sees the highest rain totals. Rain rates could
be up to 0.25" per hour in many of the stronger cells, with
localized rates up to 0.50" per hour closer to the center of the
low. Lastly, while instability is not overly strong, isolated
thunder cannot be completely ruled out in the late afternoon and
into Tuesday evening.
&&
.LONG TERM...
Issued at 109 AM PST Mon Feb 9 2026
(Tuesday through Sunday)
There is still some disagreement in model guidance on the exact
trend for the low, but most guidance as the low stalling out over
the ocean just west of the Golden Gate and weakening Tuesday night
through Wednesday. Rain will be come more scattered at times
overnight into Wednesday with breaks developing. That being said,
it looks Wednesday could be another wet day. With models still
disagreeing with the track and trend for the low, there is lower
confidence in the exact end time and could vary north to south
across the forecast area, as well as coastal vs. inland. But there
is a non-zero chance that light rain lingers through Thursday
morning, but impacts should be minimal. Lastly, cooler air is
expected to advect in behind the low. Temperatures will finally
return back to seasonal normals with highs in the 50s (maybe touch
low 60s?) and lows in the 40s.
Weak ridging Thursday into Friday morning should offer a brief
respite from the rain. However, Models are still suggesting
another upper level trough will move over the Bay Area and the
Central Coast. This trough is a much larger wave from a spatial
extent, which opens the door for smaller embedded waves to move
over the area setting up a pattern that trends towards rain being
a common theme for the extended forecast. At this distance, it is
hard to have confidence on the timing of not just the rain, but
any breaks in the rain, but it looks wet from Saturday onward.
Additionally, this system moving in overnight Friday into Saturday
is projected to have a colder airmass associated with it.
Freezing levels will lower opening the door for some snow
potentially at higher elevations. But even sheltered valley
locations are expected to have morning low temperatures in the mid
to upper 30s by early next week.
&&
.AVIATION...
(06Z TAFS)
Issued at 940 PM PST Sun Feb 8 2026
Low ceilings will continue overnight as a weak front passes
through the area. Showers and patchy drizzle associated with the
front have largely ended. MVFR, with local IFR conditions near
the coast, are expected overnight into Monday morning. Winds will
turn northerly overnight into Monday, bringing drier air into the
area. This should erode stratus earlier than previous days, with
gradual improvement from north to south and most sites returning
to VFR by 14-18Z. Light northerly flow should prevent the return
of stratus through Monday evening, although a switch to southerly
winds along the coast Tuesday morning could bring stratus back
into coastal areas. Winds light N-NW or variable through Monday.
Vicinity of SFO...Mainly MVFR conditions overnight, but periods of
IFR late this evening as stratus continues to move inland.
Conditions improving Monday morning, with clearing to VFR
anticpated 14-18Z. Light N-NE winds may keep stratus banked along
the terrain to the southwest before it clears. VFR should prevail
through Monday night. Winds light NW overnight, becoming N on
Monday.
SFO Bridge Approach...Similar to SFO, except clearing may occur an
hour or two earlier as N-NE winds push stratus to the southwest
and bank up along the terrain.
Vicinity of SJC and OAK...Mainly MVFR conditions overnight, except
IFR late this evening at OAK. Brief reductions to IFR overnight at
SJC/OAK are possible with low cloud layers lingering around SF
Bay. Conditions improve early Monday morning (around 13-17Z). Fog
potential is lower tonight than previous nights. Winds light
variable to N-NW.
Monterey Bay Terminals...Confidence has increased that IFR/MVFR
ceilings will persist over MRY/SNS overnight. Conditions gradually
improve Monday morning, clearing to VFR by 16-18Z. May see a
return of stratus late Monday night or Tuesday morning. Winds
light NW to variable.
&&
.MARINE...
(Tonight through next Saturday)
Issued at 940 PM PST Sun Feb 8 2026
A cold front will continue to move southeastward over the coastal
waters and bays overnight through early Monday. Northwest winds
will strengthen to a fresh to strong breeze today into Monday. A
low pressure system will then approach from the west bringing rain
to the coastal waters and bays Tuesday through Wednesday. Rain
chances return next weekend.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM Tuesday to 3 AM PST Wednesday for
Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory until 9 PM PST this evening for Pt Pinos to
Pt Piedras Blancas 0-10 nm.
Small Craft Advisory from 9 AM Tuesday to 9 AM PST Wednesday for
Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 3 AM PST Tuesday for Pt Arena to Pt
Reyes 10-60 NM.
Small Craft Advisory from 9 PM Tuesday to 9 AM PST Wednesday for
Pt Arena to Pt Reyes 10-60 NM.
Small Craft Advisory until 3 PM PST this afternoon for Pigeon Pt
to Pt Pinos 10-60 NM.
Small Craft Advisory from 3 PM Tuesday to 9 AM PST Wednesday for
Pigeon Pt to Pt Pinos 10-60 NM.
&&
$$
SHORT TERM...DK
LONG TERM....DK
AVIATION...Tangen
MARINE...Soulat
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Prepared by Boulder-Creek.com Weather at: Mon Feb 9 02:30:03 PST 2026
From the National Weather Service
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