FXUS66 KMTR 080929
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
129 AM PST Sun Feb 8 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 126 AM PST Sun Feb 8 2026
- Patchy fog this morning, especially for North Bay Valleys.
- 20 to 40% chance of rain in the North Bay tonight.
- Chances for soaking rain Tuesday night into Wednesday, and
again next weekend
&&
.SHORT TERM...
Issued at 126 AM PST Sun Feb 8 2026
(Today through Monday)
Mostly clear skies are being observed across the Bay Area and the
Central Coast this morning. As temperatures cool and reduce dew
point depressions, fog is starting to develop being patchy in
nature from the East Bay Valleys down the Salinas Valley and more
areas of fog development in the North Bay Valleys. Widespread
dense fog is not expected, but webcams will be monitored through
the morning.
After daybreak, the added sunshine will help mix out any
lingering fog my mid morning. Partly cloudy skies will remain out
ahead of the next system to the North, but mostly sunny skies are
expected for areas south of the Bay Bridge. Temperatures will
increase into the mid 60s for the Bay Area (upper 50s to low 60s
along the coastline) and a chance for low 70s in southern Monterey
County. No major changes to the forecast regarding the rain
chances today. The shortwave trough is still expected to pass over
southern Oregon keeping the higher precipitation totals there and
in the northern California. The (20 to 40 percent) chance for
area in the forecast area will mainly be in the North Bay with
only a couple hundredths or rain possible late this afternoon and
evening. Any chance for a sprinkle south of the North Bay is less
than 10 percent.
Cooler air will filter in behind this wave. Temperatures tomorrow
morning will be a degree or two cooler than this morning, with
another chance for patchy fog. Similarly, high temperatures will
also be slightly cooler on Monday than today, but still remain a
couple degrees warmer than seasonable norms. No precipitation is
expected to start the work week.
&&
.LONG TERM...
Issued at 126 AM PST Sun Feb 8 2026
(Monday Night through Saturday)
The next upper level low will drop southward over the ocean and
move over the California Coast Tuesday afternoon through
Wednesday. Model runs are trending wetter with this system
compared to earlier in the weekend. With precipitable water
amounts trending just under an inch, there is a good chance that
coastal areas could see about or just over a half an inch of rain,
with some coastal higher elevations around an inch. While there
will still be a difference in amounts with coastal areas seeing
more, traditional rain shadowed areas could still even receive
over a quarter of an inch of rain. Lastly, models are suggesting a
potent 120+kt 300 mb jet will company this upper level low
providing some synoptic lift enhancement. However, the Euro is
suggesting the core of the jet would arrive over the Central Coast
whereas the GFS is slightly more north toward the Bay Area. While
CAPE values are not overly robust, model sounding are showing a
strip of shallow, skinny area of instability. While confidence is
not high, there is a slight chance for thunder Tuesday night.
While the details may still be tweaked, it looks like a widespread
soaking rain is in store for the Bay Area and the Central Coast
midweek.
Cooler air advection with this upper level low will help provide
more seasonable normal temperatures across the area by the middle
of the week. Weak ridging is expected Thursday in to Friday for a
brief respite from the rain.
Models are showing fairly good agreement in another system
expected to move in over the weekend. While models are disagreeing
on the specific timing and strength of the system, many ensemble
members are suggesting that this system has a higher chance for a
widespread soaking rain than the midweek system. And with colder
air filtering in aloft, snow levels are expected to drop below
5,000 feet. How low they will go and whether or not the peaks of
some of the higher terrain could see a dusting remains uncertain.
But morning low temperatures this weekend could drop down below 40
degrees for some of the interior valley locations.
&&
.AVIATION...
(06Z TAFS)
Issued at 943 PM PST Sat Feb 7 2026
So far this evening, stratus has largely remained off the coast,
with only localized development south of STS and pockets along
the SF Peninsula. However, confidence remains high that marine
stratus under onshore flow will move inland late tonight into
Sunday morning. This will be a later onset than last night in many
areas. IFR ceilings should be the dominant mode, but some areas
of LIFR and fog will also develop. Fog is most likely near
STS/APC. Conditions should improve by Sunday afternoon with a
return to mainly VFR conditions. A weakening frontal boundary will
bring increased mid level clouds on Sunday, lowering during the
evening. Light showers are expected along the North Bay coast with
only sprinkles elsewhere. MVFR/IFR ceilings are expected Sunday
night with this weak front. Light NW to variable winds overnight,
then W to NW on Sunday.
Vicinity of SFO...Patches of stratus have been observed on
satellite/webcams north of the terminal, but have shown little
inland progress. Marine stratus will expand along the coast
overnight, impacting the terminal Sunday morning. IFR conditions
due to low ceilings are expected, but can't rule out brief LIFR,
along with reductions in visibility from mist. Should see
improving conditions by 20-21Z on Sunday. MVFR or IFR conditions
should return Sunday night as the weak front moves through. Winds
will mainly be WNW around 10 kts or less.
SFO Bridge Approach...Similar to SFO.
Vicinity of SJC and OAK...Marine stratus will make its way into SF
Bay overnight, reaching the terminals around 09-13Z. IFR ceilings
are expected, but a low chance of LIFR stratus or fog also exists.
conditions improving around 18-19Z at SJC and 20-21Z at OAK. Low
clouds returning Sunday night. Variable winds overnight, then
light NW Sunday afternoon.
Monterey Bay Terminals...Mainly VFR overnight, with potential for
IFR/LIFR low stratus or fog developing early Sunday morning.
Winds variable overnight, returning to NW Sunday afternoon. Low
clouds returning Sunday night.
&&
.MARINE...
(Tonight through next Friday)
Issued at 943 PM PST Sat Feb 7 2026
Generally light to gentle north to northwest winds across the
waters persist through the weekend, with light west and southwest
winds across the norther outer waters through Sunday. Generally
moderate seas continue through Sunday. Moderate north winds off
the Big Sur coast will strengthen to a fresh to strong breeze
Sunday into early Monday. Winds continue to strengthen and seas
build for most of the waters Monday into Tuesday.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 9 AM PST Monday
for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory from 3 AM to 9 PM PST Monday for Pt Arena
to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...DK
LONG TERM....DK
AVIATION...Tangen
MARINE...DialH
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: Sun Feb 8 02:30:03 PST 2026
From the National Weather Service
|