FXUS66 KMTR 172351
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
351 PM PST Sat Jan 17 2026
...New AVIATION...
.KEY MESSAGES...
Updated at 1240 PM PST Sat Jan 17 2026
- Dry weather, cool mornings, and warm afternoons persist into
early in the week
- Morning fog across the delta and interior North and East Bay
Valleys
&&
.SHORT TERM...
Issued at 1240 PM PST Sat Jan 17 2026
(This evening through Sunday)
Not much change this afternoon, similar to yesterday with fog
lingering in the interior East Bay Valleys and the West Delta.
The most notable difference, is that we have high clouds moving
from south to north across the region. We will continue to watch
closely how these high clouds will affect afternoon temperatures,
but largely should still be another warm day across much of the
region this afternoon with high temperatures in the mid 60s to mid
70s (up to 80 degrees F in the higher terrain).
Tonight, look for fog (dense at times) to develop across the West
Delta, North Bay Valleys, and interior East Bay Valleys that will
linger into Sunday morning. Again, high clouds may limit overnight
cooling by a few degrees making the fog forecast difficult. Offshore
winds are forecast to decrease over the next 36 hours or so, and may
allow for more cooling in the higher elevation tonight.
Looking for a near repeat for Sunday afternoon as high clouds will
continue to stream across the region. Thus, temperatures will be
similar to Saturday afternoon.
&&
.LONG TERM...
Issued at 1240 PM PST Sat Jan 17 2026
(Sunday night through next Friday)
Little change in the long term forecast as a mid/upper level ridge
of high pressure will remain in place just off of the West Coast
through midweek. Thus, look for similar conditions as this weekend
to persist. Late night and early morning fog across the West Delta,
North Bay Valleys, and interior East Bay Valleys looks like a good
possibility.
By late week, there is a potential weak short wave trough forecast
to impact the region with chances for light rainfall Friday into
Saturday. However, it is looking the region may just see an increase
in cloud cover and return of cooler conditions (closer to seasonal
averages). It isn't until late January we see the Climate Prediction
Center show the region leaning above normal in their 8-14 Day
Precipitation Outlook.
&&
.AVIATION...
(00Z TAFS)
Issued at 351 PM PST Sat Jan 17 2026
Satellite shows high clouds over the region, with any
signs of low cloud or fog found east of us and in the Valley.
Observations across the region depict VFR conditions with primarily
light winds at the terminals. Expect this to generally continue
through the evening hours for most sites. The question for tonight
will be, does the high cloud limit fog development? Current thinking
is that the North Bay terminals should see some conditions falter,
especially at KSTS given their pattern the past week. For KAPC the
and East Bay terminals, confidence is moderate to low given last
night's reports and high clouds remaining in the forecast. Trended
closer to MVFR to VFR conditions for these sites, should they see
any fog development; however we'll need to keep an eye on them.
Tomorrow, any fog that does develop should clear by mid to late
morning, with VFR conditions returning and high clouds lingering.
Vicinity of SFO...Quiet and VFR conditions, plus light offshore
winds continue for much of the TAF cycle. Winds may go variable for
a bit overnight but return to the east-northeast by tomorrow
morning.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR conditions continue through the period.
KSNS should hold with offshore flow through this period, while KMRY
observes onshore flow for the next few hours before becoming
offshore once again.
&&
.MARINE...
(Today through Thursday)
Issued at 837 AM PST Sat Jan 17 2026
Moderate to breezy northeast winds continue across the San Pablo
Bay, the delta, and through the Golden Gate through the weekend
while light northeast to north winds persist across the rest of
the coastal waters. Light seas continue into early next week
before the next round of long period swell arrives and brings
light to moderate seas in the mid week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...KR
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: Sat Jan 17 18:30:03 PST 2026
From the National Weather Service
|