313
FXUS66 KSTO 222126
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
126 PM PST Thu Jan 22 2026

.KEY MESSAGES...

 - Valley low clouds/fog potential through Friday morning.

 - Fog potential diminishes Saturday-Sunday as north to northeast
   winds increase Friday night into Saturday. Strongest gusts
   over the mountains.

 - Dry weather prevails this weekend, followed by renewed fog
   potential early next week.

&&

.DISCUSSION...

...Today Through Friday...

Current GOES-West satellite imagery shows diminishing fog and low
clouds across the Valley this afternoon with scattered mid to
high level clouds aloft as an upper low begins it`s path across
southern California.

We allowed the Dense Fog Advisory to expire at noon, although
patchy areas of fog still persist across the Valley. Fog chances
return tonight into tomorrow morning. Probabilities for
visibilities 0.5 mile or less are 60 to 80% from the central
Sacramento Valley and southward, with the highest probabilities in
the southern Sacramento Valley. Remember to use low-beam
headlights when driving through fog, exercise caution, and slow
down.

As northerly winds increase Friday afternoon, any fog present
should quickly diminish. Strongest winds won`t occur until
Saturday, but breezy winds will be present Friday afternoon and
evening along the western side of the Sacramento Valley, and in
the mountains.

...Friday - Early Next Week...

The upper low will trek across southern California over the
weekend, weakening the upper level ridge and initiating an
offshore flow pattern. As a result, north to northeast winds
continue to increase on Saturday. The strongest winds are
expected over the Sierra and along the western portion of the
Sacramento Valley (I-5 and westward) where probabilities of gusts
greater than 30 mph are 60 to 80%. Relative humidities trend
lower over the weekend as well, primarily over the mountains,
foothills, and northern Sacramento Valley. No precipitation is
expected with this weekend`s system.

Conditions for widespread fog are less favorable through the
weekend as a result of these north to northeast winds. However, as
ridging builds back in early next week the potential for Valley
low clouds/fog returns.

&&

.AVIATION...
Lingering patchy MVFR/IFR conditions in central/southern
Sacramento Valley, Delta, and northern San Joaquin Valley through
22-23z Thursday. FG/BR expected to re-develop after 03z-06z Friday
with similar aerial extent as today except coverage may extend
into the northern Sacramento Valley. Surface winds will be below
12 kts. Increasing north-east winds after 03z Friday, with gusts
15-25 kts across portions of the northern Sacramento Valley and up
to 30 kts over the mountains.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$