318
FXUS66 KSTO 302120
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
120 PM PST Fri Jan 30 2026



.KEY MESSAGES...

 - Dry weather with patchy fog in the Valley and lower foothills
   expected through Saturday.

 - Precipitation chances continue to trend down for Sunday into
   early Monday morning.

&&

.DISCUSSION...

...Today Through Saturday...
Ridging continues to dominate the synoptic pattern, yielding to
dry and temperate weather across the area today through Saturday.
The potential for widespread dense fog returns tonight into
tomorrow morning with current guidance indicating a 50 to 80%
chance of visibilities less than 1/2 mile across the Delta,
central/southern Sacramento Valley, and northern San Joaquin
Valley. As such a Dense Fog Advisory is in effect from midnight to
12 pm PST Saturday for the aforementioned areas. Be sure to slow
down and use low-beam headlights if fog is encountered while
driving. A gradual warming trend is forecast into Saturday, with
Valley highs in the 60s. Winds will be generally light, with
periods of breezy offshore flow.

...Sunday through Early Monday Morning...
Upper level ridging will begin to breakdown as an upper low
approaches the region. Ensemble guidance indicates the potential
for this weak system to bring very light precipitation to the
Coast Range and Shasta County by late weekend into early Monday
morning. Guidance continues to trend drier, but light
precipitation chances remain nonzero.


...Early Next Week...
Ridging builds back in, with dry and warmer weather anticipated
across interior NorCal along with morning fog potential. The
Climate Prediction Center continues to favor drier and warmer
than normal conditions into early February. Otherwise, breezy
offshore flow is expected at times.

&&

.AVIATION...
Lingering MVFR conditions this afternoon mainly in the northern
San Joaquin Valley from BR/HZ, elsewhere VFR conditions through
around 03z Saturday. BR/FG to develop in the central/southern
Sacramento Valley, Delta, and northern San Joaquin Valley
resulting in IFR/LIFR conditions through around 20z Saturday.
Surface winds below 12 kts across the region.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory from midnight tonight to noon PST Saturday
for Carquinez Strait and Delta-Central Sacramento Valley-
Northern San Joaquin Valley-Southern Sacramento Valley.

&&

$$