332
FXUS66 KSTO 262143
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
143 PM PST Mon Jan 26 2026

.KEY MESSAGES...

 - Areas of dense fog in the Valley and lower foothills tonight
   into Tuesday morning

 - Slight chances for light showers mid week and again over the
   weekend mainly north of Interstate 80. Little to no impacts
   expected.

&&

.DISCUSSION...

...Today through Tuesday Morning...
The region remains under upper level ridging today, with dry
weather prevailing across the area. For tonight into Tuesday
morning, high resolution ensemble guidance indicates a 40 to 65
percent chance of visibilities less than 1/2 mile in the
central/southern Sacramento Valley, and the northern San Joaquin
Valley. A Dense Fog Advisory has been issued for the central/southern
Sacramento Valley and northern San Joaquin Valley from 10 PM
tonight through 11 AM PST Tuesday. Be sure to slow down and use
low- beam headlights if fog is encountered while driving.

...Tuesday Afternoon through the Weekend...
By Tuesday afternoon, chances for light rain and snow showers
return to the area and continue into early Wednesday morning,
mainly from Interstate 80 northward as an upper level trough
deepens over the Eastern Pacific Ocean. Latest WPC precipitation
guidance indicates amounts ranging from 0.01-0.30 inches; highest
over the northern mountains. Upper level ridging then looks to
build back in for the late week timeframe with dry weather and
morning fog. Ensemble guidance then indicates the potential for
another system to approach the Pacific Northwest by the weekend
with some additional chances for light precipitation once again
mainly north of Interstate 80 over the mountains. Little to no
impacts are expected from either system as forecast precipitation
amounts are fairly light.

&&

.AVIATION...
General VFR conditions for much of interior NorCal except for
patchy MVFR/IFR/LIFR conditions in fog and mist from 05Z-19Z
Tuesday in the Valley, with best chances from Sacramento
southward. Surface winds generally below 10 kts through 20z
Tuesday, when Valley wind gusts will increase up to 15 kts and
foothill and mountain gusts will wincrease up to 25 kts through
06z Wednesday.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory from 10 PM this evening to 11 AM PST Tuesday
for Central Sacramento Valley-Northern San Joaquin Valley-
Southern Sacramento Valley.

&&

$$