229
FXUS66 KSTO 232146
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
246 PM PDT Thu Apr 23 2026


.KEY MESSAGES...

 - Light mountain showers and isolated thunderstorms Friday
   afternoon into early next week.

 - Shower and isolated thunderstorm potential spreads into the
   foothills and into the northern Sacramento Valley for the
   weekend, highest on Sunday.

 - Light showers over the Sierra early to mid-week, south of
   Interstate 80.

 - Temperatures trend cool for weekend, a little above normal mid
   to late next week.

&&

.DISCUSSION...

...Today... Sunny, dry and warmer today. Forecast highs late this
afternoon will be in the 60s to mid 70s in the Valley and
foothills, and in the 50s to 60s in the mountains.

...Friday - Mid Next Week... Ensembles continue to show an upper
low trough building over the eastern Pacific that will move over
the area this weekend as it merges with another trough. This
pattern will introduce chances for light mountain rain and snow
showers starting Friday afternoon, with a 10-15% chance for
isolated thunderstorms over the Sierra crest. There is a better
(15-25% chance) for afternoon/evening mountain thunderstorms over
the weekend, highest on Sunday, with some thunderstorm potential
into the foothills and northern Sacramento Valley. Little to no
impacts are expected as precipitation amounts are generally
anticipated to remain relatively light. Showers and isolated
thunderstorms are expected to be limited mainly to the mountains
Monday. Snow amounts Friday into early next week are expected to
be generally light, a dusting to a few inches.

Lingering showers continue over the Sierra south of Interstate 80
Tuesday into Wednesday.

Gradual cooling is expected into the weekend. Highs will be in
the 60s to 70s in the Valley and foothills, with cooler low to
mid 40s to 50s for the higher elevations. Temperatures trend
higher mid to late week, with 70s to around 80 in the Valley.
elevations

&&

.AVIATION...
VFR conditions with mostly clear skies are expected across
northern CA through 18Z Friday. Surface winds remain under 12 kts
for the next 24 hours. Mountain showers possible after 18Z Friday,
including slight chance of isolated thunderstorms over the Sierra
Crest.

&&

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

$$