107
FXUS66 KSTO 302008
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
108 PM PDT Tue Sep 30 2025

For additional details on weather and expected impacts over the
next 7 days, please visit weather.gov/sto/briefing.

.SYNOPSIS...
Cooler temperatures continue today with scattered rain showers
across interior NorCal through tonight; highest chances within
the Coastal Range, southern Cascades, and northern Sierra. Drier
and warmer conditions heading into next weekend with chances for
breezy northerly winds.

&&

.KEY MESSAGES...

*  TODAY THROUGH WEDNESDAY:

 - Low pressure continues its trek through the area today,
   bringing chances this afternoon, evening, and overnight for
   areas of wetting rain. Highest totals will be over the
   mountains.

 - This afternoon and evening also sees a 10-20% chance for
   isolated thunderstorms, primarily along the Sierra Crest and in
   Shasta County.

 - Scattered showers will linger on Wednesday, with a general drying
   trend beginning in the afternoon.

* THURSDAY THROUGH MONDAY:

 - Chances for lingering showers on Thursday morning have mostly
   dissipated at this point, though thunderstorm chances have
   increased for Thursday afternoon and evening

 - Thunderstorm chances on Thursday have increased to 10-30%,
   primarily remaining in Shasta County and the Sierra Crest south
   of I-80. Non-zero chance for thunderstorms to continue
   overnight into Friday. 10-20% chance for isolated thunderstorms
   along the Sierra Crest on Friday afternoon and evening.

 - Friday sees a return to mostly dry weather and a slight warming
   trend into the weekend. Daytime highs will reach closer to
   normal through early next week.

 - Breezy northerly winds expected periodically Friday through
   Sunday, strongest on Sunday.

.AVIATION...
VFR to MVFR conditions in the Sac Valley due to frontal system
moving through today and Wednesday. Showers and isolated
thunderstorms possible in the northern Sacramento Valley. Ceilings
will decrease to MVFR in the Sacramento Valley again Wednesday
morning, around 17z. Further south, VFR conditions expected to
prevail. Onshore flow expected to continue, with gusts up to 25
kts across the Sacramento Valley through 00z Wednesday, lingering
in the northern Sacramento Valley, northeastern foothills, and
southern Cascades through about 06z. Elsewhere, winds remain at or
below 12 kts.

&&

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

&&

$$