633
FXUS66 KSTO 042044
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
144 PM PDT Fri Sep 4 2026

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


.KEY MESSAGES...

  - Lingering showers today over the Sierra and southern Cascades
    and adjacent foothills

  - Mainly dry this weekend, with some mountain showers Sunday
    over Shasta County.

  - Gradual warming trend this weekend and into early next week,
    but highs likely remain below average for this time of the
    year

  - There is the potential for monsoonal moisture mid-next week,
    but confidence in details remains low at this point

&&

.DISCUSSION...Lingering shower activity continues to taper off to
the east this afternoon as dry air mass filter over the area.
However, some additional mountain showers are expected in Shasta
County late this afternoon and evening as the next shortwave
trough embedded within a broad upper- level trough centered over
NW Oregon/SW Washington swing northeastward today. Elsewhere,
generally mostly cloudy skies, with a gradual clearing skies into
the weekend. Winds will continue to ease and become weaker across
the area into Saturday.

The broad upper-level trough begin to weakens over the weekend. Mostly
dry weather with below normal temperatures is forecast across the
interior NorCal on Saturday, but a few showers are possible over
the Sierra crest during the afternoon. Daytime temperatures are
forecast to be up to around 5 degrees warmer on Saturday, with
highs into the 80s across the valleys. The through is expected to
drift back to northern California, with an embedded shortwave
trough bringing a slight chance of mainly Shasta County showers,
generally dry elsewhere. In addition, an enhanced in the onshore
winds is expected. West gusts up to 25 mph in the Delta possible,
with up to 35 mph over the Sierra.

Dry weather with a warming temperatures trend is expected early
next week as the persistent trough shift eastward, a brief
shortwave ridge builds in. Meanwhile, ensemble and deterministic
models continues to suggest an upper-level trough developing
quickly off California. There is a consensus between models with
this trough absorbing the current Hurricane Marie mid-next week.

There is still some potential for monsoonal moisture moving into
California mid next week, but confidence in precipitation
potential from this extending into interior Northern California
remains fairly low. Currently the best potential for rain is over
the mountains south of I-80 on Thursday, especially in the
mountains. Temperatures trend warmer, with near to above normal by
mid to late next week..

&&

.AVIATION...Periods of MVFR with ceiling restrictions are
impacting the terminals south of the I-80, while VFR conditions
remain at KRDD and KRBL. Expect VFR conditions at all terminals
this afternoon, with VCSH at KRDD and KRBL from 05/02Z-05/05Z.
There is a 20-30% chance for MVFR ceilings from 11Z-16Z for KSMF,
KSAC, KMCC and KMHR. Any low clouds will cleared after 16Z
Saturday. Valley winds south to west around 5-10 kts today and
Saturday. Winds over the Sierra will continue to ease throughout
the day.


&&

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

$$