Mountain House, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

230
FXUS66 KSTO 221952
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1152 AM PST Sun Feb 22 2026

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

.KEY MESSAGES...

 - Warm storm brings additional rounds of rain, gusty southerly
   winds and high elevation mountain snow Sunday through mid next
   week. Latest forecast trends continue to decrease snow and have
   reduced rain totals for the region.

 - Dry and warming conditions likely by Thursday continuing
   through the weekend

&&

.DISCUSSION...

...Today...
Mostly light scattered rain showers observed in portions of the
northern Sacramento Valley this afternoon. Light precipitation
expected to continue through the day mostly confined to the
Coastal Range and Tehama, Shasta Counties. Elsewhere mostly sunny
with a few passing high clouds expected to continue today, with
warmer high temperatures.

...Monday - Wednesday...
Our next system continues to trend further offshore from NorCal,
and with the trend westward precipitation totals have decreased
with the afternoon forecast update. Light, scattered rain showers
are forecast to move into the area Monday evening then becoming
more widespread by Tuesday morning. Heaviest precipitation is
still likely to remain in the northern Sacramento Valley,
foothills, and mountains on Tuesday through early Wednesday. Snow
levels begin around 6000 feet Monday, so some light accumulations
at the higher elevations are possible, then by Tuesday morning
snow levels climb to 8000-9000+ feet and continue to remain at
those levels through Wednesday. Periods of breezy to gusty
southerly winds on Tuesday, with strongest winds in the northern
Sacramento Valley and NE foothills around 20-30 mph. Wind forecast
has trended down somewhat this afternoon as well, with the further
westward movement of the low pressure reducing the PGF in our
area.

For precipitation totals, snow accumulations likely confined to
highest elevations with 1-3 inches, Lassen NF up to a foot or so
of snow through Wednesday. Rain totals for the Valley have
decreased. Roughly around 1-3 inches from Tehama County and Shasta
County, similar totals in the foothills and Sierra, southern
Cascades and the Coastal Range. For the rest of the Valley and
Delta, around 0.10 to 1.00" inches in the forecast now. With the
south to northeast orientation of the IVT plume and the further
retrograding of the synoptic support, central and southern Sac
Valley and northern San Joaquin Valleys, and the Delta will likely
experience more of a shadowing effect, so rain totals within the
NBM have responded as result. Some of the lower foothills may see
a flooding risk from snow melt with warmer air and rainfall;
however we do not anticipate a large scale risk of flooding from
the incoming rain at this time.

...Thursday - Saturday...
Upper level ridging is forecast to develop off the coast of Baja
California, which will result in drying conditions across
interior NorCal and warming high temperatures. Valley locations
will likely see 70 degree high temperatures by Thursday continuing
into next weekend.

&&

.AVIATION...

Generally VFR conditions across Valley TAF sites next 24 hours.
Surface winds below 12 knots in the Valley; gusts up to 20 kts in
the mountains. Brief period of BR conditions in northern San
Joaquin Valley from around 09z through 17z Monday. 10-20% chance
of -SHRA/-RA at RDD and RBL through 12z Monday.
&&

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

$$