Mount Aukum, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

260
FXUS66 KSTO 162147
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
147 PM PST Mon Feb 16 2026

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


.KEY MESSAGES...

 - Widespread rain, gusty winds, isolated thunderstorms,and
   substantial mountain and foothills snow expected throughout the
   week.

 - Major travel impacts in the mountains and foothills with light
   snowfall accumulations possible below 1000 feet in Shasta
   County on Wednesday and Thursday mornings.

 - Potential for active weather to continue into next weekend.

&&

.DISCUSSION...

...Today through Friday...
A strong and cold trough brings widespread moderate to heavy
rain, periods of heavy snow for the mountains and foothills, gusty
south winds, and isolated thunderstorm chances to interior NorCal
throughout the week. Snow levels around 3500-4500 feet today are
expected to fall to around 1500-2500 feet from Tuesday onward.
Some fluctuations down to 1000 feet along the Sierra and below
1000 feet in the northern Sacramento Valley will be possible,
particularly on Wednesday and Thursday morning. Heaviest snowfall,
with snowfall rates up to 2 inches per hour, is expected through
Tuesday, followed by a brief break of light to moderate snowfall
on Wednesday, with snowfall rates up to 1 inch per hour returning
by Thursday. As a result, the Winter Storm Warning has been
extended through 10 pm Thursday evening and to include low
elevation portions of Shasta County.

Likewise, as periods of gusty south to west winds continue as the
system remains over the region this week, the Wind Advisory has
been extended through 10 pm Thursday, with strongest winds gusting
35 to 45 mph, anticipated Tuesday and late Wednesday through
Thursday. While periods of moderate to heavy rainfall are expected
for most Valley locations, instances of urban and roadway
flooding will likely continue, with some potential for rises on
small streams and creeks. Additionally, isolated thunderstorms
will be possible in the afternoon and evening hours tonight and
Tuesday, although the highest chances, up to 20%, are currently
anticipated on Tuesday throughout most of the Valley. Primary
hazards with any thunderstorms that develop will be heavy
precipitation, small accumulating hail, and gusty winds, with a
low chance for an isolated funnel cloud or weak tornado.

Ensemble guidance is generally in agreement that by late in the
week, the trough will begin ejecting eastward toward the Rockies.
This looks to introduce a period of primarily dry weather to the
region on Friday, although some lingering mountain snow showers
will remain possible. While some uncertainty remains with respect
to the intensity of lingering snowfall on Friday, at least gradual
improvements in travel conditions are anticipated at this time.

...Next Weekend...
While the aforementioned system currently impacting the region is
expected to trail off as it pushes eastward, ensemble guidance is
beginning to indicate a separate trough digging southward from
the Gulf of Alaska by the weekend. Exact timing and resultant
details remain highly uncertain, but there is increasing potential
at this time for additional periods of active weather to continue
through the weekend and into early next week.

&&

.AVIATION...

MVFR/IFR conditions expected in areas of -RA/RA and possible TSRA
at TAF sites through 03z Tuesday followed by a brief break in
precipitation and a return to generally VFR conditions overnight.
Highest chances for TSRA expected between 22z and 03z Tuesday.
Additional MVFR/IFR in precipitation then expected to spread
through the region after 10z Tuesday. Breezy winds with variable
direction up to 11 kts through 00z become predominantly south
winds after 03z with an expected increase in wind/wind gusts
moving toward 12z Tuesday.

IFR/LIFR conditions in SN/+SN expected across the mountains today
followed by a brief break overnight after 06z Tuesday with
similar conditions returning by 12z Tuesday. Snow levels around
3500-4500 feet begin falling to 2500-3500 feet after 06z Tuesday.
West- southwest winds remain gusty through the forecast period
with surface wind gusts up to 40 kts at times.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 10 PM PST Thursday for Burney Basin /
Eastern Shasta County-Motherlode-Mountains Southwestern Shasta
County to Western Colusa County-Northeast Foothills/Sacramento
Valley-Northern Sacramento Valley-Shasta Lake Area / Northern
Shasta County-West Slope Northern Sierra Nevada-Western Plumas
County/Lassen Park.

Wind Advisory until 10 PM PST Thursday for Central Sacramento
Valley-Northern Sacramento Valley-Southern Sacramento Valley.

&&

$$