659
FXUS66 KSTO 111936
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1236 PM PDT Mon May 11 2026

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

.KEY MESSAGES...

 - Hot and dry conditions throughout the week.

 - Hottest Day Today with lingering heat into Tuesday with
   possible daily record highs and widespread Moderate HeatRisk.

 - Slightly cooler temperatures from Wednesday onward, though
   temperatures will still be well above normal.

&&

.DISCUSSION...

...Today through Tuesday...

A Heat Advisory is in effect today until Tuesday 8 PM for
portions of the Valley, including portions of the Butte, Colusa,
Stanislaus, and Glen counties for near triple digit highs and
Moderate HeatRisk. The brunt of the heat will be today with
forecasts trending cooler but still above normal temperatures on
Tuesday. After Tuesday late afternoon and evening, a trough moving
through the PacNW will help push the ridging eastward and reduce
heat impacts over the area. Current probabilities for 100 degrees
have lowered to around 10-25%. generally limited to Stanislaus
County and to around where Glenn, Colusa, and Butte Counties meet.

Be sure to practice heat safety! Drink plenty of fluids, stay in
an air-conditioned room or in the shade during the heat of the
day, and consider checking in on those more susceptible to heat.

...Wednesday through Saturday...

As previously mentioned, ensembles depict the ridge breaking down
towards the middle of the week, which will result a decent amount
of cooling on Wednesday. As lower pressure moves through the area
on Wednesday, the change in pattern brings with it light showers
and a slight chance (5-15%) for isolated thunderstorms in the
northern Sacramento Valley, as well as the foothills and mountains
north of HWY 50. Best chances are in northeastern Shasta County,
though any thunderstorm chances are somewhat uncertain in the
ensembles and will depend on the path of the troughing. Overall,
impacts should be limited with most places staying dry than not.
Lastly, dry conditions persists particularly over the Valley,
north of Interstate 80 getting into the teens and upper single
digits.

Please continue to practice fire safety and monitor your latest
forecast to stay up to date at weather.gov/sacramento

&&

.AVIATION...

General VFR conditions are expected over the next 24 hours.
Surface winds generally 12 kts or less through Tuesday morning,
except near the Delta, where winds to 15 kts and gusts to 20 kts
are possible. Breezy south-southwest winds develop after 18z
Tuesday, with gusts up to 15-25 kts in the Valley and Delta, and
up to 25-35 kts over the mountains.


&&

.STO WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM PDT Tuesday for Butte County Below 1000
ft-C. Stanislaus County including Modesto-Eastern Colusa County-
Eastern Glenn County-W. Stanislaus County Above 1000 ft & I-5.

&&

$$