668
FXUS66 KSTO 101937
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1237 PM PDT Sun May 10 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 Days Monday and Tuesday with triple digit temperatures,
   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...

Hot temperatures continue today and through early this week as ridging
builds eastward. Widespread Minor HeatRisk with areas of Moderate
Heat Risk is expected today in the Valley. Maximum Valley temperatures
today will be primarily be in the low 90s, though closer to the
Delta temperatures will remain a little cooler thanks to the
influence of the Delta Breeze.

On Monday and Tuesday, daytime temperatures will climb again,
with widespread Moderate HeatRisk in the Valley both days. Valley
highs have potential to both meet or exceed local records, as well
as reach triple digits in some locations. The NBM has a 30 to 50%
chance of 100 degrees or more in the northern San Joaquin Valley,
as well as in the central Sacramento Valley (particularly around
eastern Glenn and Colusa Counties, and Butte County). A Heat
Advisory remains in place for these areas from 11am on Monday
through 8pm on Tuesday. Areas closer to the Delta will see much
better overnight relief on Monday and Tuesday, though daytime
temperatures will still be quite hot. 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...

Ensembles depict the ridge breaking down towards the middle of
the week, which will result a decent amount of cooling on
Wednesday; however temperatures will still be 5 to 15 degrees
above normal through the end of the week. As lower pressure moves
through the area on Wednesday, the change in pattern brings with
it a slight chance (10-20%) 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.

&&

.AVIATION...
General VFR conditions are expected over the next 24 hours.
Surface winds generally 12 kts or less except near the Delta,
where winds to 15 kts and gusts to 20-25 kts are possible through
12z on Monday.


&&

.STO WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 11 AM Monday to 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.

&&

$$