Sites, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

283
FXUS66 KSTO 031902
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1202 PM PDT Sun May 3 2026

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


.KEY MESSAGES...

 - Showers and thunderstorms this afternoon and evening for the
   mountains, foothills, and northern Sacramento Valley. A few
   isolated strong to severe storms are possible.

 - Continued chances for showers and thunderstorms Monday
   afternoon/evening and again on Tuesday for the mountains,
   Valley, and foothills.

 - Hot and dry conditions are expected to develop end of the week
   and into next weekend, with Minor and Moderate HeatRisk.


&&

.DISCUSSION...

...Sunday through Tuesday...

Upper level system is tracking across the Southwestern United
States bringing moisture, instability, and sufficient shear to the
region. Breaks in the cloud coverage at times has helped increase
instability across the area. Current satellite and radar have a
few cells developing in the mountains around Hwy 50 and tracking
NW. HIRES guidance has picked up on this and started to initialize
further development around 20-21z and continuing through the
evening hours. Shear profiles show sufficient speed and
directional shear to support thunderstorm growth. A few of the
thunderstorms could be strong to severe, with hail up to 1 inch,
gusty winds, frequent lightning, and brief heavy rain rates. Make
sure you have a way to receive alerts this afternoon and evening.

Precipitation chances shift down into the Valley overnight and
into tomorrow morning with scattered rain showers Monday morning.
Chances for thunderstorms arise once again during the afternoon
and evening, with a few stronger storms possible. We will continue
to see rain and thunderstorm potential into Tuesday, but chances
are on the lower end as the main upper level system shifts further
away from the area.

At the highest peaks south of Highway 50 there will be chances
for snow tonight through Tuesday, with minor accumulations
possible.

Temperatures through Tuesday will be on the cooler side across the
area, with highs in the 60s to lower 70s Monday and the 70s on
Tuesday.

...Wednesday and beyond...

Conditions dry out as we move into Wednesday and continue into
next weekend. An upper level ridge builds and amplifies over the
western United States end of the week into next weekend. This
increases our temperatures and drys out conditions across the
area. Minor HeatRisk is expected across the Valley Wednesday, but
becomes more widespread into the foothills and mountains by the
end of the week. Minimum RH values start to drop into the 20s
across the area, with a few isolated values in the teens. By next
weekend, we are seeing increasing confidence temperatures will
reach into the 90s, with the probabilities of seeing over 95
degrees 50-60 percent Saturday and Sunday. Potential for Moderate
HeatRisk Saturday.

&&

.AVIATION...

BKN to OVC skies through the TAF period, with thunderstorm chances
near RDD and RBL this afternoon and evening. Winds will begin to
increase out of the southwest at 10-15kts for the Sacramento
sites this afternoon and go light and variable overnight. Near
08z-13z chances for rain develop through the Valley affecting each
site through the end of the TAF period. Ceilings go MVFR during
this time.

&&

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

$$