Grass Valley, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

520
FXUS66 KSTO 071743
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1043 AM PDT Thu May 7 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 are expected to develop early next week
   with Moderate HeatRisk Sunday-Tuesday.

 - Hottest Days Monday and Tuesday with triple digit and daily
   record highs possible.

 - Temperatures will still be above-normal Wednesday onward, but
   follow a gradual cooling trend with increased delta breeze
   influence.

&&

.DISCUSSION...

...Thursday through Wednesday...
Temperatures continue on a warming trend today with high
temperatures 5 to 10 above normal as ridging builds over the
eastern Pacific before moving over Northern California this
weekend. Warmer and drier conditions will continue through the
weekend, with widespread Minor HeatRisk through Saturday, with
areas of Moderate in the foothills. Moderate HeatRisk becomes more
widespread Monday through Tuesday. Lingering troughing influence
will lead to an increased Delta breeze today through Sunday, as a
result there may be some marine stratus intrusion in the morning
especially on Friday and Saturday.

Hottest days are expected to be Monday and Tuesday, with highs in
the upper 90s to around 100. There is some uncertainty on whether
locations will climb into the triple digits as the latest
ensembles show the ridge axis further eastward over Nevada, but
temperatures are still on track to be 10 to 20 degrees above
normal. As a result, some places may see tied or broken daily high
temperature records. The NBM indicates a 70 to 95% chance of 90
or greater throughout the entire Valley and Delta next Monday and
Tuesday, with a 30 to 50% chance of 100 or more across portions of
the central Sacramento Valley and northern San Joaquin. There may
be some Delta breeze to give influenced areas a slight break for
overnight lows. Minimum RH values trend lower through early next
week as well, dropping into the 20s and teens by Monday.

Ensembles depict the ridge breaking down towards the middle of
next week which will result in a gradual cooling trend Wednesday
onward, however temperatures will still be 5 to 15 degrees above
normal. Delta breeze influence is expected to pick back up mid
week as well.

 &&


.AVIATION...
General VFR conditions are expected over the next 24 hours. Local
MVFR/IFR ceilings are possible with marine stratus through the
Delta and impacting Sacramento area TAF sites 12-18Z Friday.
Surface winds generally 12 kts or less except near the Delta,
where winds to 15 kts and gusts to 20-25 kts.

&&

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

$$