581
FXUS66 KSTO 291922
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1222 PM PDT Wed Jul 29 2026

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


.KEY MESSAGES...

 - Elevated Fire Weather Conditions in the northern Sacramento
   Valley, Burney Basin, and Sierra Foothills Friday through
   Sunday due to Hot Temperatures and Low Humidities.

 - Widespread Moderate HeatRisk Friday into early next week across
   the Valley and Foothills.

&&

.DISCUSSION...

Clear and sunny skies are being observed alongside seasonable
temperatures across interior Northern California this afternoon.
Warm temperatures continue today with breezy afternoon/evening
winds due to upper level troughing over Northern California.
Tomorrow, heights begin to increase aloft alongside temperatures
as high pressure ridging builds overhead. As ridging amplifies
further on Friday, Moderate HeatRisk becomes widespread across the
Valley and foothills, with patchy coverage in the mountains
through early next week. This upper ridge continues to strengthen
over the western US Saturday-Monday which is when the hottest
temperatures of the period are expected. Probabilities and
forecast confidence remain high for the Valley to see triple digit
temperatures this weekend and into early next week as EFI signals
for anomalous high temperatures expand in areal coverage through
the Valley.

During this period of elevated temperatures, minimum relative
humidities will approach the low teens accompanied by poor
overnight recoveries across the Sierra foothills (where thermal
belts develop), the Burney Basin, and the northern Sacramento
Valley. This will result in Elevated Fire Weather conditions
across the aforementioned locations Friday-Sunday. A weak
shortwave will clip the northern most portion of California
Saturday-Sunday, resulting in enhanced gap flow through the Coast
Range and western Shasta/Tehama counties on Saturday followed by
increased northerly flow along the I-5 corridor in the Sacramento
Valley on Sunday. This will further lower daytime RHs and possible
leading to additional elevated fire weather concerns.

Guidance shows the potential weakening of the upper ridge mid
next week which will lead to temperatures being a few degrees
cooler (but still hot) compared to the weekend. Longer range
guidance struggles to confidently depict whether the ridge will
continue to weaken or restrengthen late next week. None the less,
confidence is very high in regards to the heat and dry conditions
this weekend so make sure to stay hydrated and limit outdoor
activities.

&&



.AVIATION...
VFR conditions prevail through the TAF period. Winds will be out
of the southeast to southwest for the Sacramento sites at 5-10kts
this afternoon/evening, with north to northwest winds at MOD and
SCK. RDD and SCK may see brief winds up to 12 kts. A few gusts up
to 20kts can`t be ruled out this afternoon and evening, especially
through the Delta and northern Sacramento Valley. Winds go light
and variable for the TAF locations after 6Z, with continued clear
skies.

&&

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

$$