044
FXUS66 KSTO 091908
AFDSTO
Area Forecast Discussion
National Weather Service Sacramento CA
1208 PM PDT Tue Jun 9 2026
For additional details on weather and expected impacts over the
next 7 days, please visit weather.gov/sto/briefing.
.KEY MESSAGES...
-Near normal temperatures with breezy onshore winds today.
-Critical fire weather conditions in the Sacramento Valley
Wednesday - Thursday due to gusty north winds and low humidity.
-Significant warm up starting mid-week brings triple digits in
the lower elevations with widespread Moderate HeatRisk and areas
of Major HeatRisk into the weekend.
&&
.DISCUSSION...
Mostly clear skies this afternoon as the upper level trough begins
to fully exit the region. Near normal max temperatures continue
today, with the Valley seeing highs in the mid to high 80s this
afternoon.
As the early-week trough shifts into the Great Basin, we`ll see
winds become stronger and more northerly on Wednesday and into
Thursday. As north winds increase, conditions will dry out with
daytime relative humidity dropping into the single digits to teens
across the Sacramento Valley with limited overnight recovery.
Ensemble guidance and EFI are in good agreement with highest
threat across the typical western side of the Sac Valley. Our Red
Flag Warning remains in place from 11am Wednesday to 5pm Thursday,
and now includes the western foothills along the central and
southern Sacramento Valley (in addition to the majority of the
Sacramento Valley).
As critical fire weather conditions continue on Thursday,
temperatures will also see significant increases as upper level
ridging builds along the West Coast. Triple digit Valley highs are
forecasted starting Thursday and continuing through at least the
early weekend in many locations. Widespread Moderate HeatRisk is
expected starting Thursday, with areas of Major HeatRisk on
Friday and Saturday. To this point, we have issued a Heat Advisory
for the northern and central Sacramento Valley and adjacent
foothills from 11am Thursday, June 11, to 11pm Saturday, June 13.
While other areas in the Valley will benefit from the Delta`s
cooling influence, especially in the evening, it remains important
for everyone in interior NorCal to practice heat safety! Stay cool
and hydrated, and consider checking in on those more sensitive to
heat.
There remains some uncertainty in regards to the rate of cooling
into next week, but regardless temperatures should begin to cool
again slightly starting Sunday as ridging gradually flattens.
&&
.AVIATION...
VFR conditions next 24 hours. North gusts 15 to 20 kts in the
northern San Joaquin until 07Z Wednesday and west wind gusts 15 to
20 kts in the vicinity Delta until 05Z Wednesday. Elsewhere
surface winds 12 kts or less.
North winds increase through the northern/central Sacramento
Valley after 15Z Wednesday with sustained winds 15 to 20 kts and
gusts 25 to 40 kts. East gusts over the mountains up to 40 kts.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 11 AM Thursday to 11 PM PDT Saturday for
Butte County Below 1000 ft-Central Colusa County Incl. I-5-
Central Glenn Co & Interstate 5-Eastern Colusa County-Eastern
Glenn County-N. Sac Valley in Tehama County-Shasta Metro-Sierra
(Tehama-Plumas) 1000-3000 ft-Sutter/Yuba counties below 1000 ft-
W Tehama Co Foothills 1000-3000 ft-W. Glenn/Colusa Foothills
1000-3000 ft-W. Shasta County 1000-3000 ft.
Red Flag Warning from 11 AM Wednesday to 5 PM PDT Thursday for
Butte County Below 1000 ft-C. Yolo/NE Solano including Woodland-
Central Colusa County Incl. I-5-Central Glenn Co & Interstate 5-
Eastern Colusa County-Eastern Glenn County-N. Sac Valley in
Tehama County-Shasta Metro-Sutter/Yuba counties below 1000 ft-W.
Glenn/Colusa Foothills 1000-3000 ft-W. Yolo County including
Capay/I-505-Yolo / Solano County Hills.
&&
$$