205
FXUS66 KSTO 011909
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1209 PM PDT Sat Aug 1 2026

.KEY MESSAGES...

 - Elevated Fire Weather Conditions in the northern Sacramento
   Valley and surrounding terrain, Burney Basin, and Sierra
   Foothills through Monday due to hot temperatures, low
   humidities, and breezy winds.

 - Widespread Moderate HeatRisk persists into next week across the
   Valley and Foothills. Hottest temperatures expected through
   Tuesday.

&&

.DISCUSSION...

Today-Tuesday...

As of midday today, interior NorCal remains underneath split flow
aloft as ridging aloft builds in over the region with pronounced
troughing beginning to move onshore toward the Pac NW. Resultant
high temperatures today trend above normal with widespread triple
digit high temperatures and more limited overnight cooling
anticipated through Tuesday afternoon. Current probabilities for
high temperatures greater than 100F sit around 60-90% for the
Delta, Valley, and lower foothills. Additionally, 50-80%
probabilities of high temperatures greater than 105F are forecast
for the northern Sacramento Valley. As a result, moderate HeatRisk
is expected prevail area wide.

As the aforementioned trough tracks eastward through the weekend,
periods of breezy north to west winds are expected to develop at
times across the northern Sacramento Valley and surrounding
terrain. The periods of stronger winds are anticipated late this
afternoon into midday Sunday and again Sunday evening into midday
Monday, with strongest winds gusting 20-30 mph currently forecast
for Monday morning. The combination of low daytime humidity values
into the lower teens and upper single digits, limited overnight
humidity recovery, and periodically breezy to gusty winds will
introduce elevated fire weather conditions to the northern
Sacramento Valley and surrounding terrain, Burney Basin, and
Sierra foothills through Monday.

Wednesday through next week...

As the passing longwave trough flattens the ridge, broader
reinforcing onshore flow remains on track for interior NorCal mid
to late week. A very slight cool down is anticipated as this
weather pattern develops, although widespread Moderate HeatRisk is
still expected to persist. While high temperatures into the upper
90s to triple digits are likely to continue across much of the
region, increasing onshore flow and the return of a more
persistent Delta Breeze pattern is expected to provide some
overnight relief for Delta and vicinity Valley locations. Despite
improving humidity recovery for Delta Breeze influenced locations,
low daytime humidity and poor overnight recovery is likely to
continue in the northern Sacramento Valley as well as portions of
the mountains and foothills.

&&

.AVIATION...

VFR conditions are expected to prevail over the next 24 hours.
Winds generally remain 12 kts or less at TAF sites from Interstate
80 southward, although southwest gusts up to 18 kts in the Delta
through 06z Sunday. Increasing west to north winds are anticipated
at RDD and RBL after 00z Sunday, with potential for gusts up to
20 kts at times through Sunday morning.


&&

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

$$