609
FXUS66 KSTO 282105
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
205 PM PDT Sat Jun 28 2025

.DISCUSSION...

.SYNOPSIS...
Warm and dry weather continues into next week with periodically
breezy onshore winds. Widespread Moderate HeatRisk is anticipated
this weekend, with areas of Moderate HeatRisk persisting into the
middle of next week. Mountain thunderstorm chances return next
week. Lightning on dry fuels may lead to easier fire starts early
next week.

&&

.KEY MESSAGES...

* This Weekend:
 -Warming trend with high temperatures across the Delta, Valley,
  and foothills in the 90s to lower triple digits and 80s to low
  90s expected at higher elevations
 -Widespread Moderate HeatRisk across interior NorCal
 -Probability of Valley high temperatures > 100F:
  Northern/Portions of the Central Sacramento Valley: 65-95%;
  Delta, S. Sac Valley, N. San Joaquin Valley: 10-30%

* Early to Mid Next Week:
 -Above normal temperatures persist into next week with Moderate
  HeatRisk, although increased onshore flow brings some relief to
  the Delta vicinity Monday-Tuesday
 -Slight (10-20%) probability of thunderstorms early to mid next
  week during the afternoon and early evening hours across the
  mountains of interior NorCal. Highest thunderstorm probabilities
  over the northern mountains on Monday-Tuesday. Thunderstorm
  chances expand farther south into the Sierra by Wednesday.
 -Lightning on dry fuels may lead to easier fire starts. A Fire
  Weather Watch has been issued for the northern Coast Range,
  Shasta County mountains and Burney Basin from 11 AM - 11 PM
  Monday.

* Late Next Week:
 -Slight cooling trend with Minor HeatRisk returning to interior
  NorCal
 -Potential for mountain thunderstorm chances (10-20%) persisting
  through late week.

.Changes from previous forecast...
 -Fire Weather Watch for lightning on dry fuels for the northern
  Coast Range, Shasta County mountains and Burney Basin from 11
  AM to 11 PM Monday.
 -Less widespread Moderate HeatRisk on Wednesday.

&&

.AVIATION...
VFR conditions prevail across interior NorCal next 24 hours.
Surface wind gusts below 15 kts, except in the Delta vicinity
where surface gusts up to 20 kts are possible through 06Z Sunday
and again after 00Z Monday.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Monday morning through Monday evening
for Burney Basin and Northeast Plateau in Shasta County
Including Northwest Lassen NF north of Lassen NP-Eastern
Mendocino NF-Eastern Portion of Shasta/Trinity NF-Southeast Edge
Shasta-Trinity NF and Western Portions of Tehama-Glenn Unit.

&&

$$