740
FXUS66 KSTO 192010
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
Issued by National Weather Service Reno NV
110 PM PDT Mon May 19 2025

.Discussion...

.Synopsis...
Red Flag Warning continues for Valley and Delta locations below
1000 feet through 8 PM PDT Monday. Warming trend and areas of
Moderate HeatRisk in the Valley expected through the middle of the
week as ridging aloft briefly settles in. A gradual cool down to
near to slightly above normal is then anticipated late week into
next weekend as a more progressive pattern sets up aloft.
Precipitation chances less than 5 percent, but periods of breezy
to briefly gusty winds possible. Elevated fire weather conditions
expected to persist.

&&

.Key Messages...

* Red Flag Warning in effect through 8 pm PDT this evening for
  Valley and Delta locations below 1000 feet.

* Today - Wednesday:
 -Breezy/Gusty north winds across the area today, with low
  humidity values across the Valley and Delta. Critical fire
  weather conditions continue through this evening.
 -Above normal high temperatures warm in the 80s to low 90s today
  and Tuesday, with Valley highs into the mid 90s and areas of
  Moderate HeatRisk on Wednesday.
 -Very dry conditions and diurnally breezy winds expected as
  elevated fire weather conditions persist.

* Thursday - Saturday:
 -Quick moving, dry shortwaves bring periods of breezy to briefly
  gusty onshore winds Thursday and Friday.
 -Elevated fire weather conditions likely continue, especially
  during periods of strongest winds as systems move through.
 -Gradual cooling to near to slightly above normal temperatures,
  with primarily Minor HeatRisk anticipated.

.Changes from previous forecast...
 -Periods of breezy to briefly gusty onshore winds Thursday and
  Friday as progressive, dry weather systems traverse the region.

&&

.AVIATION...
VFR conditions prevail across interior northern California over
the next 24 hours. Northerly wind gusts of up to 15 to 25 knots at
times across the Central Valley and Delta through 03Z Wednesday,
strongest through 02Z Tuesday.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 8 PM PDT this evening for Carquinez
Strait and Delta-Central Sacramento Valley in Glenn, Colusa,
Yuba, Northern Sutter, and Butte County Below 1000 Ft-Northern
Sacramento Valley to Southern Tehama County Line Below 1000 Ft-
Northern San Joaquin Valley in San Joaquin and Stanislaus
Counties Below 1000 ft-Southern Sacramento Valley in Yolo-
Sacramento Far Western Placer, southern Sutter and Solano County
Below 1000 Ft.

&&

$$