797
FNUS28 KWNS 192027
FWDD38

Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0325 PM CDT Tue Aug 19 2025

Valid 211200Z - 271200Z

The breakdown of the upper-level ridge over the northern Rockies
will be complete on Day 3/Thursday. Monsoonal moisture will continue
to push west and north into California, the Great Basin, and the
Rockies of Colorado and Wyoming into the weekend as the upper-level
ridge rebuilds over the West. Thunderstorm coverage will increase
across these areas with wetter storms anticipated. Hot, dry, and
unstable conditions will precede and follow along the leading edge
of the monsoonal moisture as it traverses west/north.

A 10% area for dry thunderstorms was introduced on Day 3/Thursday in
the higher terrain of Utah, western Wyoming, and eastern Nevada.
PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud
layer, although storm motions will be slower over Utah and parts of
Nevada under the upper high. Areas of dry thunderstorms are likely
near the leading edge of the monsoonal moisture in portions of
California and the Great Basin possibly into the weekend. However,
enough uncertainty regarding the magnitude, timing, and location of
the monsoonal moisture exists to preclude additional probabilities
later in the outlook period. Some areas in the southern/central
Intermountain West are likely to have only one day of dry or mixed
wet/dry thunderstorms before deeper moisture moves in and mitigates
fire weather concerns.

Hot, dry, and unstable conditions will increase across the West
ahead of the monsoonal moisture from California and the Great Basin
eventually into the Northwest and northern Rockies by the weekend. A
strong West Coast thermal trough is likely to develop and will be
monitored for potential offshore winds and focus for hot, dry,
unstable, and breezy conditions. The duration of these hotter and
drier conditions remains uncertain as forecast guidance of the
upper-level pattern early next week over the West is a mix of
persisting ridging and some sort of weakening or break down of the
ridge.

..Nauslar.. 08/19/2025

...Please see www.spc.noaa.gov/fire for graphic product...

$$