Day 3-8 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
0500 PM CDT Tue Aug 25 2026

Valid 271200Z - 021200Z

...Synopsis...
An upper ridge will gradually translate eastward into the northern
Plains as a mid-level shortwave trough progresses through the
Pacific Northwest on Day 3/Thursday. Meanwhile, large-scale ascent
will overspread the Northern Rockies into central Montana, promoting
thunderstorm potential where dry fuels exist. A cold front will
sweep across the Columbia Basin, bringing strong winds and modestly
low RH values to a drought-stressed environment with numerous
ongoing wildfires on Day 3/Thursday. Strong southwest-westerly flow
will continue across the northwestern CONUS into the weekend, with
embedded disturbances within persistent upper troughing and along
the northern periphery of the flattening ridge. Long term guidance
suggests a secondary shortwave trough could enter the Northwest and
contribute to the breakdown of the upper ridge atop the Four Corners
this weekend. As a result of the upper pattern, fire weather
concerns will likely continue through the forecast period across the
parts of the Northwest, Great Basin and Northern Rockies. However,
low predictability and poor agreement among ensemble clusters
precludes additional probabilities beyond Day 5/Saturday.

...Dry Thunderstorms...
The arrival of the next upper-level wave will bring additional
opportunities for afternoon thunderstorms across portions of the
Northern Rockies and Montana plains on Day 3/Thursday. A dry
boundary layer and fast storm motions will favor evaporation and
less precipitation efficiency, raising concerns for
lightning-induced ignitions within an increasingly receptive
fuelscape. 10% Dry Thunderstorm probabilities were introduced on Day
3/Thursday, though may need to be confined in future outlooks where
multiple days of an overlapping thunderstorm threat could increase
recoveries.

...Northwest, Northern Great Basin and Northern Rockies...
A drier southwest flow pattern will bring a multi-day fire weather
threat to portions of the northwestern U.S., with fire weather
concerns extending eastward into the Montana plains later this week.
40% Critical probabilities have been maintained with minor
adjustments for Days 3-5/Thursday-Saturday, and introduced across
north/central Montana on Day 4/Friday. West to southwest winds of
15-20 mph and afternoon relative humidity between 15-20 percent will
bring daily elevated fire weather concerns, potentially impacting
nascent wildfires born from thunderstorm activity early in the
forecast period. Critical fire weather conditions with winds of 20+
mph are likely but only in localized areas, particularly from
northeastern CA into far northwestern NV and southeastern OR on Day
3/Thursday. 

...Southern California...
Above average daytime temperatures and poor humidity recoveries are
forecast across portions of southern California through the
week/early weekend. Offshore flow will present overnight/early
morning periods of gusty winds and critically low RH values in Santa
Barbara/Ventura/LA counties amid very dry fuels, raising concerns
for locally elevated fire weather conditions. As such, 40% Critical
probabilities were introduced on Days 3-4/Thursday-Friday.

..Elizalde-Garcia.. 08/25/2026

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