336
FNUS21 KWNS 251653
FWDDY1

Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1152 AM CDT Sat Jul 25 2026

Valid 251700Z - 261200Z

...CRITICAL FIRE WEATHER AREA FOR SCATTERED DRY THUNDERSTORMS ACROSS
CENTRAL/SOUTHERN MONTANA...
...CRITICAL FIRE WEATHER AREA FOR MUCH OF THE PACIFIC NORTHWEST INTO
THE NORTHERN ROCKIES...

Meteorological conditions amid numerous wildfires and 90-95th
percentile ERCs across the northwestern U.S. will lead to another
day of expansive, and potentially dangerous, fire concerns.

A Scattered Dry Thunderstorm risk was introduced across
central/southern Montana where a greater coverage of thunderstorms
and lightning ignitions are possible atop receptive fuels. Forecast
soundings depict a hot and well-mixed environment this afternoon
with deep inverted-V profiles, ample MUCAPE, and 25-35 kt LCL-EL
winds, indicating thunderstorms will be capable of severe
wind-potential and less precipitation efficiency (See the Day 1
Convective outlook). The Isolated Dry Thunderstorm risk area was
expanded into northwestern South Dakota and northeastern Wyoming
based on the latest observations and forecast guidance. Lightning
ignitions are also possible outside of the Isolated Dry Thunderstorm
highlights, on the periphery of heavier precipitation cores where
fuels are receptive.

Despite moderate RH recoveries across portions of the Pacific
Northwest, values are quickly declining and will approach critical
thresholds (15% or less) by peak heating. Southwesterly to westerly
sustained surface winds are expected to exceed 20 mph, perhaps
approaching 25 mph in terrain-favored areas. Locally extremely
critical conditions may be possible where these stronger sustained
winds overlap critically low RH, in addition to wind gusts of 30-40
mph particularly in the Columbia Basin and western/central Montana.
These conditions will further exacerbate the fire environment,
impacting any new/ongoing wildfires and control efforts.

..Elizalde-Garcia.. 07/25/2026

.PREV DISCUSSION... /ISSUED 1143 PM CDT Fri Jul 24 2026/

...Synopsis...
Upper ridging will prevail over the western and central CONUS today.
A belt of stronger mid-level flow, accompanied by embedded mid-level
impulses, will traverse the periphery of the upper ridge and
overspread the West Coast toward the northern Rockies. This belt of
stronger flow aloft will support dry and windy conditions supportive
of wildfire spread, with deep-layer ascent associated with embedded
impulses also supporting dry thunderstorm initiation, especially
over portions of Montana.

...Parts of the northern Sierra to the northern Rockies...
Through the afternoon, a dry boundary layer will mix upward to the
mid-levels, allowing for downward momentum transport of the
aforementioned stronger mid-level flow aloft. By afternoon peak
heating, sustained southwesterly surface winds exceeding 20 mph
should become widespread, especially in terrain favoring areas, from
the northern Sierra to the northern Rockies. Fifteen percent RH
should be common by afternoon peak heating, overlapping with many
areas experiencing 20+ mph sustained winds, warranting widespread
Critical highlights given dry fuels.

...Portions of Montana...
Guidance consensus (including high-resolution members) depicts at
least scattered thunderstorm development across much of Montana by
afternoon as a mid-level impulse overspreads the region. Forecast
soundings show classic inverted-v profiles extending up to 500 mb,
amid appreciable flow aloft. As such, fast-moving and high-based
storms will promote dry lightning strikes over fuel beds receptive
to fire spread, warranting isolated dry thunderstorm highlights.
Furthermore, strong vertical wind shear will accompany the mid-level
impulse, and given appreciable buoyancy aloft, several of these
storms may produce strong to severe wind gusts, which may exacerbate
any ongoing fires or holdovers. Please see the latest Day 1
Convective outlook for more details on the severe thunderstorm
threat.

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

$$