U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 190538
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1238 AM CDT Sat Jul 19 2025
Valid 191200Z - 201200Z
...Synopsis...
Upper-level ridging will persist across much of the southern half of
the U.S. today. A weak upper-level low will be positioned over
southern California into northern Baja. A belt of stronger mid-level
winds will exist across the northern tier states with a
low-amplitude shortwave trough moving through the Northwest. A
surface trough will deepen in the lee of the northern Rockies.
...Columbia Basin into the northern Great Basin...
Offshore high pressure and the deepening trough to the east will
promote modestly strong westerly winds across the Cascades. Winds in
the Columbia Basin will reach 15-20 mph with perhaps higher speeds
within some of the Cascade gaps. RH of 15-20% is possible by the
afternoon.
In the northern Great Basin, surface winds of 15-20 mph are possible
with RH falling into the 10-20% range. Stronger winds are possible
in the Snake River Plain as mid-level winds will be stronger and
better aligned with the terrain. There, up to 25 mph winds will be
possible for a short duration.
..Wendt.. 07/19/2025
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 190540
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1240 AM CDT Sat Jul 19 2025
Valid 201200Z - 211200Z
...Synopsis...
The upper-level pattern on Sunday will be similar to Saturday.
However, stronger mid-level flow may nudge southward as the upper
trough amplifies through the period in the Northwest. Surface
troughing will develop in the northern High Plains.
...Northern Great Basin...
Another day of elevated fire weather can be expected. With the
stronger mid-level winds extending more to the south, greater
spatial coverage of at least briefly 20+ mph winds may occur.
Overall, however, 15-20 mph winds will be most common. RH of 10-20%
will be possible in Nevada while Idaho will more likely see 15-20%
by the afternoon. Model guidance does show some potential for high
cloud cover which could also limit the duration of critical
conditions. Ensemble guidance shows low probability of sustained
critical conditions likely on account of those uncertainties.
..Wendt.. 07/19/2025
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 182041
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0341 PM CDT Fri Jul 18 2025
Valid 201200Z - 261200Z
A mid/upper-level tough is forecast to deepen across the Pacific
Northwest Day 3/Sunday into Day 4/Monday. Thereafter, the evolution
of the trough is somewhat uncertain, largely due to
inter/intra-model variability. Though, many recent solutions now
suggest some form of splitting with a portion of the trough ejecting
across the northern Rockies and another becoming cutoff (or
redeveloping) off/near the coast of California/Oregon through the
remainder of the week.
...Day 3/Sunday - Day 5/Tuesday: Wind/RH...
Increasing mid-level winds - associated with the aforementioned
trough - will promote a broadening area of dry/breezy southwesterly
flow Day 3/Sunday across portions of the northern Great Basin, far
northeastern California, southeastern Oregon, and southwest Montana.
At this time, locally critical conditions appear most likely across
wind-prone areas of the Snake River Plain in Idaho.
Fire weather conditions are forecast to shift a bit southward while
also increasing in coverage and intensity Day 4/Monday, as the
aforementioned trough continues to deepen. While an area of critical
fire weather conditions appears probable, relatively poor run-to-run
model consistency precludes increasing critical probabilities to 70%
at this time.
Dry/breezy conditions are forecast to linger into Day 5/Tuesday
across the Great Basin. Though, relaxing mid-level winds and reduced
surface pressure gradients should promote lighter surface winds and
locally elevated fire weather conditions.
...Day 4/Monday - Day 5/Tuesday: Dry Thunderstorms...
Isolated dry thunderstorms are possible Day 4/Monday into Day
5/Tuesday across portions of northern Great Basin, Northwest, and
northern Rockies, as increasing moisture associated with the
aforementioned trough impinges on the area. While forecast guidance
suggests precipitable water values may be relatively high (0.8 - 1+
inch), somewhat fast-moving storm motions and critically receptive
fuels suggest a mix of wet/dry modes. At this time, uncertainty
remains too large to introduce probabilities for dry thunderstorms.
..Elliott.. 07/18/2025
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