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U.S. & Canada 00-UTC 48 Hour Surface Smoke Forecast
Map is in operation from early April through October 31
U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 231639
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1139 AM CDT Thu Jul 23 2026
Valid 231700Z - 241200Z
...17z Update...
The prior forecast remains valid with no changes. Isolated severe
gusts are possible in and around where the Day 1 Marginal severe
Risk overlaps with the Dry Thunderstorm probabilities. See the
previous discussion for more information.
..Nauslar/Lyons.. 07/23/2026
.PREV DISCUSSION... /ISSUED 1222 AM CDT Thu Jul 23 2026/
...Synopsis...
Upper-level troughing will continue across the eastern U.S. as
surface high pressure builds into the Ohio Valley. A long-lived
upper ridge across the western U.S. will finally begin to flatten
and break down owing to an approaching eastern Pacific upper trough.
Within the last 24 hours, mixed wet/dry thunderstorms have traversed
portions of central Oregon and the Cascades. Only localized areas
received appreciable precipitation, not fully mitigating fuel
concerns across the broader environment. Returning dry and windy
conditions east of the Cascades will further enhance the fuelscape,
encouraging lightning-induced ignitions to emerge and further
exacerbating numerous wildfires across the region.
...Pacific Northwest and Northern Rockies...
As upper-level flow transitions from broadly southerly to
southwesterly, monsoonal moisture will be shunted northeastward as a
dry airmass returns to the Inland Northwest. Daytime
destabilization, ample mid-level moisture, and fast storm motions
over the Columbia Basin into the Northern Rockies will promote
isolated wet/dry thunderstorms. In addition, preceding days of hot
and dry conditions has allowed fuels to approach critical
thresholds, making the environment increasingly receptive to new
ignitions. As upper level flow strengthens and impinges upon the
Northwest, tightening surface pressure gradients along the Cascades
will promote very gusty winds amid a dry boundary layer. Elevated
highlights have been maintained where RH values will decline to less
than 20% as winds increase to 15-20 mph (localized gusts up to 35
mph in terrain-favored areas). Greater concern for new ignitions and
impacts to ongoing fires exist where the Elevated and Isolated Dry
Thunderstorm highlights overlap.
...Southern Plains...
A mid-level shortwave trough will track across the High Plains this
afternoon as a surface low emerges over the Oklahoma/Texas
Panhandles. At peak heating, 15-20% RH will combine with
southwesterly winds of 10-15 mph atop a mixed fuelscape. Pockets of
cured grasses and ERCs approaching the 80-90th percentile will
promote locally elevated fire concerns.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 230525
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1225 AM CDT Thu Jul 23 2026
Valid 241200Z - 251200Z
...CRITICAL FIRE WEATHER AREA FOR NORTHEASTERN
CALIFORNIA...NORTHWESTERN NEVADA...AND SOUTH-CENTRAL/SOUTHEASTERN
OREGON...
...Synopsis...
Upper-level ridging will begin to transition towards the central
U.S. as eastern Pacific troughing approaches the Pacific Northwest.
Meanwhile, troughing will persist across the eastern U.S. with
several embedded shortwaves providing unsettled conditions in the
Midwest and portions of the Southeast.
Enhanced southwesterly flow will overspread the Pacific Northwest,
Northern Rockies, and the Montana Plains on Day 2/Friday, bringing
hot, dry, and windy conditions to a mostly dry fuelscape. With
preceding days of mixed wet/dry thunderstorms and abundant lightning
being followed by such meteorological conditions, holdover ignitions
are likely to emerge. Daytime RH values of less than 20% are
expected to combine with southwest-westerly sustained winds of 15-20
mph, warranting Elevated highlights. While some pockets of heavier
rainfall from prior days thunderstorms may alleviate localized fuel
concerns, the expansive environment is approaching, or has already
reached, critical fuel thresholds. A Critical risk area was
introduced across northeastern California, northwestern Nevada, and
south-central/southeastern Oregon where 15-25 mph southwesterly
winds and less than 15% RH will overlap 80-90th percentile ERCs.
Critical winds/RH are likely to develop across portions of
north-central and northeast Montana as well, but these conditions
will likely act as more of a curing event.
..Elizalde-Garcia.. 07/23/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 222143
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0443 PM CDT Wed Jul 22 2026
Valid 241200Z - 301200Z
Upper-level troughing will develop over the Pacific Northwest into
the northern Rockies late this week through the weekend. Mid-level
southwest-westerly flow of 30-60 knots will overspread the region
with a tightening onshore pressure gradient and lee troughing east
of the Cascades and northern Rockies. The Four Corners High will
likely slowly shift east-southeast towards the southern High Plains,
with daily monsoonal thunderstorms remaining likely across the
greater Four Corners region into early next week.
...Northwestern US...
Overall, a critical fire weather pattern will continue to unfold
through the weekend across the northwestern US with lightning
followed by hot, dry, and windy conditions. Elevated to critical
fire weather conditions are expected across the Inland Northwest,
northwest Great Basin, and extending through northern Montana Day
3/Friday as west-southwest winds strengthen amid a drying and
warming airmass. Critical winds/RH are likely to develop across
portions of north-central and northeast Montana, but this will
likely act more as a curing event.
Winds will strengthen on Day 4/Saturday across the Inland Northwest
and into northwest Montana, with critical conditions expected again
here and from south-central/southeast Oregon extending into
northeast California, northwest Nevada, and southwest Idaho.
Isolated to scattered mixed wet/dry thunderstorms are likely in
portions of central Montana on Day 4/Saturday, but there remains too
much uncertainty regarding the overlap of receptive fuels and drier
thunderstorm development to include dry thunderstorm probabilities
at this time. However, dry and breezy conditions are likely across
portions of western/central Montana Day 4/Saturday.
Dry and breezy conditions will continue from the northwest Great
Basin through central/southern Idaho into Montana on Day 5/Sunday
and possibly Day 6/Monday. There remains forecast uncertainty
regarding lingering dry and breezy conditions across portions of the
Inland Northwest, and the likelihood of critical conditions in
portions of the northwest Great Basin and northern Montana. Much of
this depends on the evolution of the upper-level troughing over the
northwest US. Another source of forecast uncertainty is how areas
that currently have less receptive fuels in portions of northeast
Nevada, central/eastern Idaho, and southwest Montana will respond to
multiple consecutive days of hot, dry, and breezy conditions.
...Plains...
Hot, dry, and breezy conditions will likely develop across portions
of the Plains during the outlook period. Fuels, especially fine
fuels, will begin to cure and perhaps rapidly. How this pattern
affects these areas will continued to be monitored.
..Nauslar.. 07/22/2026
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