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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 011700
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1200 PM CDT Sat Aug 01 2026
Valid 011700Z - 021200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE COLUMBIA
BASIN IN CENTRAL/SOUTHEASTERN WASHINGTON AND NORTHERN OREGON...
...CRITICAL FIRE WEATHER AREA FOR EASTERN OREGON AND FAR WESTERN
IDAHO INTO EASTERN WASHINGTON...THE IDAHO PANHANDLE...AND
NORTHWESTERN/NORTH-CENTRAL MONTANA...AND THE SNAKE RIVER PLAIN OF
EASTERN IDAHO...
***Dangerous fire weather conditions are expected across
central/southeastern Washington and northern Oregon today.***
...Inland Northwest into western and central Montana...
No changes have been made to the highlights across this region.
Surface winds at 16Z have already increased to 15-25 mph with gusts
near 30 mph across portions of the Columbia Basin and north-central
Oregon, several hours ahead of the expected afternoon maximum. Along
the Rocky Mountain Front, west winds of 30-45 mph with gusts to 60
mph (locally near 75 mph) are expected to develop this evening and
peak between 9 PM and 6 AM MDT as mountain wave activity
strengthens. Fire weather concerns should continue through the night
into Sunday morning due to lingering breezy conditions coupled with
poor overnight RH recoveries.
...Eastern Idaho...
Critical fire weather highlights have been expanded across the Snake
River Plain and the adjacent central Idaho mountains. While there
had been some uncertainty regarding recent rainfall and its impact
on fuels, observations suggest rainfall across eastern Idaho was
generally less than 0.10 inches and was associated with dry
thunderstorms (several of which produced ignitions that remain
active). West to southwest surface winds will increase to near 20
mph (gusts to 30 mph) this afternoon, amid minimum RH reductions of
near 10-15%, supporting the Critical expansion. The lowest RH is
expected across the Upper Snake River Valley and the Lemhi and Lost
River ranges, where single digits may persist for several hours.
...Eastern Montana...
Elevated highlights have been expanded east across northeast
Montana. Very hot afternoon temperatures near 100 F will support
minimum RH reductions near 15-20%, with the lowest values over the
western portions of the area and higher RH farther east (where fuels
are also less receptive). While surface winds should remain modest
through the afternoon (generally 10-15 mph), northwesterly winds
will increase to 15-25 mph with gusts to 35 mph behind the front
late tonight, with poor overnight RH recovery.
Widespread wildfire smoke continues across eastern Oregon, eastern
Washington, and central and western Idaho.
Please see the previous discussion below for more information.
..Elliott.. 08/01/2026
.PREV DISCUSSION... /ISSUED 0216 AM CDT Sat Aug 01 2026/
...Synopsis...
***Dangerous fire weather conditions are expected across
central/southeastern Washington and northern Oregon today.***
Upper-level ridging will remain in place from the Desert Southwest
into the northern High Plains today as a potent upper-level trough
moves onshore across the Pacific Northwest and British Columbia.
Simultaneously, a surface low will amplify across southern Alberta
as a dry cold front progresses rapidly east-southeastward through
the Pacific Northwest and northern Rockies. This setup will foster
widespread elevated to critical fire weather concerns across an
expansive area of the eastern Pacific Northwest, northern Rockies,
and northern Great Basin, with extremely critical conditions
forecast for portions of the Columbia Basin in central/southeastern
Washington and northern Oregon.
...Central/southeastern Washington into northern Oregon...
As the aforementioned upper trough begins to move onshore across the
Pacific Northwest, southwesterly surface winds will begin to
increase ahead of the approaching dry cold front, likely
accelerating to 20-25 mph as RH begins to decline. The cold front is
then expected to move through the region by late morning/early
afternoon, with an accompanying wind shift to broadly westerly (and
perhaps to west-northwesterly later in the evening). Concurrently,
stronger mid-level flow (35-45 kt at 700 mb) will overspread the
region and gradually attain a more perpendicular orientation
relative to the Cascades. In conjunction with a tightening surface
pressure gradient, this will foster a favorable environment for very
strong, dry downslope flow in the lee of the Cascades, with
sustained westerly winds increasing to 30+ mph (strongest in the lee
of the immediate foothills and in favored terrain/gap flow areas),
gusts increasing to 40-50+ mph, and RH falling to 5-15%.
ERCs are commonly approaching or exceeding the 95th percentile, and
a few large wildfires are already ongoing across this region. This
combination of meteorological and fuel conditions will support
extremely critical fire weather conditions (with winds potentially
exceeding 25+ mph for up to 6 hours in some locations) across
portions of the Columbia Basin in central/southeastern Washington
and northern Oregon this afternoon and evening. While eventual RH
increases are expected later tonight, a longer duration of elevated
wind conditions (15+ mph) is also forecast, potentially lasting
12-14 hours for some locations. Only a minor expansion of the
northwestern edge of the extremely critical area was made with this
outlook cycle.
A broader area of elevated to critical fire weather conditions is
forecast farther south from northeastern California and northern
Nevada into much of central/eastern Oregon and western Idaho. Across
this region, sustained surface winds of 15-25 mph are expected to
overlap very low RH of 5-20% and ERCs above the 90th to 98th
percentiles.
...Northwestern and north-central Montana...
As the upper trough transitions eastward through the day,
strengthening mid-level flow will overspread the northern Rockies,
with a 55-65+ kt 700 mb jet emerging along the Rocky Mountain front
of northern/central Montana. This will favor strong, westerly
downslope winds of up to 30+ mph (and gusts of 50+) beginning during
the afternoon (21-00 UTC) and persisting through the overnight
hours. RH values will initially range from 10-20% in the afternoon
and increase to 20-35% overnight amid ERCs at the 99th percentile,
supporting critical to potentially locally extremely critical fire
weather conditions across portions of northwestern and north-central
Montana.
During the afternoon, southwesterly surface winds of 10-15 mph and
RH values of 10-15% will also promote elevated fire weather concerns
across much of central Montana. While RH will increase to 15-25%
overnight, a stronger northwesterly surge (15-25 mph sustained with
gusts to 30-40+ mph) will accompany the passage of the cold front
during the overnight hours.
...Central Idaho into the Snake River Plain...
Ahead of the cold frontal passage, southwesterly surface winds will
strengthen to 15-20 mph (locally stronger) amid very low RH around
10%. While recent rainfall across eastern Idaho precludes the
expansion of Critical highlights, these conditions are expected to
support elevated to locally critical fire weather concerns this
afternoon across central Idaho and the Snake River Plain. In
addition, this will likely serve as a preconditioning-style event
leading into expansive critical fire weather concerns on D2/Sunday.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 011957
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0257 PM CDT Sat Aug 01 2026
Valid 021200Z - 031200Z
...CRITICAL FIRE WEATHER AREA FOR FAR NORTHERN
UTAH...WESTERN/CENTRAL WYOMING...CENTRAL/EASTERN IDAHO...AND
MONTANA...
...Wyoming...
Critical fire weather highlights have been expanded east across the
Bighorn and Wind River Basins and the adjacent mountains of central
Wyoming. Minimum RH values are forecast between 5 and 15%, with the
lowest values expected across central Wyoming amidst afternoon high
temperatures in the upper 80s to upper 90s. West to northwest
surface winds are forecast to increase to near 20 mph (gusts to 35
mph) by midday across southwest Wyoming and the Green River Basin
and later farther east.
...Elsewhere...
Elevated highlights have also been expanded across portions of
southwestern Utah and western Colorado. Southwest winds of 10-20 mph
(gusts near 35 mph) are expected amidst minimum RH near 8% across
southwestern Utah. Winds should be weaker across western Colorado,
but breezy winds coupled with hot and dry conditions over receptive
fuels support elevated fire weather concerns.
While minimum RH of 5-13% is expected across northern Nevada behind
the front, northerly winds of 10-20 mph should preclude Critical
highlights. Farther east, minimum RH of 5-15% is expected across the
Nebraska Panhandle and adjacent Wyoming High Plains ahead of a lee
trough. While sustained winds should generally remain around 15-20
mph, frequent wind gusts to 35-45 mph will still support rapid fire
spread with locally critical fire weather conditions possible.
Fuels remain receptive across the outlook area, with ERCs at or
above the 95th percentile in most locations and near the 98th
percentile across north-central Montana, supporting high fire
intensity and resistance to control on new ignitions.
Please see the previous discussion below for more information on
tomorrow's fire weather forecast.
..Elliott.. 08/01/2026
.PREV DISCUSSION... /ISSUED 0223 AM CDT Sat Aug 01 2026/
...Synopsis...
The strong upper-level trough positioned across the Pacific
Northwest/northern Rockies will transition slowly east-northeastward
on D2/Sunday, with strong mid-level flow persisting across the
region and a dry cold front continuing to progress
east-southeastward across the region. A combination of dry and windy
conditions within the post-frontal air mass and hot, dry, and windy
conditions ahead of the front will promote widespread elevated to
critical fire weather concerns across portions of the Great Basin,
Pacific Northwest, northern Rockies, and northern Great/High Plains.
Potential also exists for lightning-induced holdovers to emerge from
thunderstorms earlier in the week across portions of eastern Idaho
and southwestern Montana.
...Montana into the northern Great Plains...
Latest model guidance suggests a dry cold front should extend across
eastern Montana south-southwestward into northern Wyoming and
eastern Idaho at the start of the D2 period (12 UTC Sunday). Strong
mid-level flow (35-45 kts at 700 mb) is forecast to persist along
the Montana/Canada border during this time frame. Coupled with a
tightened surface pressure gradient within the post-frontal air
mass, this will favor strong westerly downslope flow across much of
central/northern Montana (increasingly northwesterly with eastward
extent) beginning early in the period on Sunday. Sustained 20-25 mph
winds are forecast to be common Sunday morning, with these
magnitudes persisting across northern/central Montana but weakening
to 15-20 mph or less across eastern Montana, western SD/ND, and
northeastern Wyoming. Wind gusts to 30-40+ mph will also be possible
(primarily across Montana), with the strongest gusts most likely
Sunday morning. In addition, RH recoveries are forecast to be modest
at best Saturday night into Sunday morning, which should favor quick
RH reductions to 15-20% by late morning/early afternoon Sunday
(locally dropping to 10% later Sunday afternoon).
With ERCs commonly exceeding the 90th and 95th percentiles (98th
percentile in central/north-central Montana), these conditions will
promote an extended period (6+ hours for some locations) of critical
fire weather conditions. The Critical highlights were expanded
slightly eastward in portions of east-central Montana with this
update. The forecast for sustained winds of around 15 mph precludes
farther eastward expansion into North Dakota at this time, but
elevated fire weather concerns are still expected across this
region. Additionally, some guidance suggests a secondary cold front
may pass through portions of north-central Montana later Sunday
night, which could bring a shift to northwesterly winds and a brief
surge in magnitude. This will be monitored for future outlooks.
Farther southeast, sustained southerly winds of around 15 mph and RH
reductions to 15-20% are forecast across portions of western South
Dakota and northwestern Nebraska, which will promote elevated fire
weather concerns. A shift to north-northwesterly winds is expected
with the passage of the southeastward progressing cold front through
the afternoon/evening.
...Central/eastern Idaho into western Wyoming...
Recent forecast guidance suggests the dry cold front is likely to
extend from northern Wyoming into eastern/southeastern Idaho early
in the period on Sunday. Within the post-frontal air mass, generally
westerly surface winds are forecast to funnel down the Snake River
Valley, with magnitudes up to 25 mph (perhaps higher) for at least 6
hours amid RH reductions to 15-20%. Farther east in western Wyoming,
initially southwesterly surface winds ahead of the front will shift
to westerly and accelerate to around 20 mph amid RH of 10-20%. While
portions of these areas have received recent rainfall, ERCs are
already noted to be around the 80-95th percentiles, and dry and
breezy conditions on D1/Saturday will aid in the drying of fine
fuels. Thus, this combination of winds, RH, and dry fuels will
promote critical fire weather concerns from central/eastern Idaho
into western Wyoming beginning late morning/early afternoon on
Sunday. Lighter winds around 15-20 mph should also support elevated
fire weather conditions across portions of central Wyoming.
...Eastern Washington/Oregon and northern Idaho...
Lingering, enhanced mid-level flow across the eastern portions of
the Pacific Northwest (including eastern WA/OR and northern ID) may
support sustained westerly/northwesterly winds up to around 15 mph
Sunday afternoon, with minimum RH values forecast to range from
20-25% (eastern WA, northern ID, and northern OR) to 10-20%
(southeastern OR). This may promote several hours of elevated fire
weather concerns on Sunday across areas that are forecast to
experience critical to extremely critical fire weather conditions on
D1/Saturday.
...Great Basin...
Westerly/southwesterly sustained surface winds are forecast to
increase to around 15 mph amid very low RH of around 10% Sunday
afternoon. Combined with ERCs generally ranging from the 80th to
95th percentiles across the region, this is expected to support at
least a few hours of elevated fire weather concerns across much of
eastern/northern Nevada and western/northern Utah Sunday afternoon.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 012159
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0459 PM CDT Sat Aug 01 2026
Valid 031200Z - 091200Z
...Synopsis...
An upper-level trough over southwestern Canada will move southeast
across the northern Rockies and into the northern Plains on Day
3/Monday. Meanwhile, a strong cold front is forecast to sweep across
the Dakotas Monday morning, the central High Plains during the
afternoon, and then across southeastern Colorado and western Kansas
Monday night. Upper-level ridging will remain ahead of the front
across the central and southern Plains, keeping hot and dry
conditions in place through Monday afternoon.
The trough will move slowly east across the northern Plains and the
upper Midwest Day 4/Tuesday and Day 5/Wednesday, with northwesterly
flow aloft and a cooler airmass following across the northern and
central Plains. Monsoonal moisture should spread back north across
the Four Corners as high pressure rebuilds to the south, and wetting
rainfall will become more common across much of the interior
Southwest.
Upper-level ridging is then expected to rebuild across the western
states by Day 6/Thursday and persist into next weekend, with hot and
dry conditions across the Great Basin, northern Rockies, and High
Plains. Guidance differs on how far inland the ridge builds and on
the strength of disturbances moving through the northwesterly flow
downstream, with run-to-run consistency remaining poor late in the
period.
...Day 3/Monday...
A deeply mixed and much drier airmass is forecast behind the front,
with strong north to northwest surface winds developing across
Wyoming and the western Dakotas. Ahead of the front, hot, dry, and
breezy conditions will continue across the High Plains into eastern
Colorado and western Kansas. A 40% probability for Critical fire
weather conditions was maintained across the northern Great Basin
and expanded eastward across these areas, with fuels remaining
receptive across most of the outlook area.
Fire weather concerns are forecast to be greatest across the
northern portion of the area, where the strongest post-frontal winds
will accompany the driest air. Farther south, afternoon humidity
will be very low, but sustained winds are less certain. Farther
west, hot and dry conditions will continue across the Snake River
Plain and northern Great Basin with lighter winds.
Isolated thunderstorms may develop along and ahead of the front
across the central High Plains Monday afternoon and evening. With
very dry low-level air in place, any storms that develop could
produce lightning with little wetting rainfall. While confidence
remains low, a dry thunderstorm area may be needed in a future
outlook.
...Day 4-5/Tuesday-Wednesday...
Fuels will remain dry across the Great Basin, northern Rockies and
High Plains, where afternoon humidity should remain low and breezy
winds at times may support locally elevated fire weather conditions.
Critical probabilities were not introduced due to limited coverage.
Elsewhere, cooler conditions behind the front and a chance of
showers and thunderstorms should limit fire weather concerns across
the northern and central Plains.
...Day 6-8/Thursday-Saturday...
Fuels will remain receptive across the Great Basin, northern Rockies
and High Plains late next week. Sustained winds should generally
remain modest, though some guidance brings a disturbance toward the
Pacific Northwest by next weekend, which would increase wind
potential across the northern Rockies and northern Plains.
Confidence at this range is low.
..Elliott.. 08/01/2026
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