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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 021649
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1149 AM CDT Sun Aug 02 2026
Valid 021700Z - 031200Z
...CRITICAL FIRE WEATHER AREA FOR FAR NORTHERN
UTAH...WESTERN/CENTRAL WYOMING...CENTRAL/EASTERN IDAHO...AND
MONTANA...
...Central and Eastern Montana...
No changes have been made to the Critical highlights across the
region. Surface observations at 1600Z show sustained northwest winds
have already increased to near 20-25 mph at Fort Belknap and
Glendive, and to near 25 mph at Cut Bank, with surface dewpoints
generally in the 30s F across eastern Montana. Critical fire weather
conditions should continue through the afternoon and evening as
sustained winds near 20-25 mph (with stronger gusts) overlap minimum
RH values of 10-15% and critically receptive fuels. The most
persistent conditions are expected along the Hi-Line and across the
Judith Basin.
...Dry Thunderstorms - Central and Northeastern Montana into far
western North Dakota...
An isolated dry thunderstorm area has been introduced across central
and northeastern Montana into far western North Dakota. Isolated -
potentially high-based - thunderstorms may develop later this
afternoon into this evening along and east of the Divide as the
front moves east. Little wetting rainfall is expected, and any
lightning would occur over critically receptive fuels, with ERC
values in excess of the 95th percentile. New ignitions are also
possible on the periphery of thunderstorm cores, and gusty and
erratic outflow winds may also affect fire behavior on any ongoing
fires. Confidence in storm coverage and timing is low.
...Eastern Idaho...
No changes have been made to the Critical highlights across the
Snake River Plain. Surface observations at 1600Z show sustained
southwest winds of 20-25 mph in place at Pocatello and Idaho Falls,
with locally stronger wind speed across the upper Plain. Several
hours of critical fire weather conditions are expected this
afternoon as these winds overlap minimum RH values near 10-15% and
critically receptive fuels.
...Wyoming Basins...
No changes have been made to the Critical highlights across
southwest Wyoming and the Wind River and Bighorn Basins. Sustained
winds near 20 mph should overlap minimum RH values of 5-15% and
critically receptive fuels through the afternoon and early evening.
Fuels are most receptive across the Wind River and Bighorn Basins,
where ERC values exceed the 95th percentile.
...Northern and Central High Plains...
Sustained winds near 20 mph are forecast to overlap minimum RH
values near 20% across the western Nebraska Sandhills and from
southwest North Dakota into adjacent southeast Montana this
afternoon. While locally critical fire weather conditions will be
possible in both areas, these conditions appear too brief/spotty to
upgrade to Critical. Nevertheless, any fires in these areas could
exhibit rapid growth/spread given ERC values near the 95th
percentile.
Please see the previous discussion below for more information on
today's fire weather forecast.
..Elliott.. 08/02/2026
.PREV DISCUSSION... /ISSUED 0200 AM CDT Sun Aug 02 2026/
...Synopsis...
The strong upper-level trough positioned across the Pacific
Northwest/northern Rockies will translate slowly eastward today,
with strong mid-level flow remaining in place and a dry cold front
progressing east-southeastward across the region. Dry/windy
conditions within the post-frontal air mass and hot, dry, and windy
conditions ahead of the front will promote an expansive area of
elevated to critical fire weather concerns across portions of the
Great Basin, Pacific Northwest, northern Rockies, and northern
Great/High Plains.
...Montana into the northern Great Plains...
Latest guidance still indicates that a dry cold front will extend
from northeastern Montana southwestward into northern Wyoming and
eastern Idaho at the start of the period (12 UTC) today, with lee
troughing extending southward into eastern Wyoming and Colorado.
Winds behind this front/lee trough are forecast to be commonly 15-25
mph Sunday morning from northeastern Wyoming into eastern and
northern Montana, with the direction varying from westerly (northern
Montana) to northerly (northeastern Wyoming). Enhanced mid-level
flow (35-45+ kts at 700 mb) lingering along the Montana/Canada
border will support the continuation of sustained westerly surface
winds of 20-25 mph across northern Montana into the evening, with
northwesterly winds forecast to weaken to near 15 mph farther east
into the northern Great Plains (western ND/SD and northeastern WY)
by mid afternoon. While wind gusts should weaken through the day,
gusts to 30-40 mph (locally up to 50-60 mph in the immediate lee of
the Rockies) will also be possible, particularly across Montana this
morning. In addition, RH values are noted to range from 10-25%
across much of Montana as of 530 UTC Sunday, with only modest
recoveries expected prior to the start of the period at 12 UTC. This
will favor quick RH reductions to 15-20% by late morning/early
afternoon on Sunday (locally dropping to 10% later Sunday
afternoon). With ERCs commonly exceeding the 90th and 95th
percentiles (98th percentile in northern Montana), these conditions
will promote an extended period (6+ hours for some locations) of
critical fire weather conditions, with elevated fire weather
concerns forecast farther east into the northern Great Plains.
Elevated fire weather concerns are also forecast ahead of the lee
trough from the KS/CO/NE border vicinity northward into central SD
where sustained southerly winds of 15-20 mph are forecast to overlap
minimum RH values of 15-25% this afternoon.
Finally, guidance also suggests a secondary cold front may progress
into portions of northern Montana by the end of the period, bringing
a shift to northwesterly winds and the potential for at least a
brief period of sustained 15-20 mph winds (with potential for
occasional gusts of 30-35 mph).
...Central/eastern Idaho into western/central Wyoming...
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 locally higher) for up to 6+ hours in some
locations amid RH of 10-20%. Farther east, initially southwesterly
winds across western/central Wyoming will accelerate to 20-25 mph
and become more westerly amid RH reductions to 10-20%. While
portions of these areas have received recent rainfall, ERCs are
already noted to be around the 80th to 95th percentiles or greater,
and preceding dry/breezy conditions on Saturday likely aided in the
curing of fine fuels. Thus, this combination of winds, RH, and fuels
will support several hours of critical fire weather concerns from
central/eastern Idaho into western/central Wyoming beginning late
this morning/early this afternoon.
...Eastern Washington/Oregon and northern Idaho...
Lingering, enhanced mid-level flow across the eastern portions of
the Pacific Northwest may support sustained westerly/northwesterly
downslope flow up to around 15 mph (locally to 20 mph) with
occasional gusts to 25-30 mph, primarily in favored gap/terrain flow
areas in the immediate lee of the Cascades. Minimum RH values are
also forecast to range from 20-25% (eastern WA/northern ID) to
10-20% (southeastern Oregon). This is expected to promote at least a
few hours of elevated fire weather concerns this afternoon across
areas that experienced critical to extremely critical fire weather
conditions on Saturday.
...Great Basin...
Sustained surface winds ranging from westerly
(central/western/northern Nevada and northern Utah) to southwesterly
(southern/southeastern Nevada and southwestern Utah) are forecast to
increase to around 15 mph (locally up to 20 mph) across portions of
the Great Basin this afternoon. RH values are forecast to fall to
5-15% across much of this region, with ERCs noted to range from the
80th to 95th percentiles. These conditions will support at least a
few hours of elevated fire weather concerns. The Elevated highlights
were expanded westward to near the Nevada/California border with
this outlook issuance to reflect the latest trends in guidance/HREF
probabilities.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 021943
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0243 PM CDT Sun Aug 02 2026
Valid 031200Z - 041200Z
Tomorrow's (Monday) fire weather forecast remains on-track, with no
changes needed to the Elevated fire weather area based on the latest
guidance.
...High Plains...
Sustained winds near 20 mph are expected to overlap minimum RH
values of 15-20% and critically receptive fuels (ERC values near or
above the 95th percentile) from tomorrow afternoon into the evening
across the High Plains - from the Texas and Oklahoma Panhandles
north through eastern Colorado, northwest Kansas and southwest
Nebraska into western South Dakota. The strongest winds are forecast
across western South Dakota, where sustained wind speeds are
expected to increase through the day and peak near 25-30 mph during
the late afternoon. While locally critical conditions are possible,
these conditions appear to be too spotty to upgrade to Critical at
this time.
...Wyoming Basins...
Meteorological critical fire weather conditions are expected for
several hours tomorrow afternoon and early evening across the Green
River Basin and vicinity, as sustained winds near 20 mph overlap
minimum RH values near 10%. However, these conditions are largely
expected where the fuel loads are low, precluding the introduction
of a Critical fire weather area. Nevertheless, locally critical fire
weather conditions are possible where fuels are more continuous.
Farther north and east, sustained winds of 15-25 mph should overlap
minimum RH values of 15-20% and critically receptive fuels across
the Wind River, Bighorn, and Powder River Basins into northeastern
Wyoming.
...Dry Thunderstorms...
Isolated high-based thunderstorms are expected to develop along the
front from eastern Colorado into western Nebraska late tomorrow
afternoon. While little wetting rainfall is expected and
lightning-induced ignitions are possible, confidence in coverage
during the afternoon precludes an Isolated Dry Thunderstorm area at
this time. Thunderstorm coverage is forecast to increase tomorrow
evening into overnight (as RH values recover), with a nearby
Marginal severe weather threat (see the SPC Day 2 Convective Outlook
for more information).
Please see the previous discussion below for additional information
on tomorrow's fire weather forecast.
..Elliott.. 08/02/2026
.PREV DISCUSSION... /ISSUED 0204 AM CDT Sun Aug 02 2026/
...Synopsis...
Upper-level troughing will remain in place across the northern
Rockies and northern High/Great Plains on D2/Monday, with enhanced
mid-level westerly flow extending from the northern Great Basin into
the northern Great Plains. A mid-level shortwave trough embedded
within this westerly flow will translate quickly eastward, ejecting
into the northern Great Plains by Monday evening. This will aid in
the northeastward progression of a surface low across the Dakotas,
with a trailing cold front simultaneously progressing southeastward
across the central High/Great Plains and lee troughing extending
farther south across eastern Colorado. Dry and breezy conditions
both within the post-frontal air mass and preceding the front are
expected to support a broad area of elevated fire weather concerns
from the northern Great Basin into portions of the High/Great Plains
on Sunday.
...Northern Great Basin into the High/Great Plains...
Sustained northwesterly to northerly (perhaps even northeasterly
across portions of central Wyoming) winds of 15-20 mph are forecast
amid minimum RH values of 15-25% across eastern/northern Wyoming,
southeastern Montana, the western Dakotas, and the Nebraska
Panhandle within the post-frontal air mass Monday afternoon. To the
southwest, westerly to northwesterly sustained winds of 15-25 mph
and very low RH of 10-15% are forecast to extend from northeastern
Nevada/central Idaho into northern Utah, northwestern Colorado, and
southwestern Wyoming. To the south, sustained southerly winds of
15-20 mph and minimum RH values of 15-25% are forecast across
portions of the central/southern High Plains preceding the
aforementioned cold front and lee trough. Despite recent rainfall
across portions of this region, fuels are noted to commonly exceed
the 80th to 90th percentiles (95th percentile in some locations).
This combination of meteorological and fuel conditions will support
widespread elevated fire weather concerns Monday afternoon, with
locally critical conditions possible across portions of
southwestern/south-central Wyoming where winds are forecast to be
the strongest. The primary change with this outlook cycle was to
expand the Elevated highlights southward across portions of the
southern/central High Plains based on recent HREF wind/RH
probability trends. While elevated wind/RH criteria are likely to be
met farther west into the western TX/OK Panhandles and portions of
eastern NM, greater recent rainfall accumulations preclude an
expansion of the Elevated highlights into these areas at this time.
...Central High Plains, including northern Colorado...
Isolated, high-based thunderstorms may develop ahead of the
approaching cold front and along the high-terrain of
central/northern Colorado Monday afternoon. Forecast soundings
depict deep, well-mixed boundary layers with LCLs of 4+ km and PW of
0.5-0.75". These profiles suggest that any storm that develops could
produce lightning with little wetting rainfall. While an isolated
lightning ignition may be possible, confidence remains low in more
than an isolated thunderstorm overlapping drier, more receptive
fuels currently noted across northern/northeastern Colorado. Trends
will be monitored for future outlook cycles, however.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 022134
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0434 PM CDT Sun Aug 02 2026
Valid 041200Z - 101200Z
A mid-level trough over the northern Plains is forecast to move east
of the region on Day 3/Tuesday as a mid-level ridge builds inland
from the eastern Pacific, with the ridge axis remaining over the
Pacific Northwest through Day 4/Wednesday. Meanwhile, northwest flow
aloft is expected to persist across the northern Rockies and
northern High Plains, with surface pressure gradients weakening
behind the departing trough. The ridge is forecast to shift east by
Day 5/Thursday into the weekend, though guidance differs on the
timing of this progression. Low-level onshore flow should increase
west of the Cascades by Day 6/Friday and Day 7/Saturday, tightening
the surface pressure gradient across the Cascades as heat persists
over the interior.
...Day 3/Tuesday...
40% probabilities for Critical fire weather conditions have been
introduced across portions of southwest Wyoming, eastern Utah, and
western Colorado, where the most favorable overlap of wind/rh and
receptive fuels is expected. Locally critical fire weather
conditions are likely, as breezy surface winds overlap critical
minimum RH values from the Green River and Uintah Basins east across
western Colorado during the afternoon and early evening. Farther
northwest, elevated to locally critical fire weather conditions are
also possible across the Columbia River Gorge and adjacent
terrain-channeled areas, where easterly downslope flow is expected
to develop amidst critical RH values. However, sustained winds
appear likely to remain below critical thresholds.
...Day 4-5/Wednesday-Thursday...
Ridging and weakening surface pressure gradients should limit fire
weather concerns across much of the CONUS as temperatures rebound.
Nevertheless, minimum RH values are forecast to remain near critical
thresholds across portions of the interior Northwest, Great Basin,
and northern Rockies, with no appreciable wetting rainfall expected.
While periods of breezy winds remain possible where disturbances
move over the top of the ridge, coverage currently appears too
limited to introduce probabilities.
...Day 6-8/Friday-Sunday...
Critically dry fuels are expected to persist across the Great Basin,
northern Rockies, and northern High Plains through the end of the
forecast period, with the lowest minimum RH values and poorest
overnight recoveries across the Great Basin. The aforementioned
gradient should support stronger winds through the Cascade gaps and
across the Columbia Basin by Day 6/Friday and Day 7/Saturday, with a
similar increase suggested across the Snake River Plain and along
the northern Rocky Mountain Front. Though, at this time confidence
in coverage/duration of critical conditions is low. Nevertheless,
these areas will need to be monitored closely in future outlooks
given the lack of forecast precipitation through the extended
period.
..Elliott.. 08/02/2026
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