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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 171618
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1118 AM CDT Thu Sep 17 2026
Valid 171700Z - 181200Z
No changes were made to the Elevated risk areas across the Great
Basin and Southern Plains. Please see previous forecast discussion
for more details.
...Central Idaho and Northeastern Oregon...
Scattered showers and thunderstorms associated with an upper low
over northern CA and accompanying mid-level jet arc across portions
of south-central OR into central mountains of ID and northern UT.
Additional thunderstorms (some potentially severe across central ID)
are expected this afternoon as MLCAPE rises to as high as 1000 J/kg
under diffluent flow aloft within the jet exit region. Although more
cloud-to-ground lightning and a few ignitions are expected today,
additional showers/thunderstorms, cooler temperatures and higher
relative humidity are forecast D2/Friday and D3/Saturday as the low
shifts eastward. This should limit overall holdover ignition
concerns amid marginal fuels.
..Williams.. 09/17/2026
.PREV DISCUSSION... /ISSUED 1248 AM CDT Thu Sep 17 2026/
...Synopsis...
Expanding high pressure over the Southeast and central U.S will
contribute to widespread above normal temperatures and dry
conditions today. Meanwhile, an upper-level low will remain centered
over northern California/southern Oregon, sustaining strong
southwesterly flow over the Great Basin.
...Southern Plains...
Strong surface heating and deep vertical mixing will contribute to
15-25% RH values and sustained southerly winds of 10-15 mph this
afternoon. These meteorological conditions will overlap an
exceptionally dry and receptive fuelscape in southwestern Oklahoma
and along the Red River Valley, supporting the introduction of
Elevated highlights.
...Great Basin...
South-southwesterly sustained surface winds of around 15 mph are
expected to evolve under an expanding 50 kt mid-level jet this
afternoon. A dry and well mixed boundary layer will promote RH
values of around 15% across central/northern NV and southern ID.
Consecutive days of dry and windy conditions have led to
increasingly more receptive fuels across the region, maintaining an
Elevated fire weather risk.
...Central Idaho and Northeastern Oregon...
Isolated to scattered showers and thunderstorms are expected across
northern California, Oregon, and the Northern Rockies as the
upper-level low begins to pivot northeastward out of northern CA.
The primary driver of limited rainfall will be fast
north-northeastward storm motions of 30-40 mph, particularly on the
nose of the mid-level jet across the central ID mountains; however,
marginal fuels, and subsequent showers/thunderstorms on Day 2/Friday
and Day 3/Saturday as the low transitions into the Northern Rockies
should reduce holdover ignition concerns.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 171927
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0227 PM CDT Thu Sep 17 2026
Valid 181200Z - 191200Z
...Southern Plains...
A surface trough across the central Plains will promote southerly
winds of 10-15 mph over southern KS, western OK and the TX Panhandle
D2/Friday. These winds atop very dry fuels particularly across
southwestern OK, afternoon RH reductions to around 25% and
temperatures near 100F will support elevated fire weather concerns
across southwestern OK and the adjacent Red River Valley. The far
eastern extent of highlights were removed across south-central OK
with ensemble guidance showing 10% or less probabilities of wind
speeds at or above 15 mph.
..Williams.. 09/17/2026
.PREV DISCUSSION... /ISSUED 1250 AM CDT Thu Sep 17 2026/
...Synopsis...
As an upper low slowly meanders into the Northern Rockies on Day
2/Friday, high pressure in the Southeast will retrograde westward
and center over the ArkLaTex region. As a result, above normal
temperatures will continue for much of the southern Plains and Deep
South where rainfall neglected fuels have become increasingly
receptive.
...Southern Plains...
A surface trough ahead of an advancing cold front across the central
Plains will promote slightly higher south-southwest winds to
portions of the southern Plains on Day 2/Friday. While guidance
depicts RH values to be at or above 25-30%, observed values will
likely be much lower as a result of an increasing vapor pressure
deficit (90th percentile or greater for the last 15-30 days) amid an
exhibited decrease in evapotranspiration due to long term drought
and stressed fuels. Sustained wind speeds of 10-15 mph are expected
atop very dry and recently receptive fuels, necessitating an
introduction of Elevated highlights across southwestern Oklahoma and
northern Texas.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 172126
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0426 PM CDT Thu Sep 17 2026
Valid 191200Z - 251200Z
...Synopsis...
A weakening upper-level trough will push into the central Plains by
D4/Sunday with associated precipitation expected across the Northern
Rockies and northern Plains through the weekend. Dry southerly flow
in advance cold front will sustain a fire weather threat over
portions of the Southern Plains D3/Saturday. The cold front and
related precipitation will bring some temporary relief to the
Southern Plains beginning D4/Sunday. Hot and mostly dry conditions
under an upper ridge are likely through the middle of next week
across the lower MS River Valley but prevailing light winds should
keep overall fire weather concerns suppressed. Stronger southwest
winds could return to portions of the Pacific Northwest and Great
Basin late next week as a potential upper trough evolves but an
expected marginal fuelscape should limit the fire weather threat for
the region.
...Day 3/Saturday...
A tightening pressure gradient ahead of an approaching cold front
should support south-southwest winds of 10-15 mph by Saturday
afternoon over portions of the Southern Plains. The winds coupled
with lower daytime RH and receptive fuels (ERCs in the 90-95th
percentile range) will promote a fire weather threat for portions of
southwestern OK and northwestern TX. Model guidance shows a corridor
of lower surface dewpoints across eastern OK where RH could fall to
or below 20% Saturday afternoon as temperatures climb to near 100F.
Thus, extended 40% critical probabilities into portions of eastern
OK to cover this drier air mass. Conditions will improve overall
across the Southern Plains beginning D4/Sunday as the cold front
progresses southward bringing much needed rain to some locations and
cooler temperatures to the region.
..Williams.. 09/17/2026
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