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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 231609
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1109 AM CDT Thu Apr 23 2026
Valid 231700Z - 241200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST AND
SOUTHERN AND CENTRAL PLAINS...
...Morning Update...
No changes were made to the previous forecast. Current satellite
imagery portrays mostly clear skies across the fire weather risk
areas. Very poor overnight humidity recoveries in the High Plains
have resulted in widespread 15-25 percent RH values as depicted in
morning surface observations. In eastern NM through the central TX
Panhandle, Critical conditions are already being observed with
sub-15 percent RH and sustained westerly winds over 20 mph (locally
sporadic gusts over 35 mph). As mid/upper level moisture shifts
southeast over the Continental Divide, cloud cover will gradually
increase this afternoon with chances for precipitation over the
central Plains, providing some relief to the fire environment.
However, portions of the southern Plains are expected to remain
under mostly clear skies through the evening. Minimal cloud cover
will yield better boundary layer mixing, allowing Critical
conditions to persist for up to 12 hours in some areas. A 700-850 mb
jet will strengthen from eastern NM into the TX Panhandle this
afternoon as the surface low deepens over northwestern OK,
increasing concerns for localized extremely critical conditions to
develop in terrain-influenced areas.
Across southern New England, a breezy post frontal environment will
develop in the wake of a passing dry cold front this afternoon. RH
is expected to drop to 25-35 percent with increasing northwesterly
winds of 10-15 mph at peak heating. However, marginal fuels and
recent precipitation precludes the introduction of fire weather
highlights.
See the previous discussion for more information.
..Elizalde-Garcia.. 04/23/2026
.PREV DISCUSSION... /ISSUED 1255 AM CDT Thu Apr 23 2026/
...Synopsis...
An upper-level trough and its accompanying mid-level jet streak will
move into the central CONUS today. Simultaneously, a surface trough
and cold front will advance through the central Plains and Upper
Midwest. The most acute fire weather risks are centered over the
central and southern High Plains, specifically behind and ahead of
the cold front. Within this corridor, intense southwesterly winds
will switch to the northwest following the frontal passage. When
coupled with low humidity and exceptionally dry fuels, these factors
will result in Elevated to Critical fire weather conditions.
...Southern and Central Plains...
Wind speeds just off the surface are expected to intensify from
eastern NM into the TX Panhandle by this afternoon, driven by
surface cyclogenesis over southern KS and northwest OK. Given that
the dryline is forecast to remain east of the Caprock through the
morning, moisture recovery will be lackluster across eastern NM and
the western TX Panhandle. With only minimal upper level clouds today
facilitating robust vertical mixing, expect RHs down to 10% or less,
while sustained westerly winds reach 20-25 mph.
The Critical area was expanded to include portions of northeast CO
and southwest NE. At least a few hours of critical conditions are
possible in northwest 15-20 mph winds behind the front before higher
RHs move over the area late in the day. Isolated pockets of
Extremely Critical conditions remain possible within the gap-flow
corridors of southeast CO and other terrain-influenced areas
stretching from eastern CO into the western TX Panhandle. In these
localized areas, sustained winds of 30 mph will likely overlap with
single-digit RHs.
To the north, an Elevated fire weather threat will persist across
the central Plains (including the remainder of eastern CO, western
KS, and much of NE) as dry, post-frontal northwesterly winds benefit
from downslope enhancement. This threat also encompasses portions of
the High Plains where the arrival of dry post-frontal air may cause
existing wildfires or dormant lightning holdovers from Wednesday to
flare up under the sustained dry and breezy regime. Precipitation
accumulation overnight will continue to be closely monitored over
portions of eastern South Dakota where elevated wind/RH conditions
are likely, but fuels are currently expected to become unreceptive.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 231909
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0209 PM CDT Thu Apr 23 2026
Valid 241200Z - 251200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF COLORADO FRONT RANGE
AND ADJACENT HIGH PLAINS...
...Afternoon Update...
Critical fire weather highlights have been introduced to portions of
the CO Rockies and adjacent High Plains where forecast guidance has
trended towards increased probabilities of very low RH and strong
winds. Beneath the upper trough, a surface low will emerge over
eastern CO promoting westerly downslope winds along the Front Range
and southwesterly winds over eastern CO. Deeper mixing will
encourage sustained winds of 15-25 mph and critically low RH of
10-15 percent (locally below 10 percent) at peak heating,
overlapping very dry fuels in a region where multiple preceding days
of critical fire weather conditions have further exacerbated the
fire environment. Elevated highlights have been expanded further
west to encompass the Four Corners into northwestern CO where
westerly winds of 15-20 mph and less than 20 percent RH will overlap
ERCs approaching the 75th-90th percentile.
..Elizalde-Garcia.. 04/23/2026
.PREV DISCUSSION... /ISSUED 1257 AM CDT Thu Apr 23 2026/
...Synopsis...
On Day 2/Friday, upper level ridging across the eastern U.S. will
begin to flatten, transitioning to a fairly zonal flow regime over
much of the southern CONUS. Meanwhile, a large-scale upper trough
will persist over the north-central U.S. along the Canadian border.
Expect very breezy and continued dry conditions through the end of
the work week over the Southwest and southern and central High
Plains.
...Southwest and Southern Plains...
The aforementioned westerly winds aloft will mix down to the surface
during peak heating, leading to strong westerly downslope flow
(sustained at 15-20 mph) and critically low RH (10-15%) that will
overlap very dry fuels on Day 2/Friday. Following several preceding
days of heightened fire weather conditions, the environment will be
further exacerbated across portions of the Southwest and southern
Plains. Winds look to be particularly strong near the Palmer Divide
in east-central CO; this area will be monitored for meeting Critical
thresholds if trends in forecast guidance continue. Increasing
clouds cover later in the day on Day 2/Friday is expected over much
of the region, which will likely work to mitigate some of the fire
weather threat before sunset.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 232110
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0410 PM CDT Thu Apr 23 2026
Valid 251200Z - 011200Z
...Synopsis...
A large scale upper trough will persist over the central U.S. and
Canada border through Day 4/Sunday. An upper ridge over the eastern
U.S. will break down as a mid-level shortwave approaches on Day
3/Saturday and widespread precipitation chances return, bringing
much needed relief to exceptionally dry fuels across the Piedmont
and Southeast. A secondary shortwave trough will move into the
Southwest on Day 4/Sunday with increasing southwest flow aloft,
inducing lee cyclogenesis over the central Plains. This pattern
change will bring widespread chances for precipitation across
portions of the High Plains into the Upper Midwest and Mid-South
through Day 6/Tuesday. However, in areas that do not see appreciable
rainfall, fire weather concerns are expected to linger. Towards the
end of the forecast period, an additional low-amplitude trough is
forecast to approach the southwestern U.S. Given the overall
pattern, fire weather conditions should persist where fuels remain
receptive.
...Day 3/Saturday and Day 4/Sunday - Southern Plains into portions
of the Southwest...
As upper troughing persists across the north-central U.S., strong
zonal flow over the Southwest will encourage very breezy and
continued dry conditions on Day 3/Saturday. With preceding days of
Critical fire weather conditions, westerly downslope flow of 15-20
mph and 10-15 percent RH atop dry fuels will further exacerbate the
fire environment, supportive of 40% Critical probabilities on Day
3/Saturday. A strong mid-level disturbance is forecast to cross over
the High Plains on Day 4/Sunday, resulting in lee cyclogenesis over
portions of eastern CO and western KS. Behind an emerging dryline,
westerly downslope flow is expected to promote very strong winds and
critically low RH overlapping a dry fuelscape. Both 40% and 70%
Critical probabilities have been maintained to encompass the
expansive fire weather threat.
As the upper trough shifts east across the Midwest, a dry airmass
will persist over the Southwest and southern Plains early next week.
Breezy conditions may emerge in advance of an approaching upper
trough later in the forecast period, albeit model guidance varies in
the timing and strength of the overall upper pattern. Thus, guidance
ambiguity precludes the introduction of probabilities at this time.
..Elizalde-Garcia.. 04/23/2026
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