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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 181530
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1030 AM CDT Wed Mar 18 2026
Valid 181700Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN
WYOMING...EXTREME WESTERN NEBRASKA...AND EXTREME NORTHERN
COLORADO...
...Central High Plains...
Strong winds are already evident from surface observations this
morning across the higher elevations of southern Wyoming. As was
previously mentioned, a deep boundary layer associated with much
above normal temperatures will mix winds toward the surface this
afternoon. Thus, the forecast remains on track today with no changes
to the drawn areas.
...Southeast...
Worth noting are the breezy, post-frontal northerly winds over
northern Florida and southern Georgia this afternoon. This offshore
flow will support drying over the region. However, recent rainfall
combined with marginal locally elevated wind/RH conditions are
expected to keep the overall fire environment subdued.
..Stearns/Williams.. 03/18/2026
.PREV DISCUSSION... /ISSUED 0116 AM CDT Wed Mar 18 2026/
...Synopsis...
A northwesterly upper-level flow regime will become established over
the northern Rockies and central CONUS today downstream of an
anomalously strong upper-level ridge centered over the Southwest.
This setup will favor strong downslope flow in the lee of the
central Rockies, with westerly to northwesterly surface winds and
very low RH values supporting elevated to critical fire weather
conditions across portions of the central High Plains.
...Portions of the central High Plains...
Northwesterly upper-level flow will strengthen across the northern
Rockies and central CONUS today downstream of an anomalously strong
upper-level ridge centered over the Southwest. With stronger
mid-level flow displaced toward the northern Rockies, surface lee
troughing will become most pronounced across central Montana to
eastern Wyoming this morning into this afternoon. When coupled with
surface high pressure established across the Intermountain West,
this will support strong downslope flow in the lee of the central
Rockies, with forecast guidance indicating sustained westerly to
northwesterly surface winds of 20-25 mph overlapping very low RH of
10-15%. With antecedent drought conditions and preceding dry/windy
conditions maintaining dry fuels and helping cure fine fuels in
areas that recently received precipitation, this will support
critical fire weather conditions across portions of southeastern
Wyoming, the western Nebraska Panhandle, and extreme northern
Colorado. The strongest winds are forecast near and east of the
leeward slopes of the Laramie Range, where deep boundary layer
mixing coupled with strong mid-level flow will also support the
potential for wind gusts of 30-35 mph. Latest high resolution
guidance also indicates slightly enhanced potential for critical
conditions within the North Platte River Valley from eastern Wyoming
into western Nebraska where topographical influences may locally
enhance downsloping effects.
Elsewhere across the central High Plains, westerly to northwesterly
downslope winds of 15-25 mph will overlap reduced RH values of
15-25% to support elevated fire weather conditions across much of
eastern Wyoming, extreme southwestern South Dakota, the Nebraska
Panhandle, northeastern Colorado, and extreme northwestern Kansas.
Marginal fuel receptiveness is expected to limit widespread elevated
fire weather concerns for areas farther north and west at this time.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 180704
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0204 AM CDT Wed Mar 18 2026
Valid 191200Z - 201200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN WYOMING...
...Synopsis...
Upper-level ridging will remain in place across the Southwest for
D2/Thursday, with strong northwesterly upper-level flow persisting
across the northern Rockies and central CONUS. This will support a
continued downslope regime across the central High Plains and
western Wyoming Basin, with elevated to critical fire weather
conditions expected amid strong west-northwest surface winds and
very low RH values.
...Portions of the central High Plains into the western Wyoming
Basin...
The synoptic-scale pattern will remain relatively consistent from
today into D2/Thursday, with anomalously strong upper-level ridging
persisting across the Southwest and strong northwesterly flow in
place across the central Rockies. At the surface, high pressure
across the Intermountain West will couple with surface low pressure
shifting southeastward across southern Canada to support reduced RH
values of 10-15% and west-northwesterly downslope winds of 20-25
mph. With persistent dry/windy conditions continuing to aid in the
maintenance of receptive fuels, this is expected to yield critical
fire weather conditions across much of southeastern Wyoming. Current
guidance indicates mid-level flow will weaken slightly from D1 into
D2, but deep boundary layer mixing may also support wind gusts of
30-35 mph across much of this area.
Elevated fire weather concerns are also expected across adjacent
regions, including much of southwestern Wyoming, portions of extreme
northern Colorado, the western Nebraska Panhandle, extreme
southwestern South Dakota, and extreme northeastern Utah, where
sustained westerly surface winds of 15-20 mph are forecast to
overlap reduced RH of 10-15%. Marginal fuel receptiveness and lower
confidence in higher sustained winds are expected to limit the
northern extent of widespread elevated fire weather concerns at this
time; however, this area will be monitored for potential expansion
as fuels continue to dry given the persistent pattern and resultant
anomalous temperatures expected over much of the region.
..Chalmers.. 03/18/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 172128
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0428 PM CDT Tue Mar 17 2026
Valid 191200Z - 251200Z
The synoptic pattern will remain fairly consistent throughout much
of the forecast period, dominated by a persistent upper-level ridge
centered over the California/Arizona border. A shortwave trough will
crest the ridge, moving through the Pacific Northwest on Day
5/Saturday before crossing the northern Plains and Great Lakes
region Day 6/Sunday into Day 7/Monday. Recent forecast guidance
suggests this passing shortwave may dampen the amplitude of the
upper-level ridge more than previously indicated, potentially
shifting the corridor of stronger mid-level flow further south late
in the period.
On Day 3/Thursday through Day 5/Saturday, moderate northwest flow
aloft will remain in place over much of the central High Plains.
Record warm temperatures are likely as the ridge builds across the
western US, leading to deep boundary-layer mixing and resultant dry,
windy conditions across portions of southeast Wyoming, the northern
Colorado plains, and western Nebraska. A 70% area was introduced for
Day 3/Thursday, reflecting high confidence in sustained westerly
winds of 20-30 mph overlapping with RH values of 10-15% during peak
heating. While the signal for critical winds is lower on Day
4/Friday or Day 5/Saturday, these areas will be monitored for future
changes.
On Day 5/Saturday and Day 6/Sunday, current guidance suggests the
potential for critical conditions over portions of the southern and
central Plains. Given the consistency in model solutions favoring
the southern Plains, a 40% area was added over the Texas and
Oklahoma Panhandles and adjacent states for Day 5/Saturday. This
area will likely require spatial expansion in subsequent updates as
confidence in the wind field extent increases. Another 40% area was
added for Day 6/Sunday to account for strengthening pre-frontal
southwesterly flow across portions of Texas.
Record temperatures and dry conditions will continue to desiccate
fuels over several consecutive days across the southern half of the
western US through the outlook period. Independent of wind speeds,
high vapor pressure deficits and low RH values suggest extended burn
periods across these areas where fuels become increasingly receptive
to ignition.
..Stearns/Williams.. 03/17/2026
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