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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 181931
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0231 PM CDT Wed Mar 18 2026
Valid 191200Z - 201200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN
WYOMING...
...Oregon...
An Elevated area was introduced over portions of central and eastern
Oregon on Day 2/Thursday. Just west of the large ridge axis,
forecast guidance is indicating sustained southwest surface winds of
10-20 mph with RHs falling to 10-20% during peak heating.
Additionally, temperatures are expected to rise 15-25 degrees above
normal, approaching daily records. While fire concerns are not
normally a concern for this time of year across this area, this hot,
dry, and windy combination warrants highlighting ahead of green up.
...Central/Northern High Plains...
The Elevated area over much of Wyoming was expanded to include
extreme southeastern Montana, portions of southwest South Dakota,
and more of western Nebraska. While forecast certainty in the areal
expansion of elevated wind/RH conditions has increased with the
latest model guidance, fuels guidance has also indicated very dry
vegetation in place over the region adjacent to the earlier Elevated
area. The existing Critical area remains on track as previously
described.
..Stearns/Williams.. 03/18/2026
.PREV DISCUSSION... /ISSUED 0204 AM CDT Wed Mar 18 2026/
...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.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 182147
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0447 PM CDT Wed Mar 18 2026
Valid 201200Z - 261200Z
A persistent upper-level ridge centered over the California/Arizona
border will dominate the weather across the western US through Day
3/Friday. A shortwave trough will crest the ridge, moving through
the Pacific Northwest on Day 4/Saturday before crossing the northern
Plains and Great Lakes region Day 5/Sunday into Day 6/Monday. The
latest forecast guidance continues to break down the upper-level
ridge, at least temporarily, shifting the corridor of stronger
mid-level flow further south late in the period. This will also
coincide with a cold front pushing south through the Plains on Day
5/Sunday. A ridge begins to build over the western US again starting
on Day 7/Tuesday.
On Day 3/Friday through Day 4/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
and windy conditions across much of Wyoming, far northern Colorado,
southern Montana, portions of western South Dakota, and Nebraska. A
70% area was introduced for Day 3/Friday, reflecting high confidence
in sustained westerly winds of 20-30 mph overlapping with RH values
of 12-20% during peak heating across portions of eastern Wyoming.
On Day 4/Saturday and Day 5/Sunday, current guidance suggests the
potential for critical conditions over portions of the central and
southern High Plains and a good portion of the Southwest as the
aforementioned cold front passes through. As such, there was a
significant increase in coverage for the 40% area versus the last
issuance. The factor precluding additional expansion into the Great
Basin is currently sub-critical fuel conditions over that region.
The 40% area was also slightly expanded for Day 5/Sunday to account
for strengthening southwesterly flow across portions of Texas and
southwest Oklahoma. Some areas across the southern Plains may see
the burn period extended through much of the Day 4/Saturday night
period due to a well-mixed nocturnal environment.
As the ridge begins to build back over the western US on Day
7/Tuesday, fire weather conditions appear to remain subdued. By Day
8/Wednesday, the latest forecast guidance is hinting at yet another
period of hot, dry, and windy conditions focused over much of
Wyoming and surrounding areas yet again. No areas were included with
this issuance, but they may be needed over this area if forecast
certainty continues to increase during this time period.
Record temperatures and dry conditions will continue to desiccate
fuels over several consecutive days across the southern two-thirds
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.. 03/18/2026
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