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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 171650
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1150 AM CDT Tue Mar 17 2026
Valid 171700Z - 181200Z
...CRITICAL FIRE WEATHER AREA FOR NORTH-CENTRAL TEXAS INTO SOUTHWEST
OKLAHOMA...
The Critical area over the southern Plains was expanded to include a
slightly larger portion of central Texas and into nearby areas of
southwestern Oklahoma. Forecast guidance is indicating that this
region will experience at least a few hours of slightly stronger
westerly winds, sustained at 15-25 mph with minimum RHs near 10-20%.
Surface observations over this area are already indicating a
tightening pressure gradient with sustained southwest winds up to
15-20 mph and RHs dropping into the mid-teens. Over central Wyoming,
the latest forecast guidance shows that much of central portions of
the state are not expected to reach elevated criteria with RH
struggling to fall below 30%. Thus, portions of the Elevated area
were trimmed toward the south commensurate with the spatial extent
of the lowest RHs in this area. All other areas remain on track.
..Stearns/Williams.. 03/17/2026
.PREV DISCUSSION... /ISSUED 0122 AM CDT Tue Mar 17 2026/
...Synopsis...
Elevated to critical fire weather conditions are expected today
across the High Plains and southern Plains. Very dry conditions are
prevalent across the central CONUS in the wake of a strong frontal
passage (dewpoints in the single digits to low teens over the Plains
are near/below the 10th percentile for mid-March). Surface high
pressure over the southern CONUS will continue to shift east through
the day as a lee trough deepens along the High Plains. The resulting
pressure gradient winds across the southern Plains and off downslope
flow the western slopes of the Rockies will promote elevated to
critical fire weather conditions over regions with recent wildfire
activity.
...Southern Plains...
Forecast guidance continues to show strengthening southwest winds
through the afternoon across central TX to central OK as the
pressure gradient strengthens with the deepening surface trough
along the High Plains. Relative humidity reductions will be most
pronounced (and possibly as low as 10-15%) from western TX into
southwest OK under the low-level thermal ridge. Model consensus
suggests winds through this corridor will increase to 15-20 mph;
however, guidance typically under-mixes the boundary layer in dry
return flow regimes with higher RH values and weaker winds than
actually observed. Based on this, the expectation is that winds
under the thermal ridge will likely be sustained near 20 mph, which
will increase the probability of sustained critical fire weather
conditions. A targeted critical risk area has been introduced across
this region.
...Central to southern High Plains...
Westerly 15-20 mph winds off the central to southern Rockies will
support several areas of elevated fire weather conditions from
central and southeast WY southward into West TX. Forecast guidance
show reasonably good agreement in RH reductions down to 20% with
areas of 15% possible. Solutions that typically over-mix in these
regimes (notably the RAP and HRRR) hint that 20-25 mph winds are
possible across southeast WY into far northeast CO and parts of the
NE Panhandle where active wildfires have been ongoing in recent
days. Confidence in sustained critical conditions across this
corridor is limited due to spread in guidance and poor ensemble
agreement, but given the very dry conditions, observed trends will
be monitored for the need for Critical highlights.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 171913
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0213 PM CDT Tue Mar 17 2026
Valid 181200Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEAST
WYOMING...EXTREME WESTERN NEBRASKA...AND EXTREME NORTHERN
COLORADO...
A Critical area has been introduced over portions of southeast
Wyoming, extreme western Nebraska, and extreme northern Colorado. In
this area, forecast guidance indicates sustained west-northwest
winds of 20-25 mph combined with RHs of 10-18% by mid-afternoon. The
strongest winds will be near and east of the leeward slopes of the
Laramie Mountains. In this area, the duration of critical wind/RH
will likely approach 5 or more hours during peak heating.
The Elevated area was expanded to the east and south across the
northern and central Colorado plains and farther into the
southwestern South Dakota and the Nebraska Panhandle. The limiting
factors for expansion farther west and north are cloud cover and
existing marginal fuel receptiveness. However, given the persistent
pattern and resultant anomalous temperatures expected over much of
the region, this area will be watched closely for potential
expansion as fuels continue to dry.
..Stearns/Williams.. 03/17/2026
.PREV DISCUSSION... /ISSUED 0144 AM CDT Tue Mar 17 2026/
...Synopsis...
Elevated fire weather conditions will persist across portions of the
central High Plains on Wednesday. An anomalously strong upper ridge
will gradually build across the Southwest over the next 48 hours,
which will establish a northwesterly flow regime over the central
CONUS. With stronger mid-level flow displaced towards the northern
Rockies, lee troughing will become most pronounced across central MT
to eastern WY Wednesday morning through the afternoon. Confidence is
fairly high (80%) in sustained winds between 15-25 mph across
central WY into the NE Panhandle and far northeast CO. A resumption
of westerly downslope flow will support RH reductions into the
20-25% range based on ensemble consensus. Drier/more well-mixed
solutions hint at RH reductions as low as the 10-15% range, which
would support a swath of critical fire weather conditions (mainly
across central to southeast WY). However, confidence in this
potential is limited based on modest ensemble probabilities (around
40-50% probability of RH reductions below 15%). Regardless,
antecedent drought conditions and preceding dry/windy conditions on
Tuesday will maintain dry fuels (and/or help cure fine fuels in
areas that recently received precipitation) to support the fire
weather threat Wednesday afternoon.
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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