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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 190625
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0125 AM CDT Thu Mar 19 2026
Valid 191200Z - 201200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL AND EASTERN WYOMING...
...Synopsis...
Upper-level riding will persist across the Southwest with strong
northwesterly upper-level flow remaining in place across the
northern Rockies and central CONUS. This will support a continued
downslope regime across the central/northern 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. Elsewhere, strong surface winds and reduced RH are expected
to yield elevated fire weather conditions across portions of
central/southern Oregon.
...Central/Northern High Plains...
Anomalously strong upper-level ridging will persist across the
Southwest today with strong upper-level northwesterly flow in place
across the central/northern Rockies. At the surface, high pressure
across the Intermountain West will combine with a low pressure
system shifting southeastward across the Canadian Prairies to
support west-northwesterly downslope winds of 20-25 mph and reduced
RH values of 10-15% across portions of central and eastern Wyoming.
With persistent dry/windy conditions continuing to aid in the
maintenance of receptive fuels, these conditions are expected to
support critical fire weather conditions this afternoon. While the
strongest low-to-mid level flow is forecast to be displaced farther
north, deep boundary layer mixing may still support occasional wind
gusts to 30-35 mph across this area.
Elevated fire weather concerns are also expected across adjacent
regions, including much of the Wyoming Basin eastward into portions
of northern Colorado, southwestern South Dakota, and northeastern
Nebraska where sustained westerly surface winds of 15-20 mph and
reduced RH of 10-15% are forecast amid the downslope wind regime.
Elevated highlights have also been expanded farther north and east
into much of southern Montana given similar forecast meteorological
conditions and recent wildfire activity noted in the region.
...Oregon...
Just west of the upper-level ridge axis, a strengthening surface
pressure gradient is forecast to yield west-southwesterly sustained
surface winds of 10-20 mph with RH values falling to 10-20% this
afternoon across portions of central and southeastern Oregon with
temperatures forecast well above normal. This combination of hot,
dry, and windy conditions is expected to support elevated fire
weather concerns prior to green up.
...Eastern Idaho...
Latest high-res guidance depicts sustained westerly to southwesterly
surface winds of 10-20 mph developing within the Snake River Valley
through today amid a tightening surface pressure gradient. While RH
values are forecast to drop to 15-25%, marginal fuel receptiveness
is expected to preclude widespread fire weather concerns.
..Chalmers.. 03/19/2026
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 190704
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0204 AM CDT Thu Mar 19 2026
Valid 201200Z - 211200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN
WYOMING...
...Synopsis...
A persistent upper-level ridge will remain centered over the
Southwest on D2/Friday, with modest northwest flow aloft persisting
across the central/northern High Plains. Surface high pressure over
the Intermountain West coupled with lee troughing across the
northern Plains will support a continued downslope wind regime, with
dry/windy conditions forecast to yield elevated to critical fire
weather concerns across portions of the central and northern High
Plains.
...Central/Northern High Plains...
Anomalously strong upper-level ridging across the Southwest will
continue to support the potential for record warm temperatures
across much of the West. With high pressure remaining positioned
across the Intermountain West and lee troughing in place across the
northern Great Plains, a persistent downslope wind regime is
forecast to yield sustained west-northwesterly surface winds of
15-25 mph across much of the central/northern High Plains. Coupled
with reduced RH values of 10-15% and receptive fuels, this will
support critical fire weather conditions across portions of
central/eastern Wyoming. Elevated fire weather concerns are forecast
across adjacent areas of the western Wyoming Basin and portions of
southwestern South Dakota and western Nebraska where lighter surface
winds of 15-20 mph are forecast to overlap reduced minimum RH values
of 10-15%. Farther north across much of southern Montana, RH values
are expected to remain more marginal (15-25%); however, ongoing fire
activity and sustained westerly surface winds of 15-25 mph warrant
the addition of Elevated fire weather highlights.
...Oregon...
Some guidance indicates westerly surface winds will strengthen amid
a tightening surface pressure gradient ahead of an approaching cold
front through D2/Friday. Continued dry/windy conditions may support
localized elevated fire weather concerns, but remaining uncertainty
regarding the strength and duration of stronger winds as well as how
low RH will fall in the afternoon precludes the inclusion of
Elevated fire weather highlights at this time. Conditions will
continue to be monitored for future updates.
..Chalmers.. 03/19/2026
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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