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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 201546
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1046 AM CDT Fri Mar 20 2026
Valid 201700Z - 211200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN WYOMING...
Visible satellite data depicts clear skies, with boundary-layer
warming underway. Surface observations show temperatures reaching
the 60s F in spots, with RH dipping to 20 percent, and westerly
surface winds approaching 20 mph amid 25 mph gusts. Guidance
consensus suggests that boundary-layer mixing will continue into the
afternoon hours, resulting in overlapping widespread 15-20 percent
RH and 15-20 mph sustained westerly surface winds. As such, the
current Elevated and Critical highlights across the northern High
Plains into the northern Rockies have been maintained.
..Squitieri.. 03/20/2026
.PREV DISCUSSION... /ISSUED 0115 AM CDT Fri Mar 20 2026/
...Synopsis...
A persistent upper-level ridge will remain centered over the
Southwest today with modest northwest flow aloft across the
central/northern High Plains. Surface high pressure over the
Intermountain West coupled with lee troughing across the northern
Great Plains will continue to favor a downslope wind regime, with
dry and windy conditions forecast to support elevated to critical
fire weather concerns across portions of the central and northern
High Plains.
...Central/Northern High Plains...
Record warm temperatures continue across much of the West amid an
anomalously strong upper-level ridge centered across the Southwest.
With high pressure remaining in place across the Intermountain West
and lee troughing across the northern Great Plains, a continuing
downslope wind regime is forecast to yield sustained
west-northwesterly surface winds of 20-25 mph across portions of
central/eastern Wyoming. Poor overnight RH recoveries have been
noted via recent surface observations with further RH reductions to
10-20% forecast this afternoon. Coupled with receptive fuels, this
is expected to support critical fire weather conditions across
central/eastern Wyoming today. Elevated fire weather concerns are
also forecast across adjacent areas of the western Wyoming Basin and
portions of southwestern South Dakota and western Nebraska where
surface winds of 15-20 mph are expected to overlap minimum RH values
of 10-20%.
Fuels remain more marginal farther to the north across much of
southern Montana and portions of extreme southwestern North Dakota
and northwestern South Dakota; however, continued warm/dry
conditions have supported some drying of fine fuels along with
recent fire activity. Given this, elevated fire weather conditions
are expected this afternoon as RH values are forecast to range from
15-25% amid stronger sustained westerly winds of 15-25 mph. 40+
knots of 700 mb flow across this region coupled with deep boundary
layer mixing may also support occasional wind gusts of 30-40 mph.
...Central Nevada into southern Oregon...
Guidance continues to indicate localized potential for sustained
southwesterly surface winds of 10-15 mph this afternoon as the
surface pressure gradient tightens ahead of an approaching cold
front. With RH values forecast to fall to 10-15%, localized elevated
fire weather concerns may materialize across portions of southern
Oregon into central Nevada, especially in areas that favor
terrain-induced wind enhancements. However, widespread elevated
conditions are not expected at this time given marginal early season
fuel conditions and sporadic coverage of coincident elevated wind/RH
criteria.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 200729
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0229 AM CDT Fri Mar 20 2026
Valid 211200Z - 221200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHERN/CENTRAL HIGH
PLAINS AND WESTERN WYOMING BASIN...
...Synopsis...
A cold front will surge south through the northern/central Great
Plains and northern Great Basin with a surface low developing
southward in the lee of the Rockies. A widespread strengthening of
surface winds ahead of this frontal system coupled with reduced RH
values is forecast to support elevated to critical fire weather
concerns from the southern/eastern Great Basin through the central
Great Plains.
...Southern/eastern Great Basin to the central Great Plains...
Forecast guidance continues to depict at least a temporary break
down of the upper-level ridge centered over the Southwest on
D2/Saturday as a shortwave trough crests the ridge and moves through
the Pacific Northwest. Simultaneously, a surface low will develop
southward in the lee of the Rockies while an associated cold front
advances southward across much of the West and the Great Plains. The
strongest sustained winds (20-30 mph) coupled with minimum RH values
of 10-15% are forecast to support critical fire weather conditions
across southeastern Wyoming and adjacent portions of western
Nebraska, northwestern Colorado, extreme northeastern Utah, and
extreme southwestern South Dakota. Modest westerly mid-level flow
coupled with deep boundary layer mixing will also support the
potential for occasional wind gusts of 30-35 mph across this area.
Elsewhere within the Elevated highlights, a strengthening surface
pressure gradient ahead of this frontal system will support
widespread sustained surface winds of 10-20 mph. With continuing
potential for record warm temperatures across much of the West
aiding in the drying of fine fuels and forecast RH values of 10-20%
(locally down to 5%) during peak heating, widespread elevated fire
weather conditions are expected from the southern/eastern Great
Basin eastward to the central Great Plains and from portions of West
Texas northward to Wyoming. While much of the high elevations of the
central Rockies are within the Elevated area, fuel conditions and
snow cover will preclude any fire weather concerns in those areas.
The southward moving cold front will then bring a shift to northerly
winds for the central/northern High Plains and northern Great Basin.
This front is anticipated to be dry, however, which may bring the
potential for elevated fire weather conditions to temporarily
persist after the frontal passage.
..Chalmers.. 03/20/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 192128
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0428 PM CDT Thu Mar 19 2026
Valid 211200Z - 271200Z
A shortwave trough will crest the existing well-established
Intermountain West ridge, moving through the Pacific Northwest on
Day 3/Saturday before crossing the northern Plains and Great Lakes
region Day 4/Sunday into Day 5/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.
Meanwhile, at the surface, a cold front will surge south through the
northern and central Plains on Day 3/Saturday and Day 4/Sunday.
While uncertainty remains in the timing of this front, forecast
guidance suggests that it will be dry. This would present concerns
both ahead of and behind the front as it passes. On Day 5/Monday and
Day 6/Tuesday, the ridge will again build over the Intermountain
West with a potential breakdown on Day 7/Wednesday or Day 8/Thursday
with the passing of another upper-level shortwave trough across the
northern CONUS.
On Day 3/Saturday, moderate westerly flow aloft will remain in place
over much of the central High Plains. Record warm temperatures are
likely for yet another day as the ridge builds across the western
US. A 70% area was introduced for Day 3/Saturday, reflecting high
confidence in sustained westerly winds of 20-30 mph overlapping with
RH values of 10-20% during peak heating. Additionally, the 40% area
was significantly expanded to include the southeastern half of the
Great Basin, the northern half of the Southwest, and portions of the
central and southern High Plains. While much of the high elevations
of the central Rockies are within the drawn area, fuel conditions
and snow cover will preclude any fire weather concerns in those
areas.
On Day 4/Sunday, the 40% area was again significantly expanded to
account for strengthening southwesterly flow across large portions
of New Mexico, Texas, and Oklahoma. However, the northern extent of
this area will likely be adjusted to account for the timing of the
frontal boundary. While this cold front will be impactful in
bringing stronger winds to the central portions of the CONUS,
temperatures behind the front will barely fall back to seasonal
averages.
On Day 5/Monday, deep surface mixing under westerly flow will again
impact southern Wyoming resulting in another day of 10-20 mph winds
and RHs down to 15-20%. Over the lee side of the central
Appalachians, expect post-frontal northwesterly winds of 10-15 mph
to combine with RHs of 20-30% resulting in an additional 40% area.
As the ridge begins to build back over the western US on Day
6/Tuesday, fire weather conditions appear to remain subdued. By Day
7/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. A 40% area was included for this
region as deep boundary layer mixing will again introduce a corridor
of strong westerly winds of 15-25 mph coinciding with RHs of 10-20%.
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. One piece of good news is that
far northern portions of the CONUS, including areas highlighted in
the Day 1/Thursday through Day 2/Friday time frame may receive at
least minimal mounts of precipitation as each of the aforementioned
troughs move across the International Border with Canada.
..Stearns/Williams.. 03/19/2026
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