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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 191639
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1139 AM CDT Thu Mar 19 2026
Valid 191700Z - 201200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL AND EASTERN WYOMING...
The Elevated area over the northern High Plains was expanded
slightly northward into eastern portions of Montana, North Dakota,
and South Dakota. This subtle expansion is commensurate with the
latest extent of forecast guidance wind/RH reflecting more robust,
through time and space, boundary layer mixing across this area. As
was previously mentioned, eastern portions of the Snake River Valley
in Idaho are expected to reach elevated wind/RH thresholds this
afternoon. After reviewing additional fuels guidance across the area
in light of the hot and dry conditions, the Elevated area was
expanded to include this area as well.
All other areas remain on track with poor overnight RH recoveries
across much of Intermountain West going into today. This will extend
burn periods across much of the southern two-thirds of the western
US as this early season heat wave continues. Additional details can
be found in the previous forecast discussion.
..Stearns/Williams.. 03/19/2026
.PREV DISCUSSION... /ISSUED 0125 AM CDT Thu Mar 19 2026/
...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.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 191836
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0136 PM CDT Thu Mar 19 2026
Valid 201200Z - 211200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL AND EASTERN WYOMING...
No changes were made to the drawn areas. The expected conditions
remain on track with the latest forecast guidance. Across portions
of central/northern Nevada and extreme southeast Oregon, expect to
see localized sustained winds of 10-15 mph and RHs down to 10-15%
during peak heating on Day 2/Friday. Given the marginal early season
fuel conditions and sporadic coverage of coincident winds and RH,
fire weather highlights were not introduced with this issuance.
However, trends over the western Great Basin and nearby areas will
be watched with future forecasts.
..Stearns/Williams.. 03/19/2026
.PREV DISCUSSION... /ISSUED 0204 AM CDT Thu Mar 19 2026/
...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.
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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