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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 200628
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0128 AM CDT Mon Apr 20 2026
Valid 201200Z - 211200Z
...Synopsis...
Upper-level ridging will gradually shift eastward from the Rockies
into the Plains through today as an upper-level trough departs the
East Coast and a second, closed upper trough approaches the West
Coast. Surface high pressure will shift east over the
Southeast/Mid-Atlantic while a lee trough deepens along the
central/northern High Plains.
...Portions of the central High Plains...
A deepening lee trough along the central High Plains will support
strengthening westerly downslope winds to the west of the trough
axis across portions of southeastern Wyoming into southwest South
Dakota and much of western/central Nebraska. Farther south/east,
high pressure over the Lower Mississippi Valley in conjunction with
the lee trough will yield a tightened surface pressure gradient and
strengthening southerly winds from the TX/OK Panhandle vicinity
northeastward into central Kansas and south-central Nebraska.
Sustained winds of 15-20 mph are expected within both of these
regimes. RH minimums of 10-15% (locally lower) are expected across
southeast Wyoming, southwest South Dakota, and western Nebraska
where downslope wind will depress moisture content within an
antecedent dry air mass. Farther south/east, the northern fringe of
returning moisture may limit RH reductions to some degree, but RH
minimums are still forecast to fall to 15-25% southeastern Colorado
northeastward into south-central Nebraska. With dry, receptive fuels
across much of the region, this will support widespread elevated
fire weather conditions for a few hours this afternoon. Locally
critical conditions will also be possible in the lee of the Laramie
Mountains in southeastern Wyoming where winds may occasionally gust
to 30-35 mph.
...Portions of the Southeast...
A dry air mass will continue to reside across much of the Southeast
where fuels remain exceptionally dry (ERCs above the 95th
percentile) amid continuing drought. Sustained northeasterly winds
of 10-15 mph along the southern periphery of surface high pressure
are forecast to overlap minimum RH values of 15-25% across much of
the Florida Panhandle and adjacent areas of southern
Alabama/Georgia. Farther north, modest westerly/northwesterly
downslope winds of 10-15 mph are forecast behind a dry, secondary
cold frontal passage, with minimum RH of 20-30% (locally lower)
expected. This combination of winds/RH is expected to support
elevated fire weather concerns across much of the Southeast this
afternoon.
...Portions of New Mexico into eastern Arizona...
Low to mid-level moisture return is forecast across southern Texas
into portions of the Southwest through this afternoon. Although
forcing for ascent will remain modest under an upper-level ridge, a
combination of localized orographic ascent, deeply mixed boundary
layers with minimal inhibition, and a weak, subtle mid-level
shortwave trough will support isolated thunderstorm development this
afternoon. Slow storm motions (around 10 kts) will likely support
pockets of wetting precipitation, but PWAT values of 0.4-0.7" atop a
dry sub-cloud layer will likely support dry lightning strikes while
largely limiting precipitation. With regional ERCs near the 75th to
80th percentile, lightning ignitions appear possible. While
prevailing flow is forecast to remain weak, gusty outflow winds may
create erratic fire behavior with any new ignitions.
...Portions of the Upper Midwest...
A tightened surface pressure gradient will promote sustained
southwesterly winds of 20-25 mph, with the potential for gusts to
30-35 mph, across portions of the Upper Midwest, especially across
the eastern Dakotas and much of Minnesota. RH values are forecast to
fall to 25-30% this afternoon, with lower values possible should
forecast cloud cover clear more quickly this morning/afternoon. This
combination of wind/RH may promote locally elevated fire weather
concerns this afternoon, especially in pockets of drier fine fuels.
Recent precipitation across portions of this area along with
marginal fuel receptiveness and uncertainty regarding cloud cover
preclude the addition of Elevated highlights at this time.
..Chalmers.. 04/20/2026
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 200629
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0129 AM CDT Mon Apr 20 2026
Valid 211200Z - 221200Z
...Synopsis...
Upper-level ridging will gradually slide east over the Great Plains
on D2/Tuesday as a closed upper-level low moves onshore across the
West Coast. At the surface, high pressure will build into the
Southeast while a frontal system advances across the northern Great
Plains and Upper Midwest.
...Portions of Florida into southern Georgia...
Sustained easterly winds of 10-15 mph along the southeastern
periphery of high pressure building into the Southeast will overlap
reduced RH of 20-30% across much of the Florida Peninsula and into
southern Georgia Tuesday afternoon. Continued dry conditions amid
extreme to exceptional drought continues to promote receptive fuels
across this region, with ERCs currently at or above the 95th
percentile. This combination is expected to support elevated fire
weather concerns for at least a few hours. While winds are currently
forecast to remain below critical criteria, locally critical
conditions may be possible given the dryness/receptiveness of fuels
and potential for occasional wind gusts to 20 mph.
..Chalmers.. 04/20/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 192144
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0444 PM CDT Sun Apr 19 2026
Valid 211200Z - 271200Z
...Synopsis...
A large scale upper trough will move onshore the West Coast as
ridging slides over the eastern CONUS on Day 3/Tuesday.
Precipitation will be possible for parts of the Mid-Atlantic and
northern Appalachians with an associated shortwave trough on Day
4/Wednesday. However, much of the Piedmont into the Southeast will
remain fairly dry through the week as surface high pressure builds
across the region through Day 6/Friday. As the aforementioned trough
and associated mid-level flow progress eastward into the northern
Plains mid-week, fire weather concerns are expected to reemerge
across portions of the Southwest and High Plains. Through the end of
the forecast period, persistent western troughing will likely
maintain continued fire weather concerns where dry fuels exist.
...Day 3-5/Tuesday-Thursday...
...Florida, Mid-Atlantic, and Southeast...
A fire weather threat will continue for portions of Florida on Day
3/Tuesday as surface high pressure settles into the Deep South.
Breezy easterly winds of up to 10 mph (gusts up to 15 mph) and RH
values between 15-30 percent amid 90-99th percentile ERCs support
40% Critical probabilities. On Day 4/Wednesday, a shortwave impulse
will bring precipitation chances across portions of the Mid-Atlantic
along a weak cold front. Ahead of the front, strong mid-level flow
aloft will support dry and breezy downslope conditions where
97th-99th percentile ERCs have been observed across the Carolinas.
40% Critical probabilities have been introduced to account for this
threat.
...Central and Southern Plains...
A deepening surface low across the northern High Plains ahead of the
approaching upper-level trough and associated southwest flow aloft
will bring a more expansive fire weather threat to much of the High
Plains and portions of the Southwest mid-week where fuels remain
receptive. 70% critical probabilities have been maintained for Day
4/Wednesday where a mid-level jet aligns with tightening surface
pressure gradients associated with the deepening lee trough.
Downslope enhanced drying and stronger west/southwest winds will
continue across much of the Southwest and Southern Plains on Day
5/Thursday as the mid-level trough ejects into the Plains. Broad 40%
critical probabilities were maintained for the Southwest and
Southern Plains.
..Elizalde-Garcia.. 04/19/2026
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