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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 200647
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0147 AM CDT Sat Jun 20 2026
Valid 201200Z - 211200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE NORTHEASTERN GREAT
BASIN FOR SCATTERED DRY THUNDERSTORMS...
...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE EASTERN GREAT BASIN
INTO THE FOUR CORNERS FOR DRY AND WINDY CONDITIONS...
...Synopsis...
Zonal mid-level flow will overspread the CONUS today, with multiple
embedded impulses poised to traverse the zonal flow from the Pacific
Northwest to the mid-Mississippi Valley. At least one pronounced
mid-level impulse will overspread the Great Basin during the
afternoon hours, encouraging surface troughing over the Interior
West, resulting in dry/windy conditions over the Great Basin toward
the Four Corners region. Strong westerly mid-level flow behind the
mid-level impulse will overspread the Cascades, supporting
dry/breezy conditions over and to the lee of the higher terrain.
Finally, deep-layer ascent and enough mid-level moisture (hence
buoyancy) accompanying the passing mid-level impulse will encourage
high-based thunderstorm development from northern California to
western Wyoming. The combination of these meteorological scenarios
will support widespread wildfire ignition and/or growth concerns
across much of the Intermountain West today.
...Eastern Great Basin to the Four Corners region...
By afternoon peak heating, the aforementioned surface lee troughing
will support widespread southwesterly surface winds in the 15-25 mph
range amid 5-15 percent RH. Widespread Elevated highlights have been
continued, with Critical highlights in place where guidance shows
the highest likelihood of 20+ mph winds and 5-10 percent RH
overlapping for several hours. Across both Elevated and Critical
highlights, ERCs should easily exceed the 80th percentile, and thus
would support wildfire spread.
...Along and to the lee of the Cascades...
Strong flow westerly flow along the higher terrain, along with
downslope flow to the lee of the Cascades, will result in 15-25 mph
sustained westerly surface winds coinciding with RH as low as 15
percent in spots. Stronger surface winds and lower RH may occur in
localized, terrain favoring areas. Either way, the aforementioned
ambient surface conditions and dry fuels warrant Elevated
highlights.
...Far northern California to far western Wyoming...
During the afternoon, diurnal heating, upper support, and orographic
lift will all support at least isolated thunderstorm development
amid precipitable water values around 0.75 inches. Given dry fuels
and potentially light rainfall accumulations with some of the storm
cores, a few cells may be associated with efficient
lightning-induced ignitions given cloud-to-ground strikes,
warranting isolated dry thunderstorm highlights. Across northeastern
portions of the Great Basin, storms closer to stronger mid-level
flow may move faster, potentially supporting a regionally greater
lightning-ignition rate given dry fuels and a lesser chance for
rainfall accumulations. As such, scattered dry thunderstorm
highlights have been continued.
..Squitieri.. 06/20/2026
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 200654
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0154 AM CDT Sat Jun 20 2026
Valid 211200Z - 221200Z
...Synopsis...
Zonal mid-level flow will persist over the CONUS, with embedded
impulses continuing to traverse this flow tomorrow (Sunday). Surface
low development over the southern High Plains will encourage dry
westerly surface flow over portions of the Desert Southwest. By
afternoon, 15+ mph sustained westerly surface winds and 5-10 percent
RH atop dry fuels will promote conditions favorable for wildfire
spread, hence the introduction of Elevated highlights. Channeled
flow within the Snake River Plain will also support Elevated
dry/windy conditions by afternoon. Here, sustained westerly surface
winds are expected to exceed 15 mph for at least a few hours as RH
dips below 15 percent.
..Squitieri.. 06/20/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 192151
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0451 PM CDT Fri Jun 19 2026
Valid 211200Z - 271200Z
...Synopsis...
The upper level trough contributing to ongoing fire weather risk
will move onshore and weaken as it traverses the Great Plains. This
transitions the western states into a brief period of zonal flow
aloft, though embedded shortwave troughs will continue to provide
impactful fire weather conditions, before ridging returns to the
Intermountain West. This pattern will reinforce unseasonably warm,
dry conditions and accelerate fuel drying across the region.
However, if the high persists long enough into the next week as is
currently indicated by forecast guidance, moisture will likely begin
to advect north and eastward over AZ and NM. Conversely, expansive
troughing will dominate the Northeast, sending periodic cold fronts
and widespread precipitation across the eastern United States to
suppress regional fire threats there.
...Day 3/Sunday...
...Southwest and northern Great Basin...
As the aforementioned mid level shortwave trough moves through the
Intermountain West and over the Great Plains, it will support lee
surface troughing which will enhance surface winds across portions
of the Southwest. Specifically, over western NM and far eastern AZ,
where dry westerly winds will coincide with critically dry fuels, an
area of 40 percent probability of Critical wind/RH remains in place.
Under a well mixed surface boundary layer, much of the Snake River
Plain over ID will also experience dry and windy conditions,
necessitating a targeted 40 percent probability of Critical wind/RH
there as well.
...Day 5/Tuesday...
...Southwest and southern Great Basin...
As high pressure builds over the Southwest, hot and dry surface
conditions will promote deep boundary layer mixing, contributing to
increased westerly surface winds. As such, an area of 40 percent
probability of Critical wind/RH was introduced over portions of
northern AZ and far southern UT.
...Day 6/Wednesday...
...Southwest...
Persistent high pressure over the Southwest will eventually lead to
increasing moisture wrapped in from the Gulf of California. It
appears that this moisture begins to reach eastern AZ and western NM
by mid next week. As is typical with this pattern, hot and dry air
at the surface will lag increasing moisture aloft, leading to high
based thunderstorms. Expect adjustments in time/space with future
forecast issuances as the timing and placement of this potential
moisture becomes more clear.
..Stearns.. 06/19/2026
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