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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 061655
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1155 AM CDT Sat Jun 06 2026
Valid 061700Z - 071200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN AND
SOUTHWEST...
The northern extent of the Elevated area over WY was expanded
commensurate with the latest forecast guidance showing the hot, dry,
and windy conditions progressing farther northeast today. Very
localized extremely critical conditions will be possible this
afternoon over terrain-favored areas of southwest UT. The certainty,
areal extent, and limited duration preclude the introduction of any
drawn areas with this morning's update. However, portions of this
same area will likely see Elevated conditions exceeding 18 hours of
duration today into tonight. Satellite imagery over much of the
highlighted areas shows fully sunny skies this morning with
scattered low and mid-level clouds over much of the central Rockies.
Surface observations are also showing southwest winds beginning to
exceed 15 mph across portions of UT and WY combined with RHs in the
single digits to mid-teens already this morning. A quick-moving
thunderstorm or two is not out of the question for northern UT
tonight, but the threat doesn't appear widespread or certain enough
to include a drawn risk area. The rest of the forecast remains on
track as previously described.
..Stearns.. 06/06/2026
.PREV DISCUSSION... /ISSUED 0205 AM CDT Sat Jun 06 2026/
...Synopsis...
An intensifying upper trough over the Northwest is forecast to
spread eastward into the Northern Rockies and southern Canada today
and tonight. A lee low is forecast to deepen over the northern Great
Basin and northern MT before moving northward into southern Canada.
Stronger flow aloft will move southeastward, overspreading a dry and
hot air mass over much of the western US. This will promote
widespread elevated and critical fire-weather conditions atop dry
fuels from the Great Basin to the Southwest. Isolated dry
thunderstorms are also possible as moisture increases across the
central Rockies and High Plains.
...Great Basin and Southwest...
As the upper trough over the Northwest and northern Rockies
intensifies, two belts of stronger mid-level flow will overspread
portions of the Great Basin and central Rockies. This, along with an
enhanced surface pressure gradient from the deepening lee low in
northern MT will bolster surface winds to 20-30 mph from
northeastern NV southward into UT, northern AZ and western CO. In
combination with high temperatures and low RH of 10-20%, widespread
elevated and critical fire-weather conditions are expected amid a
dry fuelscape.
Locally critical conditions may also extend across northern and
western NV into far southern OR along the lee of the Sierras.
Several hours of gusty surface winds (20-25 mph) and RH below 20%
are expected this afternoon. However, less receptive fuels, owing to
greater rainfall in the past 2 weeks, suggests critical conditions,
while possible, will be more localized.
Weaker flow aloft across southern AZ and the Four Corners will still
promote widespread elevated conditions with 10-20% RH and surface
gusts of 15-25 mph. Potentially enhanced by local terrain, some
potential for brief critical conditions may develop given drying
fuels and increasing burn period duration.
...ID and Northern Rockies...
Ascent from the upper trough will impinge on the western edge of
modest surface moisture moving westward into the higher terrain near
the lee low and surface trough. This ascent and diurnal heating
could support isolated thunderstorm development across eastern ID
and far southwestern MT. Likely high-based, these fast-moving storms
would have limited precipitation efficiency and some potential for
drier strikes. However, forecast coverage is likely to remain sparse
and areas where storms are more likely to develop have fuels that
are less receptive to starts.
...Central High Plains...
As westerly flow aloft overspreads the Rockies, enhanced lee trough
will aide in marginal low-level moisture transport across the
central High Plains and Front Range. Isolated thunderstorms are
possible across parts of northern CO and southern WY and western NE.
Fast storm motions, and high cloud bases suggest these storms are
unlikely to support widespread rainfall. With pockets of drier fuels
present, isolated dry thunderstorms and lightning starts are
possible.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 061916
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0216 PM CDT Sat Jun 06 2026
Valid 071200Z - 081200Z
...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN GREAT
BASIN...SOUTHWEST...AND CENTRAL ROCKIES...
...CRITICAL FIRE WEATHER AREA FOR THE SNAKE RIVER PLAIN...
An area of Isolated Dry Thunder was introduced over portions of
central/northern UT and western WY on Day 2/Sunday near the
previously mentioned frontal boundary. Isolated thunderstorm
coverage amid a significant sub-cloud dry layer, combined with
limited precipitable water near 1/2 inch, and quick storm motion
near 25-35 kts over receptive fuels will lead to the threat of dry
lightning ignitions in the morning hours and again by peak heating
in the early/mid afternoon hours.
Regarding the surface wind/RH threat, a few small changes were made.
The Critical area was expanded over much of northeast AZ as the
latest forecast guidance has trended toward strong winds over this
region amid the hot and very low RHs. Keep in mind that should
ignitions occur over this region, burn periods will continue to
extend well into the overnight hours with RHs failing to rise above
20-30% in almost all drawn areas of the southern Great Basin and
Southwest. The larger Elevated area was also expanded over much of
the Mojave Desert as well as northern NM and across much of the
Front Range of the central Rocky Mountains. With this expansion,
there are high elevation portions of the central Rocky Mountains
included that are may struggle to meet wind/RH criteria amid less
critically dry fuel conditions. The targeted Elevated to Critical
threat across portions of the Snake River Plain remains on track
from previous forecast issuances.
..Stearns.. 06/06/2026
.PREV DISCUSSION... /ISSUED 0159 AM CDT Sat Jun 06 2026/
...Synopsis...
The upper-level low over the Northwest will advance towards the
Northern Rockies, as a surface low intensifies over the northern
Plains with the trailing cold front moving through the northern
Great Basin. This will bolster surface winds across parts of the
Southwest and central Rockies mid a very dry air mass. Elevated to
critical fire-weather conditions are likely.
...Southern Great Basin and central Rockies...
Beneath the stronger flow loft, gusty surface winds are again likely
ahead of the cold front from southern NV, into UT, parts of western
CO and southwestern WY. Aided by deep mixing and 30-40 kt of
southwest flow aloft, afternoon surface winds of 20-30 mph are
expected. Poor to nonexistent overnight humidity recoveries and
afternoon minimums of 5 to 15 percent will exacerbate critical fuels
across the Southern Rockies and Southwest. The combination of very
dry air, strong winds and receptive fuels will favor several hours
of widespread critical conditions Sunday afternoon.
...ID...
Beneath the upper trough, continued strong southwesterly flow aloft
will bolster surface winds through the Snake River Plains and
southern ID. Gusty surface winds of 20-35 mph and RH of 10-20% will
support several hours of elevated to critical fire-weather
conditions Sunday. Gusty wind and low humidity may extend farther
eastward into ID and far western WY, but here fuels here have
received recent rainfall and are less receptive.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 062156
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0456 PM CDT Sat Jun 06 2026
Valid 081200Z - 141200Z
The initial upper-level trough dominating the western CONUS will
move through southern Canada and the Northern Rockies, dragging a
weak cold front across the Great Basin and nearby regions. The
atmosphere transitions into a brief holding pattern as this system
departs and another trough arrives over the Pacific Northwest.
Broad, persistent southwest winds will continue over across the
Southwest and the Great Basin as the next, less amplified trough
moves through the upper level flow. Behind the second trough,
ridging is modeled to build in over the west coast. This would raise
temperatures back above normal for much of the Pacific Northwest and
relax pressure gradients (weaken winds) as next weekend approaches.
...Day 3/Monday and Day 4/Tuesday...
Clear skies and deep atmospheric mixing will drive strong afternoon
warming, dropping relative humidity down to 5 to 15 percent yet
again over much of the southern Great Basin, Southwest, and nearby
Rocky Mountain area. This dry air will overlap with localized winds
gusting between 15 and 25 mph. 70% probabilities for Critical fire
weather remains firmly in place across southern UT and northern AZ,
expanding slightly into western CO and southern WY. Surrounding
areas, including southeastern NV, central WY, and portions of
southern CA and AZ face a 40% likelihood of critical wind/RH
conditions where grass, brush, and timber are dry and receptive to
fire. Additionally, thunderstorms amid a dry sub-cloud layer,
limited precipitable water, and fast moving storm motion in portions
of southeast WY, far western NE, and northeast CO will lead to a 10%
chance of Isolated Dry Thunder. The threat is very similar once
again on Day 4/Tuesday, but winds appear to be a bit more widespread
over the Front Range and portions of the central/northern High
Plains. This is particularly concerning given the possibility of dry
lightning in this same area preceding this increased wind/RH threat.
...Day 5/Wednesday through Day 7/Friday...
As the aforementioned second broader trough spreads moves across the
northern CONUS, the combination of highest winds and lowest RHs will
be focused slightly farther south over portions of the southern
Great Basin and northern Southwest on Day 5/Wednesday through Day
7/Friday. The latest model consensus maintains the best potential
for potential critical conditions over northern AZ and NM.
..Stearns.. 06/06/2026
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