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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 131646
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1146 AM CDT Wed May 13 2026
Valid 131700Z - 141200Z
...CRITICAL FIRE WEATHER AREA FOR NORTHEASTERN MONTANA INTO FAR
NORTHWESTERN NORTH DAKOTA...
...Northeastern Montana...
Virga showers are currently moving through central MT ahead of a
sharp mid-level short wave, with little to no impact on surface
conditions. Southeasterly winds ahead of a deepening lee trough
across southern Alberta into north-central MT will continue to
increase the afternoon, reaching 20-25 mph by the peak afternoon
heating. Current RH of 20-25% will fall into the 15-20% range by
this afternoon. The dry and breezy conditions atop receptive fuels
will yield a critical fire weather threat for much of northeastern
MT.
The mid-level short wave, associated jet streak and increasing
mid/upper level moisture pushes into western/central MT by this
afternoon, supporting high-based showers and thunderstorms across
portions of the northern Rockies and central MT. A dry, sub-cloud
boundary layer will inhibit significant rainfall accumulation within
the fast moving thunderstorm cores as well as promoting strong to
severe downburst winds. Latest forecast guidance suggests a
prolonged convective event, lasting into the evening, affecting much
of northeastern MT. Fuels remain more receptive across northern MT
which could support some lightning ignitions as high-based
thunderstorms move into the northern High Plains this evening.
Therefore, Isolated Dry Thunderstorm Highlights have been extended
into northeastern MT.
A broad fire weather threat remains across much of the Intermountain
West and portions of the Great Plains as the vigorous upper wave
across the Northern Rockies translates eastward. Please see previous
discussion for more details.
..Williams.. 05/13/2026
.PREV DISCUSSION... /ISSUED 1238 AM CDT Wed May 13 2026/
...Synopsis...
A robust upper-level short wave trough and associated increased
west-southwest flow aloft will enter the Pacific Northwest and
Northern Rockies today. Wedged between western U.S. troughing and an
amplifying longwave trough over the eastern U.S., upper ridging will
slide over the Rocky Mountain region. Associated with the
substantial mid-upper level pattern, a rapidly evolving lee-side low
in the southern Canadian Prairies will deepen lee surface troughing
over the Great Basin and High Plains while southwesterly flow ahead
of the trough increases. This will present a multifaceted fire
weather setup across portions of the Intermountain West.
...Northern Montana...
Deepening surface troughing across the southern Canadian Prairies
into central MT will usher in stronger southerly to southeasterly
winds of 15-20 mph along with RH reductions of 20-30 percent,
promoting broad Elevated fire weather concerns. Critical highlights
were maintained where an alignment of RH of 20 percent or below and
winds of 20-25 mph are expected across northeastern MT and far
western ND atop receptive fuels. Increasing mid-level moisture ahead
of the upper trough and arrival of a Pacific cold front should
promote isolated to scattered showers and initially high-based
thunderstorms across much of northwestern MT Wednesday where IsoDryT
highlights have been maintained.
...Southwest, Upper Snake River Plain and Colorado River Basin...
As the sharp upper trough and associated mid-level jet shifts over
ID into western MT, deepening surface troughing across the northern
Great Basin and stronger southwesterly flow ahead of the trough will
bring expansive fire weather concerns to much of the Intermountain
West. Dry and breezy southwesterly flow of 15-25 mph (localized 30
mph in the eastern Great Basin) and RH of 10-15 percent will align
with drying fuels to promote elevated fire weather conditions across
portions of the Great Basin and CO River Basin into central WY.
Forecast thermodynamic profiles (with a prominent dry boundary
layer) will support isolated high-based showers and thunderstorms
over higher terrain of western NM, far eastern AZ, central UT, and
southwest WY into the Upper Snake River Plain. Various stages of
green up and mixed curing fuels has resulted in a complicated
fuelscape, resulting in expansive Elevated highlights and a broader
IsoDryT risk area.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 131949
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Wed May 13 2026
Valid 141200Z - 151200Z
...Northern Plains...
An upper-level trough and associated stronger mid-level westerly
flow push into the Northern Plains Day 2/Thursday. At the surface,
strong post frontal westerly winds of 15-25 mph and low RH will
align with dry fuels and RH of 20-30% to support an elevated fire
weather threat across the Dakotas. Farther west, more pronounced
deep-layer westerly flow will yield sustained west winds of 30-45
mph across central and eastern MT during peak afternoon heating,
although limited RH reductions, some expected rainfall through
tonight and green up across southern MT should mitigate an otherwise
critical fire weather environment. Elevated highlights were
generally expanded eastward, farther into ND/SD and central NE based
on latest forecast guidance.
...Southwest and Southern High Plains...
Westerly downslope flow of 15-20 mph amid RH of 15-20% will bring
elevated fire weather concerns from far southeastern AZ, much of
southeastern NM into the OK and TX Panhandles. Delayed green up has
allowed receptive fuels to remain in place. A subtle mid-level short
wave is expected to eject into the southern High Plains Thursday.
The dry downslope trajectories behind a dry line will keep a dry,
sub-cloud boundary layer in place through early afternoon. The
arrival of the mid-level perturbation and associated surface low
evolution across southwestern KS, in addition to sufficient
mid-level moisture and afternoon destabilization, should result in
isolated, high based showers and thunderstorms across much of the TX
Panhandle into the OK Panhandle and adjacent CO/KS areas. Minimal
rainfall, gusty outflow winds and some lightning ignitions are
possible in existing dry fuels.
..Williams.. 05/13/2026
.PREV DISCUSSION... /ISSUED 1240 AM CDT Wed May 13 2026/
...Synopsis...
An upper level low will traverse the central United States/Canada
border as a long wave trough across the Eastern Seaboard transitions
to a closed low. Upper ridging will slide over the High Plains and
Upper Midwest, gradually flattening as the Canadian upper low moves
east. At the surface, a strong dry cold front extending south of a
central Canadian surface low will bring widespread fire weather
concerns to the northern/central Plains. A surface low will emerge
over the TX/OK Panhandles, tightening surface pressure gradients
east of the CO/NM higher terrain thus enhancing downslope flow and
deep layer mixing to promote a broad fire weather threat. Increasing
mid-level moisture and subtle forcing associating with an
approaching short wave impulse could aid in high-based thunderstorm
development across portions of the OK/TX Panhandles.
...Northern Plains...
Following the passage of a powerful cold front, a robust mid-level
jet and deep westerly flow will promote fire weather concerns across
the region. Modest RH of 20-30 percent and west winds of 30-45 mph
are possible with higher gusts across the Plains of MT and terrain
favored areas in central and eastern WY. A widespread transition to
green up over southeastern MT into the Dakotas may somewhat mitigate
fuel receptivity. However, in areas with minimal green up and/or
mixed receptive fuels, locally critical fire weather conditions may
emerge where RH could decrease below 15 percent.
...Southwest and Southern High Plains...
Westerly downslope enhanced flow of 15-20 mph and RH reductions of
less than 20 percent amid a dry fuelscape will promote Elevated fire
weather conditions across the region. Farther east, increasing
mid-level moisture along with afternoon heating and resultant
instability should support isolated thunderstorms across the OK/TX
Panhandles on Thursday afternoon, where an IsoDryT risk area has
been introduced.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 132153
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0453 PM CDT Wed May 13 2026
Valid 151200Z - 211200Z
...Synopsis...
An embedded short wave within broader westerly mid-level flow will
move into the Upper Midwest by Day 3/Friday. Robust west winds at
the surface in the wake of a departing deep surface low in Ontario
will bring keep a fire weather threat across much of the Northern
Plains and Upper Midwest Friday. A more subtle mid-level
perturbation ejects into the Southern Plains Friday as an associated
lee surface low develops across the High Plains, supporting dry and
breezy conditions and enhanced fire weather concerns. A multi-day
fire weather threat is likely across portions of the Southwest and
Southern Plains as a larger scale trough sets up over the western
U.S. with persistent southwest flow aloft bolstering lee trough
formation across the Southern Plains.
...Day 3/Friday...
...Northern Plains...
Dry and breezy westerly flow in the wake of a cold front will likely
enhance fire weather concerns across portions of eastern MT into the
Dakotas and western Minnesota, where fuels remain receptive.
However, changes to current Day 3/Friday forecast are possible
depending on rainfall distribution from Day 2/Thursday.
...Southern Plains...
A swath of enhanced southwest winds will likely develop south of a
lee surface low across the TX Panhandle across portions of the
southern High Plains Friday. Enhanced downslope drying as the subtle
short wave aloft shifts into the Southern Plains along with breezy
southwest winds and dry fuels should promote a fire weather threat
amid dry fuels. 40% critical probabilities were introduced across
southeastern NM and adjacent far West TX, northeastward into far
southwestern OK.
...Day 4-7/Saturday-Tuesday...
Fire weather concerns shift mainly into portions of the Southwest
and Southern Plains as a larger scale upper trough anchors over
western CONUS for the weekend into early next week. Persistent
southwesterly flow aloft will aid in lee trough development across
the Southern Plains, driving dry and breezy conditions over the
Southwest and southern High Plains.
...California...
Stronger northwest flow on the backside of the trough with an
accompanying Pacific cold front shifts southeastward over the
weekend. Dry, post frontal flow funneling through the CA Central
Valley should bring a fire weather threat to this region on Day
5/Sunday as finer fuels and grasses dry leading up to the stronger
northerly/northwesterly wind event. 40% critical probabilities were
added to the CA Central Valley to cover this potential threat.
..Williams.. 05/13/2026
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