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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 121612
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1112 AM CDT Tue May 12 2026
Valid 121700Z - 131200Z
No changes to the outlook were necessary. Dry, post-frontal flow is
still expected to bring an elevated fire weather concern to parts of
the northern and central Plains. North to northwest winds of 20-30
mph with higher gusts near 45 mph are occurring across eastern
ND/SD. The limited RH reductions this afternoon of 25-30% (locally
20%) amid a mixed fuelscape as green up expands across the Plains
should mitigate the impact of otherwise robust north/northwest winds
today. Please see previous forecast discussion for details.
..Williams.. 05/12/2026
.PREV DISCUSSION... /ISSUED 0129 AM CDT Tue May 12 2026/
...Synopsis...
An upper level low will approach the northwestern U.S. coastline as
troughing and an associated mid-level low traverse the Upper Midwest
and Great Lakes region. Between surface high pressure centered over
southern MT and an eastward propagating surface low towards the
Great Lakes, tightened pressure gradients will encourage strong
deep-layer northwesterly flow to overspread a well-mixed
post-frontal airmass across the mid-upper Missouri Valley.
While RH reductions will be modest in the post-frontal airmass
(around 20-30 percent), 15-25 mph sustained northwesterly winds
(localized gusts up to 35 mph) amid very dry fuels will support
Elevated fire-weather conditions. A swath of stronger sustained
northwest winds between 20-30 mph (localized gusts up to 45 mph)
will impact the eastern Dakotas into the mid-upper Missouri Valley.
However, this corridor of stronger winds will be displaced to the
east of a warmer, drier boundary layer and atop fuels recently
transitioning to green up. While RH values are expected to remain
above 25 percent within this region, locally critical fire weather
conditions may emerge in areas of stronger winds and lower RH.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 122002
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0302 PM CDT Tue May 12 2026
Valid 131200Z - 141200Z
...CRITICAL FIRE WEATHER AREA FOR NORTHEASTERN MONTANA INTO FAR
NORTHWESTERN NORTH DAKOTA...
...Northern Montana...
A robust upper-level short wave trough and associated increased
southwest flow aloft will enter the Pacific Northwest and Northern
Rockies Wednesday, bringing widespread fire weather concerns to much
of the Intermountain West. A deepening surface trough across the
southern Canadian Prairies into central MT will usher in stronger
southerly to southeasterly winds of 15-25 mph ahead of the trough.
These winds, along with RH as low as 20-30% amid dry fuels will
promote heightened fire weather threat in portions of the central
and northern Plains. Alignment of RH of 20% or below and winds of
around 25 mph is most likely across northeastern MT and far western
ND where fuels are more receptive.
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. Latest forecast guidance suggests higher rain amounts
(greater than 0.10") across portions of north central MT. Thus,
isolated dry thunderstorm highlights were trimmed across
north-central MT and shifted slightly southeastward, where fast
northeastward storm motions of 35-45 mph and less thunderstorm
coverage will limit potential for wetting rains.
...Southwest, Upper Snake River Plain and Colorado River Basin...
An expansive fire weather threat remains across much of the
Intermountain West as the upper-level trough and attendant
increasing southwest winds aloft shifts into the Pacific North
west. Dry and breezy southwesterly flow of 15-25 mph (localized 30
mph in the eastern Great Basin) and RH of 10-15% will align with
drying fuels to promote elevated fire weather conditions across
portions of the Great Basin, 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
mountain chain into southwest WY.
..Williams.. 05/12/2026
.PREV DISCUSSION... /ISSUED 0132 AM CDT Tue May 12 2026/
...Synopsis...
An upper level low will move onshore the Pacific Northwest and
transform into an open trough as it moves farther inland. 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 and deepening lee surface troughing over the Great Basin
and High Plains will present a multifaceted fire weather setup
across portions of the Intermountain West.
...Northern Montana...
In the southern Canadian Prairies, a rapidly evolving lee low will
promote a dry return flow pattern across the northern High Plains. A
Critical fire weather risk was introduced for northeastern MT and
far northwestern ND where sustained southeasterly winds of 20-25 mph
and 15-20 percent RH will overlap an exceptionally dry fuelscape.
Widespread south-southeasterly winds of 15-20 mph amid 20-25 percent
RH will promote elevated fire weather concerns across much of
central-eastern MT. Fast moving, high based showers and
thunderstorms with limited precipitation are expected across central
and northern MT as broader ascent materializes ahead of an incoming
trough. Resultant instability and a dry boundary layer could
encourage a few lightning ignitions where receptive fuels exist. An
IsoDryT area was introduced to account for this threat.
...Portions of the Southwest into the 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 fire weather concerns to much of the Intermountain West.
Southwest winds of 15-25 mph amid very low RH and drying fuels under
successive days of abnormally high temperatures will support an
Elevated fire weather threat across the region. Daytime instability
and increasing mid-level moisture will promote high based convection
along the higher terrain of the Four Corners through central WY into
the Wyoming Basin. Sporadic lightning ignitions are possible where
drier fuels exist, promoting an IsoDryT area.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 122209
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0509 PM CDT Tue May 12 2026
Valid 141200Z - 201200Z
...Synopsis...
An upper-level trough ejects into the northern Plains on Day
3/Thursday while a surface low shifts into Manitoba. At the surface,
a strong, dry cold front extending south of the low sweeps into the
Upper Midwest bringing widespread fire weather concerns to portions
of the northern Plains and central High plains. Breezy west winds
and dry conditions should linger over portions of the northern
Plains and Upper Midwest on Day 4/Friday as the surface low
translates eastward into Ontario. A large scale upper trough enters
the western U.S. by the end of the weekend bringing a fire weather
threat, including breezy southwest winds and very dry conditions, to
portions of the Great Basin and Four Corners regions on Day
5/Saturday, shifting into the Southwest by Day 6/Sunday.
...Day 3/Thursday...
...Northern Plains...
Strong, deep layer westerly winds behind a powerful cold front under
a similarly robust mid-level jet will bring a fire weather threat to
much of Northern Plains on Day 3/Thursday. West winds of 35-45 mph
are possible with higher gusts across the Plains of MT and terrain
favored areas in central and eastern WY. A mixed fuels picture
across the region, including green up across southeastern MT and ND,
could somewhat mitigate the fire environment precluding introduction
of 70% critical probabilities within the expanded 40% area.
...Southwest and Southern High Plains...
Surface lee troughing over the TX Panhandle under modest westerly
flow aloft will promote enhanced southwesterly winds from southern
NM into the OK/TX Panhandles Day 3/Thursday. A subtle embedded short
wave feature shifting into Southern Plains could aid in high-based
thunderstorm development across portions of the OK/TX Panhandles,
with deeper boundary layer moisture shunted to the east. A 10% dry
thunderstorm probability was introduced.
...Day 4/Friday - Northern Plains...
Dry, post-frontal westerly flow will continue to bring fire weather
concerns to portions of the Northern Plains on Day 4/Friday. Fuels
remain largely receptive although notable green up in some areas may
suppress wildfire spread potential.
Day 5-6/Saturday-Sunday - Great Basin, Four Corners and Southwest...
A larger scale trough impinges upon the western CONUS by the
weekend, reintroducing dry conditions and breezy southwest winds
into the Great Basin and Four Corners regions by Day 5/Saturday. As
the trough migrates eastward, the fire weather threat shifts into
the Southwest on Day 6/Sunday, where several days of drying could
support a more receptive fuelscape for wildfire spread.
..Williams.. 05/12/2026
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