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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 111631
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1131 AM CDT Sat Apr 11 2026
Valid 111700Z - 121200Z
...Eastern Wyoming into the Central High Plains...
An approaching mid-level short wave and associated increasing shear
and instability aloft in conjunction with a dry and well mixed
sub-cloud layer, will support quick moving isolated showers and dry
thunderstorms with minimal precipitation this afternoon across
southeastern WY and portions of the central High Plains today. An
evolving lee surface trough will also promote dry and breezy
conditions across much of eastern WY, southwestern SD and
northwestern NE as southwest winds of 15-20 mph and relative
humidity in the 15-20% range align over receptive fuels. Elevated
highlights were extended westward to include downslope favored areas
in the lee of the Bighorn Mountains in north-central WY based on
current surface observations and short term model guidance.
...Southern Great Basin...
Dry and breezy conditions are expected under passing mid-level short
wave and associated enhanced southwest flow aloft.
Southwest winds of around 15 to 20 mph and relative afternoon
humidity of 10-15% within a deep, well-mixed boundary layer will
support elevated fire weather conditions for portions of the
southern NV, UT and northern AZ today. However, marginal fuel
receptiveness should limit wildfire spread potential which precluded
introduction of Elevated highlights.
...Southeast...
A very dry air mass coupled with exceptionally dry fuels will
persist across much of the Southeast today under an upper-level
ridge. Relative humidity falling to 20-30% by mid-afternoon (locally
15% in the Piedmont regions of northern GA and western SC) will be
common across the region. However, a diffuse surface pressure
gradient in place will support light surface and boundary layer
winds through the afternoon, limiting a more significant fire
weather threat.
..Williams.. 04/11/2026
.PREV DISCUSSION... /ISSUED 0137 AM CDT Sat Apr 11 2026/
...Synopsis...
Broad mid-level toughing over the Western U.S. with an embedded
shortwave will be responsible for both isolated dry thunderstorms
and dry/breezy conditions across portions of eastern Wyoming into
the Central High Plains.
...Eastern Wyoming into the Central High Plains...
Broad southwesterly flow and a weak embedded jet streak associated
with a mid-level shortwave trough will overspread the Rockies,
resulting in lee troughing and a developing/deepening surface low
over eastern Montana. Dry and breezy boundary layer conditions will
overspread receptive fuels across eastern Wyoming into far western
South Dakota/Nebraska and portions of far northern Colorado, with
surface winds of 15-20 MPH and relative humidity of 15-20%. Dry
thunderstorm potential will overlap these Elevated fire-weather
concerns owing to deep, dry, and well-mixed boundary layer profiles
resulting in limited precipitation efficiency amidst an otherwise
convectively unstable regime.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 111946
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0246 PM CDT Sat Apr 11 2026
Valid 121200Z - 131200Z
...Southwest and Four Corners...
Increasing southwest flow aloft on the southern and southeastern
periphery of a closed upper-level low over northern CA will
overspread the Desert Southwest and Four Corners Sunday. Dry and
well-mixed boundary layer conditions will support southwest surface
winds of 15-20 mph amid 15-20% afternoon relative humidity across
much of eastern UT the Four Corners and into the lowland deserts of
southeastern AZ and southwestern NM. Brief critical fire weather
conditions including southwest winds of 20 mph with higher gusts and
RH of around 10% are possible across southeastern AZ where fuels are
still marginally receptive.
...Central High Plains...
Increasing southwesterly flow aloft over the Colorado Plateau, lee
surface troughing across the central High Plains and minimal
rainfall from convection through tonight will support a favorable
dry, downslope regime for Sunday across the high plains of CO and
WY. Elevated highlights were extended westward along the CO Front
Range where locally critical but brief fire weather conditions
including southwest winds of around 20 mph and RH reductions to 10%
are possible in favored terrain gaps. Farther north, a departing
surface low across the Upper Midwest will enhance westerly winds
across southwestern SD and western NE where west winds of 10-20 mph,
RH falling to between 15-20% and dry fuels should align resulting in
an elevated fire weather threat.
...Southern High Plains...
Increasing westerly flow aloft and surface lee troughing across the
Southern High Plains should support dry and breezy conditions across
much of eastern NM Sunday. However, some rainfall is expected across
NM tonight, which could mitigate fire weather concerns for the
D2/Sunday period. However, an extension of elevated highlights may
be warranted in subsequent forecast updates if rainfall extent and
duration is minimal.
...Ohio River Valley/Middle Mississippi Valley...
Southerly to southwesterly winds will increase Sunday across the OH
River and middle MS River Valleys as surface high pressure slides
eastward off the Mid Atlantic Coast. The dry return flow pattern
should yield south/southwest winds of 10-15 mph coupled with a dry
boundary layer supportive of minimum relative humidity of 25-35% by
mid-afternoon. Exceptionally dry fuels with ERC values in the 95th
to 99th percentiles amid ongoing drought combined with the dry and
breezy conditions will promote an elevated fire weather threat for
much of the OH River Valley. Latest model guidance warrants an
expansion of Elevated highlights into the middle MS River Valley and
northern MS/AL area.
..Williams.. 04/11/2026
.PREV DISCUSSION... /ISSUED 0139 AM CDT Sat Apr 11 2026/
...Synopsis...
A mid-level closed low is forecast to progress from the northern
California coast into the Intermountain West, with broad
west-southwesterly flow overspreading the Four Corners into the
Great Plains on Sunday. Widespread dry and breezy conditions are
expected, resulting in several areas of Elevated fire-weather
highlights.
...Four Corners/Central High Plains...
While represented by separate Elevated highlights, much of the area
from southern Arizona/New Mexico into eastern Colorado/Wyoming and
portions of western/central Nebraska and southern South Dakota will
experience widespread dry and breezy conditions. Though fuels across
portions of Arizona and New Mexico are more marginally receptive to
ignition and spread, winds of 15-20 MPH and relative humidity as low
as 10% will support at least Elevated wildfire concerns. Further
east into the Central High Plains, fuels are largely at or exceeding
the 98th annual ERC percentiles with winds forecast at 15-20 MPH and
relative humidity at 10-15%. Locally Critical conditions may occur
across areas just east of the Front Range of the Rockies, where
topography results in an enhancement of the surface winds, or
perhaps where a stronger downslope component of the winds develop.
However, uncertainty in the duration and magnitude of Critical winds
precludes highlights at this time. While meteorological conditions
will reach Elevated status in the gap between these areas, recent
wetting rainfall and less than receptive fuels will lessen the
overall fire-weather concerns between the highlights.
...Ohio River Valley...
While forecast relative humidity values are more variable, ranging
from 25-35%, much of the lower Ohio River Valley is experiencing
widespread moderate to severe drought. Fuels at or exceeding the
98th annual percentile for ERCs and southerly surface winds around
15 MPH will support Elevated fire-weather concerns amidst deeply
mixed and dry boundary layer profiles. While instances of light to
moderate precipitation may occur the prior afternoon/evening, this
will do little to alleviate the overall fire-weather concerns.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 102211
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0511 PM CDT Fri Apr 10 2026
Valid 121200Z - 181200Z
...Synopsis...
On Day 3/Sunday, an upper-level low is forecast to move onshore in
northern California as an upper-level ridge strengthens over the
central and eastern CONUS. A lee-surface low ejects off the Rockies
on Day 4/Monday, slowly shifting across the Midwest and Great Lakes
region by Day 6/Wednesday. This scenario is likely to result in
multiple days of precipitation across the West and from Texas
through the Great Lakes, which would temporarily dampen fire weather
threats. Continued upper-level ridging through Day 5/Tuesday across
the eastern CONUS will promote above normal temperatures and drying
conditions for much of the region, though increased chances of
precipitation may return towards the end of next week as the upper
trough shifts east.
...Ohio River Valley - Day 3/Sunday...
Increasing potential for 10-15 mph southerly winds and 30-40 percent
RH will present fire weather concerns across northeastern AR into
portions of the Ohio River Valley. Given recently observed
widespread ERCs above the 90th percentile and low fine fuel
moisture, 40 percent probabilities for Critical fire weather have
been maintained. The expanse of the drawn area may be adjusted in
future outlooks as guidance evolves the northward extent of gulf
moisture advection.
...Central/Southern Plains and Southwest - Day 3/Sunday through Day
4/Monday...
Fire weather conditions return on Day 3/Sunday as an amplified upper
trough moves into the West and an associated shortwave traverses the
High Plains. Dry southwesterly flow and strong winds will overlap
portions of the Southwest that have not seen recent appreciable
rainfall, thus 40 percent probabilities of Critical fire weather
conditions have been introduced to the region. Wedged between a
surface low to the north and lee surface troughing to the south,
strong westerly winds and low RH atop recently receptive fuels will
promote fire weather concerns across the upper central Plains.
Farther south in CO, the foothills and plains east of the Rockies
will experience a mix of downslope and dry return flow. Strong
west-southwesterly winds and critically low RH support fire weather
conditions, and will likely precondition finer fuels for a continued
fire weather threat over the next few days. 40 percent probabilities
of Critical fire weather have been introduced to account for this
threat.
Beneath the large upper trough, tight surface pressure gradients Day
4/Monday will further enhance dry and windy conditions behind the
dryline in the central/southern High Plains. Despite precipitation
forecast earlier in the forecast period across eastern NM and the TX
Panhandle, accelerated drying on Day 3/Sunday will likely
precondition the fire environment by decreasing fine fuel moisture,
escalating broader fire weather concerns. Recent lightning across
portions of these areas may see the emergence of holdovers and
growth on existing fires given expected dry/windy conditions. 40
percent probabilities of Critical fire weather have been maintained
to account for these concerns. A smaller area of 70 percent
probabilities for Critical fire weather conditions was introduced on
Day 4/Monday for southeastern CO to account for an overlap of
stronger winds and lower RH.
...Southern Plains and portions of the Southwest - Day 5/Tuesday...
As the large scale trough shifts east and lee cyclogenesis occurs
east of the Rockies, gusty surface winds will continue over a dry
airmass in the southern Plains and parts of the Southwest. Given
multiple days of fire weather conditions over the area, 40 percent
Critical probabilities have been introduced.
..Elizalde-Garcia/Nauslar.. 04/10/2026
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