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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 151632
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1132 AM CDT Wed Apr 15 2026
Valid 151700Z - 161200Z
...Southern High Plains...
The eastern extent of the Elevated risk area has been trimmed back
slightly across western OK and the TX Rolling Plains. This is to
account for recently observed precipitation, marginal fuels, and
lighter surface winds during peak heating. In the lee of the
southern Rockies, poor overnight humidity recoveries are expected to
further exacerbate the local fire environment. Morning observations
portray 30 mph wind gusts and less than 25 percent RH in gap flow
areas with clear skies overhead. As deeper mixing occurs this
afternoon, RH is expected to bottom out around 10 percent locally
atop very dry fuels.
...Eastern WY/NE Panhandle/southwestern SD...
Westerly winds of 10-20 mph combined with RH of 20-25 percent will
promote locally elevated fire weather conditions for a few hours
this afternoon in sporadic areas that did not see recent
precipitation. Increasing mid-level cloud cover this afternoon is
expected to maintain marginal RH values, precluding the introduction
of Elevated highlights.
The rest of the forecast remains on track, see the previous
discussion for more information.
..Elizalde-Garcia/Williams.. 04/15/2026
.PREV DISCUSSION... /ISSUED 1252 AM CDT Wed Apr 15 2026/
...Synopsis...
The upper-level trough will depart the southern Plains through the
day today. A weak lee trough will develop in the High Plains. Dry
return flow will continue in the southern Appalachians/Mid-Atlantic.
...Southern High Plains...
Modest mid-level winds across the southern Rockies will promote a
weak lee trough to the east. Surface winds of 15 to locally 20 mph
are possible amid a dry airmass (10-20% RH by the afternoon).
Elevated fire weather is expected given continued lack of rainfall
and dry fuels.
...Southern Appalachians into the Mid-Atlantic...
Dry and breezy conditions are expected during the afternoon as
temperatures warm into the mid 80s to low 90s F. RH of 25-35% is
probable for most areas, but values closer to 20% may occur locally.
Very dry fuels will support an elevated fire weather threat.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 151935
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0235 PM CDT Wed Apr 15 2026
Valid 161200Z - 171200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL/SOUTHERN
PLAINS...
...Central/southern High Plains...
Critical fire weather highlights have been introduced across eastern
CO into portions of the southern High Plains. Sustained
southwesterly winds of 15-25 mph (gusts up to 30 mph) amid 10-15
percent RH (single digits locally) are expected atop very dry and
receptive fuels, increasing critical fire weather concerns. While
high clouds are anticipated later in the afternoon, ongoing poor
humidity recoveries and dry/breezy conditions on Day 1/Wednesday
will promote an earlier start to the fire environment on Day
2/Thursday. Farther north, Elevated highlights have been expanded to
encompass much of the High Plains. Widespread south/southwesterly
winds of up to 20 mph and RH of 15-20 percent will overspread a
region of 80th-95th percentile ERCs. An abrupt northerly wind shift
is expected as a sharp cold front progresses southeastward in the
early evening, potentially impacting active fires. However, chances
for light precipitation, colder temperatures, and increasing RH will
provide relief to the fire environment overnight for much of the
central High Plains.
...Mid-Atlantic/Piedmont...
Elevated highlights have been trimmed to only include areas east of
the Appalachian Mountains as latest model guidance suggests higher
RH trends Thursday afternoon in the eastern TN Valley. Otherwise,
the forecast remains on track as multiple days of above normal
temperatures and dry/breezy conditions have contributed to very dry
fuels with widespread 90th-99th percentile ERCs. Southwesterly winds
of 10 mph or greater (gusts of 20+ mph) and 25-35 percent RH will
support elevated fire weather concerns across the region.
..Elizalde-Garcia/Williams.. 04/15/2026
.PREV DISCUSSION... /ISSUED 1255 AM CDT Wed Apr 15 2026/
...Synopsis...
An upper-level trough will dig into the southern Great Basin/Four
Corners on Thursday. A modest subtropical jet stream will develop
across northern Mexico into the southern Plains. At the surface, a
strong low pressure system will deepen in the vicinity of the Black
Hills. A fairly strong cold front will progress southward into the
central Plains.
...Southern New Mexico into central High Plains...
This region will generally exist in between the developing southern
stream jet and the digging trough to the northwest for most of the
period. Some increase in mid-level winds may occur by late
afternoon, however. A very dry airmass is expected. RH could
approach single digits locally, but will more broadly be 10-20%.
This is forecast despite increasing mid/upper clouds with time. The
overall expectation is for elevated to near critical fire weather
conditions. Sustained critical could occur locally, but confidence
highlighting where this will occur remains low.
...Far eastern Wyoming into Nebraska/South Dakota...
As the surface low deepens, winds of 15-20 mph will be possible. RH
values of 10-20% will occur during the afternoon. The strongest
mid-level flow will generally remain farther west of the region
which should limit the potential for sustained critical conditions.
Further, the cold front is forecast to progress southward which will
lead to a stark shift to northerly winds and greater RH. Given the
strength of the front, the more southern frontal solutions have been
weighted higher in this forecast.
...Southern Appalachians into Mid-Atlantic...
The persistent dry return flow pattern will continue another day.
Temperatures in the mid 80s to low 90s F will again promote a broad
area of reduced RH values during the afternoon. 25-35% will again be
common, but areas near 20% are still possible. Winds will still be
somewhat weak at 10-15 mph, but very dry fuels will still support a
elevated fire weather threat.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 152153
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0453 PM CDT Wed Apr 15 2026
Valid 171200Z - 231200Z
...Synopsis...
On Day 3/Friday, an amplifying trough will move into the central
U.S. as an associated mid-level speed max will intensify over the
central Plains. Tightening surface pressure gradients and a strong
cold front will promote a concentrated fire weather threat over the
southern Plains. Across the eastern U.S., a shortwave impulse will
aid in the upper ridge breakdown as the aforementioned trough
traverses the Midwest. As above normal temperatures prevail,
exceptionally dry fuels and occasional elevated winds will pose a
lingering fire weather threat throughout the East through the
weekend. Temporary ridging builds across the West on Day 4/Saturday
as post-frontal surface flow drives a dry and breezy airmass across
much of the High Plains and portions of the Southwest. On Day
5/Sunday-Day 6/Monday, the upper ridge slides east of the Rockies as
the upper trough exits eastern CONUS, promoting dry return flow over
the Plains and post frontal winds in the Southeast. Towards the end
of the forecast period, another deep trough is forecast to approach
western CONUS. While model discrepancy exists in the extended, fire
weather concerns will likely continue next week in regions that have
seen minimal precipitation.
...Portions of the Central/Southern Plains - Day 3/Friday through
Day 5/Sunday...
An amplified upper-level trough approaches the central CONUS on Day
3/Friday. The associated mid-level jet streak and deepening lee
surface troughing across the central Plains will aid in strong
west/southwest winds behind the persistent dry line. 70% Critical
probabilities have been trimmed slightly to account for quicker cold
frontal progression than previously forecast. Combined probabilities
of less than 15 percent RH and greater than 20 mph winds ahead of
the front should maintain a critical fire weather threat. An abrupt
wind shift of gusty northerly winds behind the aforementioned cold
front has the potential to impact any new or ongoing wildfires
through the evening hours.
On Day 4/Saturday, locally elevated fire weather conditions may
arise in a dry post-frontal airmass, though uncertainty in frontal
timing and overlap of stronger winds and lower RH precludes the
introduction of probabilities at this time. As the amplified upper
trough exits the region on Day 5/Sunday, surface troughing across
High Plains and surface high pressure centered over east TX will
promote dry return flow for much of the region. Given the overall
pattern and ensemble guidance agreement in low RH and stronger
winds, 40% Critical probabilities have been maintained.
...Mid-Atlantic/Piedmont/Southeast - Day 3/Friday through Day
5/Sunday...
As the East Coast upper ridge breaks down on Day 3/Friday, the
potential for a downslope wind event exists in the lee of the
Appalachians. West/northwesterly winds will traverse the Blue Ridge
Mountains allowing for surface RH to drop as surface winds increase
along the Piedmont, resulting in a continuation of 40% Critical
probabilities. On Day 4/Saturday, dry southwesterly flow returns to
the Piedmont and broader Southeast as the surface low enters
southern Ontario. With no expected precipitation across the region,
40% Critical probabilities have been maintained where dry and breezy
conditions continue atop exceptionally dry fuels. Chances for
precipitation increase on Day 5/Sunday as the upper trough moves
overhead, which could alleviate broader fire concerns. However, the
extent of wetting rainfall is uncertain, precluding the introduction
of probabilities at this time. On Day 6/Monday, post-frontal
northeasterly flow may increase fire weather concerns across the
Southeast as drought conditions worsen. However, uncertainty in
precipitation chances along the front on Day 5/Sunday preclude the
introduction of probabilities at this time.
As a secondary upper trough develops over the western U.S. on Day
6/Monday-Day 7/Tuesday, subsequent dry southerly flow over parts of
the Southwest and lee surface troughing across the High Plains will
continue broader fire weather concerns towards the end of the
forecast period.
..Elizalde-Garcia/Williams.. 04/15/2026
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