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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 231624
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1124 AM CDT Sun Aug 23 2026
Valid 231700Z - 241200Z
...Southern Plains...
Much needed rainfall in the last 24 hours has occurred across
portions of northwest TX and the TX Panhandle with isolated
accumulations up to one inch. This residual moisture along with
winds not exceeding 15 mph will temporarily reduce fire weather
concerns across this area this afternoon. Thus, reduced southern
extent of existing Elevated Highlights over portions of northwest
TX. Isolated high-based thunderstorms still pose a threat for new
ignitions over very dry fuels across the northern TX Panhandle and
adjacent OK border areas this afternoon and early evening as a
mid-level short wave enters the region.
...Northern Intermountain West and northern Rockies...
The forecast remains on track with no changes implemented for this
update. Please see previous discussion for more details.
..Williams.. 08/23/2026
.PREV DISCUSSION... /ISSUED 0156 AM CDT Sun Aug 23 2026/
...Synopsis...
A robust midlevel trough will advance eastward across parts of the
Northwest and northern Rockies today. Farther south, an expansive
upper ridge will remain centered on the southern Rockies. Along the
northeastern periphery of the ridge, a low-amplitude shortwave
trough will track southeastward across the central/southern Plains.
...Northern Intermountain West and northern Rockies...
Diurnal heating and related boundary-layer mixing beneath a
well-established midlevel moisture plume (sampled by 23/00Z observed
soundings) will contribute to marginal destabilization across the
region. As large-scale forcing for ascent preceding the midlevel
trough overspreads this instability, isolated to widely scattered
high-based thunderstorms will move from west to east through the
day. Fast storm motions and the well-mixed boundary layer
(characterized by inverted-V profiles) will favor a mix of wet/dry
thunderstorms. Given dry fuels across the area, lightning-induced
ignitions will be a concern. Some of these storms may evolve into
organized clusters and pose a risk of severe wind gusts and hail --
especially with eastward extent into parts of central MT. See the
SPC Day 1 Convective Outlook for more information on the severe
risk.
Additionally, breezy westerly surface winds will overspread the
region along/behind an eastward-moving cold front. These breezy
winds combined with 15-25 percent RH will lead to an elevated fire
risk.
...Southern High Plains...
Aided by an evolving surface low in the vicinity of the OK
Panhandle, dry/breezy southerly return flow will develop across the
southern High Plains, resulting in elevated conditions (given
increasingly dry/receptive fuels). Furthermore, the passing midlevel
impulse will promote high-based, eastward-moving thunderstorms
during the afternoon and evening hours. Isolated ignitions will be
possible with this activity, given limited expected rainfall.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 231918
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0218 PM CDT Sun Aug 23 2026
Valid 241200Z - 251200Z
...Northern Great Basin...
A subtle upper-level wave still off the CA coast will glance through
northern CA and the northern Great Basin D2/Monday. This feature
along with a transient mid/upper level moisture plume and increasing
afternoon instability, will promote isolated high-based convection
across portions of northern NV, southeast OR, southwest ID and far
northeast CA Monday afternoon and early evening. A dry, well-mixed
boundary layer and faster shower/thunderstorm trajectories should
limit surface precipitation and promote an increased ignition
potential amid a receptive fuelscape.
...Southern Plains...
Dry west/southwest flow south of an emergent surface low across
western OK will bring elevated fire weather conditions to the
Rolling Plains of northwest TX and far southwestern OK on D2/Monday.
Although some rainfall has occurred in parts of northwest TX, above
normal temperatures in the lower 100s and relative humidity
reductions to around 15 percent by peak afternoon heating will
quickly dry out overall dormant/cured fine fuels. The existing
Elevated Highlights were shifted slightly southward based on latest
model guidance.
..Williams.. 08/23/2026
.PREV DISCUSSION... /ISSUED 0158 AM CDT Sun Aug 23 2026/
...Synopsis...
Embedded within a belt of enhanced southwesterly flow aloft, a
subtle/low-amplitude wave will overspread parts of the northern
Great Basin. Here, sufficient midlevel moisture atop a diurnally
deepening boundary layer will promote isolated high-based
thunderstorms across parts of northern NV, southeast OR, southwest
ID, and far northeast CA during the afternoon and early evening. PW
values around 0.6 inches will favor mostly dry thunderstorms, which
will pose a risk of isolated lightning-induced ignitions, given a
dry/receptive fuelscape (90th-95th percentile ERCs).
Farther south, a surface low will evolve eastward across parts of
the southern Plains during the day. A tightening pressure gradient
peripheral to this feature will aid in the development of 15-20 mph
sustained west-southwesterly surface winds across parts of the TX
South Plains into southwest OK during the afternoon. These winds,
combined with 15-20 percent RH, will lead to elevated fire-weather
conditions.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 232133
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0433 PM CDT Sun Aug 23 2026
Valid 251200Z - 311200Z
...Synopsis...
An upper-level ridge extending northward from broad high pressure
across the Southwest will bring warmer and drier conditions to much
of the Northwest and Northern Rockies. Dry southwesterly flow aloft
and departure of deeper monsoon moisture will keep fire weather
concerns in the form of dry and breezy conditions for portions of
the Great Basin and Columbia Basin for the middle of the week,
reaching the central ID mountains by Day 5/Thursday as fuels dry.
The threat of dry thunderstorms returns to the northern Rockies Day
4/Wednesday with the arrival of an upper-level trough into the
Pacific Northwest. Diurnal showers/thunderstorms along higher
terrain will likely shift eastward, mainly along the Rockies by the
end of the week with another possible upper-level wave entering the
Pacific Northwest by the weekend, although forecast uncertainty
increases during this time frame.
...Northwest, Northern Great Basin and Northern Rockies...
A drier southwest flow pattern will bring a multi-day fire weather
threat back into portions of the northwestern U.S., with fire
weather concerns extending eastward into the central ID mountains
later this week as fuels recover from recent monsoon moisture. The
40 percent critical probabilities have generally been expanded for
Days 3-5/Tuesday-Thursday, with additional threat areas for both
Days 6-7/Friday-Saturday. West to southwest winds of 15-20 mph and
afternoon relative humidity between 15-20 percent will bring at
least daily elevated fire weather concerns to this region. Critical
fire weather conditions with winds of 20+ mph are likely but only in
localized areas, particularly from northeastern CA into far
northwestern NV and southeastern OR where afternoon relative
humidity reached 10 percent under more robust mid-level flow.
Enhanced onshore flow develops across the Pacific Northwest as the
next upper-level trough impacts the region midweek. This will
bolster downslope drying across the Columbia Basin where afternoon
relative humidity reductions of around 15 percent are possible. This
dry atmospheric and fuel environment, coupled with west/southwest
winds of 15-20 mph, will likely bring a fire weather threat for the
Columbia Basin both Wednesday and Thursday.
...Dry Thunderstorms...
The arrival of the next upper-level wave will bring additional
opportunities for afternoon showers and thunderstorms across the
northern Rockies on Day 4/Wednesday. The eastward shunting of deeper
monsoon moisture under a drier southwest flow regime and building
ridge over the northern Rockies on Day 3/Tuesday will likely
contribute to a drying boundary layer in advance of the next
mid/upper wave on Day 4/Wednesday. This should set the stage for at
least isolated high-based thunderstorm development over the northern
Rockies Wednesday afternoon where fuels will have undergone two days
of drying. Given the modest mid-level moisture with PWATs less than
0.8", widespread thunderstorm activity is not expected at this time
with a 10 percent probability area maintained.
..Williams.. 08/23/2026
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