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U.S. & Canada 12-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 261635
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1135 AM CDT Wed Aug 26 2026
Valid 261700Z - 271200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHEASTERN
CALIFORNIA...NORTHWESTERN NEVADA...AND SOUTHEASTERN OREGON...
As an upper trough impinges upon the Pacific Northwest this
afternoon, strong southwesterly flow aloft will support an expansive
fire weather threat across the northern Intermountain West. A
tightening surface pressure gradient along the Cascades and emerging
surface low will compel sustained southwest winds of 10-15 mph
(gusts of 20-30 mph in terrain-favored areas) and RH values of
15-20% in the Columbia Basin and northern Sierra Nevada. A region of
critical conditions are likely across northeastern California,
northwestern NV, and southeastern Oregon where RH values will
decline to less than 15% and sustained southwest winds increase to
20 mph. Notably, in the last 48 hours, numerous lightning strikes
occurred with minimally observed precipitation (less than 0.15")
within today's Critical risk area and southern extent of the
Elevated highlights, increasing concerns for holdovers to emerge.
Fuels remain receptive across much of the region, with active fires
in the landscape and observed ERCs ranging from the 90-95th
percentile.
12z REFS/HREF continue to depict 50-60% probabilities of
thunderstorms across the Northern Rockies this afternoon. Forecast
soundings portray deep inverted-V profiles, MUCAPE vales up to 1200
J/kg, and LCL-EL winds of 25-35 kt; as a result, accumulating
precipitation at the surface is expected to be minimal, escalating
the potential for lightning-induced ignitions within an increasingly
receptive fuelscape. Isolated Dry Thunderstorm highlights were
trimmed out of far northeastern Washington where afternoon
thunderstorms have become less probable.
Farther south, offshore winds will redevelop this evening in
portions of southern California. Elevated fire weather conditions
are expected in favored terrain gaps and downslope areas of
LA/Ventura/Santa Barbara counties. Please see the previous
discussion for more details.
..Elizalde-Garcia.. 08/26/2026
.PREV DISCUSSION... /ISSUED 0107 AM CDT Wed Aug 26 2026/
...Synopsis...
An upper-level trough edging into the Pacific Northwest will bring
widespread fire weather concerns to much of the interior of the
Northwest, northern Great Basin and northern Rockies today. Isolated
dry thunderstorms are expected across much of the northern Rockies,
while dry and breezy conditions develop farther west across the
Columbia Basin south towards the northern Great Basin and
northeastern CA. An increasing offshore pressure gradient will bring
an elevated fire weather threat to parts of southern CA late this
afternoon into the overnight hours as dry and breezy conditions
develop.
...Northeastern California into northwestern Great Basin...
A narrow corridor of critical fire weather conditions is likely
today across the northwestern fringe of the Great Basin. The
upper-level trough and attendant increasing deep layer southwest
flow will support southwest surface winds of around 20 mph. An
existing dry air mass with RH falling to as low as 10% and receptive
fuels will promote wildfire spread, where several active fires are
present.
...Columbia Basin southward towards the northern Great Basin and
northern Sierra Nevada...
An upper trough encroaching upon the Pacific Northwest will
strengthen mid-level southwest winds across much of the northwestern
U.S. today. Although upper-level cloud cover will inhibit full
mixing potential across the region, the deep-layer southwest flow
aided by an emerging surface low across eastern WA/OR will
contribute to southwest winds of 10-15 mph from northeastern CA into
eastern OR and the Columbia Basin. Relative humidity reductions by
peak afternoon heating will likely reach around 15%.
...Northern Rockies into northern Washington...
The approaching upper trough will promote broad but diffuse forcing
for ascent as a mid/upper moisture plume pushes into the northern
Rockies. Afternoon instability (MLCAPE values in the 500-1000 J/kg
range), a dry sub-cloud layer and northeast shower/thunderstorm
trajectories of 25-35 mph with PWATs generally less than 0.8",
should limit surface rainfall this afternoon and evening as isolated
dry thunderstorms develop across the central ID mountains northward
into the ID Panhandle and western MT.
...Southern California...
High pressure aloft will continue to support dry conditions and near
record high temperatures in the 90s and 100s farther inland away
from coastal influence. Fuels continue to dry, becoming increasingly
receptive each day. An offshore pressure gradient will promote
primarily north winds of 15-25 mph amid RH of 15-20% this evening
into early D2/Thursday morning. Winds will be strongest in favored
terrain gaps and downslope areas in LA/Ventura/Santa Barbara
counties.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 260611
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0111 AM CDT Wed Aug 26 2026
Valid 271200Z - 281200Z
...CRITICAL FIRE WEATHER AREA FOR FAR NORTHEASTERN
CALIFORNIA...NORTHWESTERN NEVADA AND SOUTHEASTERN OREGON...
...Synopsis...
An upper-level trough moving into the Pacific Northwest will bring
an expansive fire weather threat to portions of the Northwestern
U.S., northern Rockies and northern Great Basin. Another round of
isolated dry thunderstorms is expected across the northern Rockies
into the MT high plains Thursday afternoon and evening. Dry and
breezy conditions south of the upper trough will promote fire
weather concerns for the Columbia Basin and much of southwest ID,
southeastern OR and the northern Great Basin. A zone of critical
fire weather conditions are expected across southeastern OR and
adjacent CA/NV where southwest winds will reach 20 mph at times.
...Southeastern Oregon, far northeastern California and adjacent
Nevada...
A corridor of enhanced southwest winds of 15-20 mph with higher
gusts will evolve as deep layer southwesterly flow increases south
of the mid/upper trough moving into the Pacific Northwest. A very
dry boundary layer emerges Thursday amid mostly clear skies, serving
to enhance boundary layer mixing and resultant stronger surface
winds. These winds, relative humidity as low as 10% and dry fuels
will support a rapid fire spread environment across far northeastern
CA, northwestern NV and parts of southeastern OR Thursday afternoon.
The critical fire weather conditions could also impact existing
wildfires within the highlighted area.
...Columbia Basin, northeastern California and northern Great
Basin....
The upper-level trough and associated increasing southwest flow will
continue to push farther into Pacific Northwest Thursday. Downslope
flow east of the Cascades will enhance drying in the Columbia Basin
where RH could reach 15% in some locations. The dry conditions
coupled with west/southwest winds of around 15 mph will promote
elevated fire weather conditions over receptive fuels.
...Northern Rockies...
The aforementioned upper-level trough, sufficient mid-level moisture
and daytime instability will aid in high-based thunderstorm
development once again across the northern Rockies and adjacent high
plains of MT Thursday afternoon/evening. Fast shower/thunderstorm
motions and a dry, sub-cloud layer should limit surface rainfall
accumulation, increasing ignition potential atop a dry fuelscape.
...Southern California...
Hot temperatures in the 90s to lower 100s under an upper high across
southern CA will promote increasingly dry fuels across the region.
An offshore pressure gradient will enhance mainly northerly winds,
particularly Thursday evening/night across wind prone areas of
LA/Ventura/Santa Barbara counties, leading to an elevated fire
weather threat.
..Williams.. 08/26/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 252200
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0500 PM CDT Tue Aug 25 2026
Valid 271200Z - 021200Z
...Synopsis...
An upper ridge will gradually translate eastward into the northern
Plains as a mid-level shortwave trough progresses through the
Pacific Northwest on Day 3/Thursday. Meanwhile, large-scale ascent
will overspread the Northern Rockies into central Montana, promoting
thunderstorm potential where dry fuels exist. A cold front will
sweep across the Columbia Basin, bringing strong winds and modestly
low RH values to a drought-stressed environment with numerous
ongoing wildfires on Day 3/Thursday. Strong southwest-westerly flow
will continue across the northwestern CONUS into the weekend, with
embedded disturbances within persistent upper troughing and along
the northern periphery of the flattening ridge. Long term guidance
suggests a secondary shortwave trough could enter the Northwest and
contribute to the breakdown of the upper ridge atop the Four Corners
this weekend. As a result of the upper pattern, fire weather
concerns will likely continue through the forecast period across the
parts of the Northwest, Great Basin and Northern Rockies. However,
low predictability and poor agreement among ensemble clusters
precludes additional probabilities beyond Day 5/Saturday.
...Dry Thunderstorms...
The arrival of the next upper-level wave will bring additional
opportunities for afternoon thunderstorms across portions of the
Northern Rockies and Montana plains on Day 3/Thursday. A dry
boundary layer and fast storm motions will favor evaporation and
less precipitation efficiency, raising concerns for
lightning-induced ignitions within an increasingly receptive
fuelscape. 10% Dry Thunderstorm probabilities were introduced on Day
3/Thursday, though may need to be confined in future outlooks where
multiple days of an overlapping thunderstorm threat could increase
recoveries.
...Northwest, Northern Great Basin and Northern Rockies...
A drier southwest flow pattern will bring a multi-day fire weather
threat to portions of the northwestern U.S., with fire weather
concerns extending eastward into the Montana plains later this week.
40% Critical probabilities have been maintained with minor
adjustments for Days 3-5/Thursday-Saturday, and introduced across
north/central Montana on Day 4/Friday. West to southwest winds of
15-20 mph and afternoon relative humidity between 15-20 percent will
bring daily elevated fire weather concerns, potentially impacting
nascent wildfires born from thunderstorm activity early in the
forecast period. 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 on Day
3/Thursday.
...Southern California...
Above average daytime temperatures and poor humidity recoveries are
forecast across portions of southern California through the
week/early weekend. Offshore flow will present overnight/early
morning periods of gusty winds and critically low RH values in Santa
Barbara/Ventura/LA counties amid very dry fuels, raising concerns
for locally elevated fire weather conditions. As such, 40% Critical
probabilities were introduced on Days 3-4/Thursday-Friday.
..Elizalde-Garcia.. 08/25/2026
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