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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 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 261913
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0213 PM CDT Wed Aug 26 2026
Valid 271200Z - 281200Z
...CRITICAL FIRE WEATHER AREA FOR FAR NORTHEASTERN
CALIFORNIA...NORTHWESTERN NEVADA...SOUTHEASTERN OREGON...
No changes were made to the ongoing forecast. Isolated to scattered
wet/dry thunderstorms are expected to develop over the Northern
Rockies into the adjacent Montana plains on Day 2/Thursday. Fuels
have grown increasingly more receptive, as proven by recently
established wildfires within the landscape. An upgrade to a
Scattered Dry Thunderstorm risk was considered across portions of
the Montana higher-terrain; however, greater moisture influence in
the following days may increase fuel moisture, providing relief to
the environment. In addition, various guidance depicts increasing
mid/high-level clouds in the morning and early afternoon hours,
which could limit solar insolation and thus limit coverage of
afternoon thunderstorms. Nevertheless, lightning ignitions will
remain a concern across much of the outlined region, alongside
strong to severe wind gust potential (see the Day 2 Convective
Outlook for more details). The rest of the forecast remains on
track, please see the previous discussion for more information.
..Elizalde-Garcia.. 08/26/2026
.PREV DISCUSSION... /ISSUED 0111 AM CDT Wed Aug 26 2026/
...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.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 262153
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0453 PM CDT Wed Aug 26 2026
Valid 281200Z - 031200Z
...Synopsis...
An upper ridge currently centered over the Four Corners region will
begin to gradually translate eastward towards the Southeast this
weekend, while a series of shortwave troughs impact the Pacific
Northwest. Strong southwest-westerly flow will continue across the
northwestern CONUS into early next week, with embedded disturbances
within persistent upper troughing and along the northern periphery
of the flattening ridge. Long term guidance suggests these
shortwaves will contribute to the breakdown of the upper ridge,
shunting monsoonal moisture to the south and east. However,
increasing moisture influence from ingested tropical remnants in the
Pacific could support thunderstorm chances out West this weekend,
though confidence remains low. 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
6/Monday.
...Northwest, Northern Great Basin and Northern Rockies...
Drier southwest flow aloft associated with perpetual troughing over
the northwest CONUS will promote continued fire weather concerns
into early next week. 40% Critical probabilities have been
maintained with minor adjustments for Days 3-4/Friday-Saturday, and
introduced across northeastern California, northwestern Nevada, and
southeastern Oregon on Day 6/Monday. West to southwest winds of
15-20 mph and afternoon relative humidity of 15-20 percent will
bring daily elevated fire weather concerns, potentially impacting
nascent wildfires born from thunderstorm activity early in the
forecast period (especially across northwest/north-central Montana
on Day 3/Friday). Despite decreasing high temperatures (as compared
to the previous week) with the much anticipated departure of
large-scale upper ridging, breezy winds and low RH will preserve a
very dry fuelscape.
...Southern California...
Above average daytime temperatures and poor humidity recoveries are
forecast across portions of southern California through the 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 maintained on Day 3/Friday, but withheld for Day
4/Saturday due to uncertainty in the strength of the offshore
pressure gradient.
..Elizalde-Garcia.. 08/26/2026
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