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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 071603
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1103 AM CDT Tue Jul 07 2026
Valid 071700Z - 081200Z
...Morning Update...
The Elevated and Isolated Dry Thunderstorm risk areas were slightly
adjusted based on the latest observations and forecast guidance.
High resolution guidance depicts greater instability enveloping the
IsoDryT region today as compared to yesterday, indicating an
increased threat for more widespread thunderstorm development this
afternoon. Although, residual smoke and morning mid/high level cloud
cover could inhibit thunderstorm coverage across the central CO
Rockies. 00z soundings from GJT, SLC, LKN, and BOI observed a range
of PWAT values at 0.7-0.95", higher than what yesterday's 12/18z
model guidance anticipated. As a result, thunderstorms will likely
be a wet/dry mix this afternoon where forecast soundings depict
slower storm motions along the West Slope; however, a very dry
boundary layer (especially at lower elevations) will continue to
favor evaporation, thus less precipitation efficiency. The potential
for deep pyroconvection remains in the vicinity of the IsoDryT area
on active large fires, as shown by the Babylon Fire yesterday
afternoon, which produced a pyroCb pulse in a similar atmospheric
environment. See the previous discussion for more information.
..Elizalde-Garcia.. 07/07/2026
.PREV DISCUSSION... /ISSUED 1259 AM CDT Tue Jul 07 2026/
...Synopsis...
The upper-level high will begin to extend and shift westward from
the Southwest to coastal southern California. Upper-level heights
will rise across much of the West through the day, but an
upper-level trough will approach the Pacific Northwest coast late in
the period. The onshore surface pressure gradient across the
Cascades will strengthen with lee troughing to the east of the
Cascades and extending down along the northern Sierra. A thermal
trough will extend out of the Desert Southwest into the central
Great Basin.
Isolated to scattered mixed wet/dry thunderstorms will develop
across portions of the northern Great Basin and extend to the Four
Corners region. PWAT values of 0.5-0.9" associated with mostly
mid-level moisture across the region along with a deep, well mixed
boundary layer and storm motions of 15-25 knots will help limit
precipitation. A weak mid-level disturbance is forecast to move
across portions of the Great Basin, which will help increase storm
development and organization and lead to potentially severe outflow
winds.
Wetter storms are likely, especially from central/northeast Oregon
extending into northern Utah, but the IsoDryT area was maintained
given the likelihood of mixed wet/dry thunderstorms, receptive
fuels, and likely scattered thunderstorm coverage. Smoke in Colorado
into the Four Corners could inhibit thunderstorm development and
will be monitored for the Day 1 update. Isolated high-based
thunderstorms are possible overnight in portions of eastern
Washington, but too much forecast uncertainty exists to include an
additional IsoDryT area.
Westerly sustained winds of 12-20 mph gusting 20-30 mph amid minimum
RH of 12-25% are likely in portions of the Cascades Gaps onto the
Columbia Basin and from south-central Oregon extending south along
the Sierra Front. Southwest sustained winds of 12-20 mph gusting
20-30 mph amid minimum RH of 5-15% are expected across the southern
Great Basin/vicinity. These conditions will be more pronounced along
thermal trough extensions and under slightly stronger mid-level flow
(20-30 knots).
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 071904
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0204 PM CDT Tue Jul 07 2026
Valid 081200Z - 091200Z
...Afternoon Update...
The Elevated risk area has been expanded along and east of the
Sierra Nevada where high resolution forecast guidance depicts 70-90%
probabilities of wind/RH reaching criteria. Enhanced westerly flow
aloft should encourage downslope flow off the higher terrain,
promoting gusts up to 30 mph amid 8-15% RH where ERCs are
approaching the 80-90th percentile. In addition, Isolated Dry
Thunderstorm highlights were expanded more into the Snake River
Plain where a dry boundary layer, ample instability, and dry fuels
have increased concerns for potential lightning ignitions. The rest
of the forecast remains on track, see the previous discussion for
more information.
..Elizalde-Garcia.. 07/07/2026
.PREV DISCUSSION... /ISSUED 0101 AM CDT Tue Jul 07 2026/
...Synopsis...
An upper-level trough will move into southwest Canada helping to
flattening the ridge over the West and increasing west/southwest
flow aloft across the northwestern US. The upper high will extend
and shift westward over the southwestern US and off the southern
California coast. A weak, Pacific cold front will move through the
Northwest into the northern Great Basin.
Westerly sustained winds of 12-20 mph with gusts of 20-30 mph amid
minimum RH of 12-25% are likely across portions central/eastern
Washington as the onshore pressure gradient remains enhanced. As the
Pacific cold front moves southeast, winds will increase along and
ahead of it across much of the Great Basin into the Four Corners.
West-southwest sustained winds of 12-20 mph with gusts of 20-30 mph
amid minimum RH of 5-15% are expected across this area. These dry
and breezy conditions will be following multiple days of lightning
across portions of the Great Basin, with holdovers likely to emerge.
Isolated to scattered mixed wet/dry thunderstorms are likely from
northeast Nevada/southern Idaho extending east-southeast to the West
Slope. This will be on the southern/western periphery of the
residual mid-level moisture that has tracked over the Intermountain
West the past few days. Fuels remain near to record dry across
portions of Utah and Colorado, and multiple large wildfires remain
very active, with a history of pyroCb development in similar
environments.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 072119
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0419 PM CDT Tue Jul 07 2026
Valid 091200Z - 151200Z
...Synopsis...
This week exhibits a critical fire weather pattern for portions of
the Intermountain West with thunderstorms followed by dry and breezy
conditions later in the week, generating a favorable environment for
the emergence of possible holdover lightning ignitions. An
upper-level trough will move into southwest Canada Day
2-3/Wednesday-Thursday, with zonal westerly flow and a flattened
ridge over the northern half to two-thirds of the West. A weak dry
cold front will push through the Northwest and into the Great Basin
on Day 3/Thursday, with residual moisture and above normal
temperatures ahead of it. Moisture will push east of the Colorado
Rockies and be suppressed southward to southern Arizona and New
Mexico beyond Day 4/Friday as a ridge builds across the western
CONUS. Forecast uncertainty exists late in the period regarding how
an upper-level trough off the Pacific Northwest coast will interact
with the likely building upper-level ridge over most of the West,
especially the Intermountain West Day 6/Sunday and beyond. Some
ensembles do indicate thunderstorm potential early next week across
portions of central CA and the Sierra Nevada, where fuels will
continue to dry out this weekend out under hot and dry conditions.
Guidance will be monitored closely for dry thunderstorm
probabilities in future outlook cycles.
...Days 3-5/Thursday-Saturday...
Dry and breezy conditions continue on Day 3/Thursday across the
southern Great Basin into the Four Corners. Following several days
of mixed wet/dry thunderstorms, these conditions could promote the
emergence of any holdover lightning ignitions. Some residual
mid-level moisture could promote a few daytime isolated showers over
the eastern Great Basin and northwestern CO, though decreased
instability (compared to previous days) precludes dry thunderstorm
probabilities. An upper-level ridge will build across the
western/central CONUS later this week, amplifying through the
weekend. Meanwhile, upper troughing should persist over the Pacific
Northwest, further enhancing southwesterly flow aloft and dry
downslope flow over the northern Sierra Nevada into the southern
Cascades. 40% Critical probabilities have been maintained on Day
4-5/Friday-Saturday where guidance depicts dry and windy conditions
atop dry fuels. The spatial extent of drawn probabilities may be
adjusted in future outlooks as extended guidance becomes better
resolved.
..Elizalde-Garcia.. 07/07/2026
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