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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 061633
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1133 AM CDT Mon Jul 06 2026
Valid 061700Z - 071200Z
...Morning Update...
The forecast remains on track for dry/windy conditions and isolated
dry thunderstorms across portions of the Four Corners and Great
Basin this afternoon. Residual mid-level moisture -- as portrayed by
REV's 12z sounding and various afternoon forecast soundings for the
rest of the region -- will interact with an ejecting shortwave
trough and daytime instability to develop high based convection. Dry
sub-cloud layers and 0.6-0.8" PWATs will encourage less
precipitation efficiency initially, maintaining lightning ignition
potential where critically dry fuels exist. A transition to a mixed
wet/dry thunderstorm threat will occur in the evening as PWATs
increase, most likely in northwestern NM and eastern AZ. See the
previous discussion for more information.
..Elizalde-Garcia.. 07/06/2026
.PREV DISCUSSION... /ISSUED 0120 AM CDT Mon Jul 06 2026/
...Synopsis...
A combination of dry thunderstorms and dry/windy conditions will
pose fire weather concerns for portions of the Four Corners and
northern Great Basin for today. Early-morning water-vapor imagery
continues to show an upper ridge over the Four Corners region with
an embedded shortwave trough evident across the northern Great
Basin. This feature will promote not only thunderstorm chances
across much of the Great Basin, but should also result in dry/windy
conditions across parts of NV, UT, and AZ.
...Dry Thunderstorms...
The 00 UTC MFR RAOB sampled a PWAT value of 0.96 inches, which is
higher than previously anticipated by model guidance. Consequently,
MRMS QPE and surface stations have reported pockets of wetting
rainfall up to 0.25 inches associated with thunderstorms across
southern OR late Sunday evening/early Monday morning. Regional
soundings further east into the Four Corners region sampled a drier
air mass (especially within the boundary layer), but GOES PWAT
imagery suggests higher-quality moisture is advecting northward into
western NV ahead of the upper-level disturbance. This will likely
favor wet thunderstorms across northern CA into southern OR where
most guidance shows a consistent signal for wetting rainfall, which
warranted removal from the dry thunderstorm risk area. A mix of wet
and dry thunderstorms across the CA/OR/NV tri-state region should
transition to predominantly dry thunderstorms with southeastward
extent towards the Four Corners region on the fringe of the
mid-level moisture plume. In general, fuels remain very dry across
the broader region and should support lightning ignitions outside of
where heavier precipitation cores have occurred (mainly over
northern NV/southern OR) over the past 12-24 hours.
...Eastern Nevada into Utah and Arizona...
Modest surface pressure falls across the northern Great Basin
through the afternoon will result in increasing southerly winds
across southeast NV into adjacent portions of UT and AZ. Latest
ensemble guidance continues to show reasonably strong probabilities
for sustained winds near 15 mph with gusts upwards of 20-30 mph.
Relative humidity values should fall to near 15% as temperatures
climb into the 90s, resulting in areas of elevated fire weather
conditions. While confidence in elevated conditions is greatest
across southeast NV into southwest UT, more aggressive solutions
suggests elevated conditions may extend into eastern UT.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 061906
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0206 PM CDT Mon Jul 06 2026
Valid 071200Z - 081200Z
...Afternoon Update...
Only slight adjustments were made to the risk areas based on the
latest guidance. Notably, the Isolated Dry Thunderstorm risk area
was expanded into southern ID where a mix of wet/dry thunderstorms
will pose a risk for lightning ignitions where pockets of dry fuels
exist. Following dry thunderstorms on Day 1/Monday, dry and windy
conditions on Day 2/Tuesday may encourage possible lightning
holdovers to emerge east of the Cascades (south-central OR) into the
northern Sierra Nevada (northeast CA/northwest NV), and west-central
UT where Elevated highlights were maintained. The rest of the
forecast remains on track, see the previous discussion for more
information.
..Elizalde-Garcia.. 07/06/2026
.PREV DISCUSSION... /ISSUED 0206 AM CDT Mon Jul 06 2026/
...Synopsis...
Fire weather concerns will continue to be driven by a combination of
dry thunderstorm potential as well as dry/windy conditions across
portions of the West on Tuesday. A slight eastward shift of the
upper ridge from the Four Corners into the central Rockies is
expected through Tuesday evening. This will establish a more
west/southwest flow regime across the West Coast that will be
favorable for downslope flow off the northern Sierra Nevada and
portions of the Cascades. Additionally, a plume of mid-level
moisture will continue to spread east/northeast from the western
Great Basin towards the Four Corners/central Rockies that will
promote dry thunderstorm potential across a broad area.
...Dry Thunderstorms...
Mid-level moisture spreading eastward over the next 24 hours will
impinge on a plume of steep mid-level lapse rates and dry
boundary-layer conditions currently in place across the Four Corners
and central Rockies. This should promote adequate buoyancy for weak
convection by Tuesday afternoon. PWAT values are currently forecast
to range from 0.75 inches from the northern Great Basin to around
0.5 inch across UT and western CO. Forcing for ascent driven by weak
perturbations within the mean southwesterly flow regime over the
northern Great Basin should decrease eastward into the Four Corners
were orographic ascent will yield more isolated thunderstorms. This
will likely result in a mix of wet and dry thunderstorms across the
northern Great Basin with increasingly dry thunderstorms with
east/southeastward extent. Portions of central OR were removed from
the risk area owing to the potential for wetting rainfall over the
next 24 hours. However, portions of the area may be at risk for dry
lightning if rainfall amounts are more limited than currently
anticipated.
...Cascades into the northern Sierra Nevada...
The establishment of a southwest flow regime across the Cascades and
northern Sierra Nevada will promote strengthening downslope flow
along the eastern slopes. Latest forecast guidance suggests that the
driest and windiest conditions will emerge across northeast
CA/northwest NV where sustained winds between 15-20 mph will likely
coincide with 10-15% RH minimums. Further north, cooler conditions
will result in more sparse coverage of elevated conditions, but
favored gaps will likely see 15-20 mph winds with RH values falling
into the 15-25% range by late afternoon.
...Eastern Nevada into western Utah...
Another day of dry and windy conditions is expected for Tuesday as
weak troughing across the northern Great Basin drives an uptick in
southwesterly flow across the region. Confidence in 10-15% RH
minimums is fairly high given downslope trajectories off the
southern Sierra Nevada over the preceding 24 hours, and latest
HREF/REFS guidance suggests wind speeds will likely reach 15 mph for
many locations, resulting in a few hours of sustained elevated
conditions.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 062201
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0501 PM CDT Mon Jul 06 2026
Valid 081200Z - 141200Z
...Synopsis...
Overall, this week exhibits a critical fire weather pattern for
portions of the Intermountain West with hot, dry and windy
conditions followed by thunderstorms, then dry and breezy conditions
once again later in the week. An upper-level trough will move into
southwest Canada Day 3-4/Wednesday-Thursday, with zonal westerly
flow and a flattened ridge over the northern half to two-thirds of
the West. As the upper-level ridge flattens, the upper high
retrogrades off the southern California coast. A weak dry cold front
will push through the Northwest and into the Great Basin mid-week,
with moisture and above normal temperatures ahead of it. Moisture
will likely push east of the Colorado Rockies and be suppressed
southward to southern Arizona and New Mexico beyond Day 5/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/Saturday - Day 8/Monday.
...Days 3-4/Wednesday-Thursday...
Isolated to scattered mixed wet/dry thunderstorms remain likely
across portions of the northern/eastern Great Basin into the Four
Corners on Day 3/Wednesday. The 10% area was expanded into southern
ID where a mix of wet/dry thunderstorms may overlap pockets of dry
and receptive fuels. A 40% Critical area was maintained for low RH
and gusty conditions in the Washington Cascade Gaps into the
Columbia Basin, while a more expansive 40% Critical was introduced
across much of the Great Basin into northern AZ. Dry and breezy
conditions continue on Day 4/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.
...Day 5-6/Friday-Saturday...
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 were introduced on both days 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.. 07/06/2026
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