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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 031542
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1042 AM CDT Fri Jul 03 2026
Valid 031700Z - 041200Z
...CRITICAL FIRE WEATHER AREA FOR EASTERN UTAH AND WESTERN/SOUTHERN
COLORADO...
The Elevated/Critical areas were expanded slightly eastward in
portions of southern Colorado. The most recent high-resolution
forecast guidance indicates that westerly downslope winds look to
extend dry and windy conditions slightly farther east than
previously anticipated. Additionally, some mid-level moisture is
moving into/over portions of Colorado, which along with the very dry
and breezy low levels, deep boundary layer mixing, and active large
fires could result in deep pyroconvection. Otherwise the forecast
remains on track, and please see the previous forecast for more
details.
..Nauslar.. 07/03/2026
.PREV DISCUSSION... /ISSUED 1258 AM CDT Fri Jul 03 2026/
...Synopsis...
Another day of elevated to critical fire weather conditions is
expected across the greater Four Corners region. Early-morning
surface observations continue to show a very dry air mass in place
across the region with poor overnight RH recoveries as of 06 UTC.
This dry air mass will remain in place, especially as some degree of
subsidence overspreads AZ/NM in the wake of a low-amplitude
mid-level trough. Consequently, afternoon RH minimums will likely
fall into the single digits to low teens once again today.
The passage of the upper wave, coupled with modest zonal flow over
the central Rockies, will promote lee cyclogenesis across eastern
CO. The resulting mass response will yield a swath of 15-20 mph
winds across the Four Corners region. 7-day meteograms from eastern
UT and western CO depict sustained 15-20 mph winds with frequent
gusts between 20-30 mph in recent days under a similar synoptic
regime. Based on latest ensemble guidance, a repeat of these
conditions appears likely today and warrants maintaining Critical
highlights (especially given ongoing fire activity over the region).
...Dry Thunderstorms...
00 UTC RAOBs from LKN, SLC, and RIW all sampled steep mid-level
lapse rates and some degree of mid-level moisture across the
northern Great Basin. Further ascent/cooling is expected over the
next 12-24 hours as a mid-level wave overspreads the region. The
combination of mid-level cooling/moistening, low-level heating, and
PWAT values between 0.4 to 0.6 inches should result in thermodynamic
profiles favorable for dry thunderstorms. Recent fuel analyses
continue to show ERC values generally below the 80th percentile,
which suggests that fuels may not be overly receptive to lightning
starts. This, along with somewhat slow (10-15 knot) storm motions,
limits confidence in a more substantial dry-lightning threat.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 031929
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Fri Jul 03 2026
Valid 041200Z - 051200Z
...Colorado...
An IsoDryT area was added for portions of central Colorado as
moisture advects westward into the Colorado Rockies. Much of the
moisture will not make it past the Front Range, but deep terrain
circulations and forecast guidance consensus of a weak shortwave
trough/vort max rotating over the area near peak heating should be
enough for isolated thunderstorms. Thunderstorm probabilities are
10-20%, but with any thunderstorm that forms, it will be dry and
over near to record dry fuels. Additionally, any active large fires
in the vicinity of the IsoDryT area will have increased
probabilities of deep pyroconvection.
...Inland Northwest...
Gusty Cascade Gap winds will spread out onto portions of the
Columbia Basin tomorrow. Westerly sustained winds of 10-20 mph with
gusts of 20-30 mph amid minimum RH of 12-25% are forecast tomorrow
across portions of the Inland Northwest. Locally elevated conditions
may develop farther south in portions of central/eastern Oregon as
well.
..Nauslar.. 07/03/2026
.PREV DISCUSSION... /ISSUED 0107 AM CDT Fri Jul 03 2026/
...Synopsis...
Fire weather concerns will remain limited for Saturday compared to
previous days. A building upper-level ridge across the
Southwest/Four Corners will maintain very dry conditions across UT
and CO with another day of single-digit RH minimums likely. However,
this will also act to limit the intensity of the lee cyclone over
the southern/central High Plains and displace it further east across
KS compared to previous days. Consequently, the mass response over
the Four Corners will be weaker, limiting the potential for
sustained elevated/critical wind speeds. While localized elevated
conditions are possible across the greater Four Corners region
(particularly across NM), such conditions will likely be fairly
transient and confined to local terrain features.
...Dry Thunderstorms...
An influx of Pacific moisture is expected across AZ and western NM
through the day Saturday. Steep lapse rates will likely accompany
the leading edge of the returning moisture and may support pockets
of sufficient buoyancy for transient thunderstorms across far
eastern AZ and into western/central NM. While this potential is
noted, confidence is very limited owing to considerable spread among
recent guidance regarding thunderstorm development and coverage.
However, if convection can develop some dry-lightning threat will
likely materialize given antecedent dry boundary-layer conditions.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 032156
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0456 PM CDT Fri Jul 03 2026
Valid 051200Z - 111200Z
Upper-level heights build over the southern/central Intermountain
West this weekend into early next week as an upper high begins to
develop over the Southwest. A weak upper low will track
north-northeast over California into the northern Rockies Day
3/Sunday - Day 4/Monday. Moisture will move northward this weekend
through early next week as south-southwest flow develops over much
of the West. An upper-level trough is forecast to move into the
Northwest around mid-next week, with weak ridging/higher heights
remaining across the southern US.
As moisture increases into the greater Four Corners region,
thunderstorm chances will increase. Given that low-levels will
remain dry west of the Divide, and that PWAT values are likely to
remain below 0.9" on the northern portions of this moisture plume,
isolated to scattered mixed wet/dry thunderstorms are likely to
develop. Forecast guidance currently favor portions of northern
Arizona, central/eastern Utah, and western Colorado for drier
thunderstorm development early next week. These outlook areas also
have very to record dry fuels. The 10% DryT areas may shift and
potentially expand, including into eastern Nevada, as forecast
guidance coalesces. While mixed wet/dry thunderstorms are likely
across portions of New Mexico, central Colorado, and southeast
Arizona, consecutive days of thunderstorm development will likely
reduce the risk of new ignitions.
Isolated to scattered mixed wet/dry thunderstorms are possible
across portions of northern California into southeast Oregon on Day
3/Sunday into Day 4/Monday. This may include nocturnal thunderstorms
during Day 3/Sunday night. PSA Fire Danger charts indicate ERCs are
below average for this time of year and below the 90th percentile.
Given the uncertainty of thunderstorm development and fuel
receptiveness, no DryT probabilities were included.
As upper-level troughing moves into the Northwest next week, gusty
Cascade Gap winds are likely to develop with dry/breezy conditions
spilling into the Columbia Basin. However, the timing and magnitude
of these conditions remain uncertain, and this will continued to be
monitored in subsequent outlooks.
..Nauslar.. 07/03/2026
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