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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 051541
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1041 AM CDT Sun Jul 05 2026
Valid 051700Z - 061200Z
Both IsoDryT areas were adjusted based on the latest observations
and forecast guidance. The IsoDryT area was expanded south and east
along the Sierra and into central Nevada. Sufficient moisture and
forcing for ascent aloft associated with the mid-level shortwave
trough should produce isolated thunderstorms with aid from
terrain-induced circulations. Mid/high clouds may inhibit solar
insolation and thus terrain induced upslope flow, but enough
instability and buoyancy should develop to support isolated
thunderstorms. Additionally, thunderstorms are likely to continue
into the evening and possibly overnight with northern portions of
the IsoDryT area favored.
The other IsoDryT area was expanded slightly northwest along the
Mogollon Rim and shifted east across northwest New Mexico through
southern/central Colorado along the western edge of expected wetter
thunderstorms. Sufficient moisture is unlikely to make it into far
northwest New Mexico and western Colorado and subsidence aloft
indicate little to very low probabilities (<10%) of thunderstorms
developing across the areas that were removed. However, the
potential for deep pyroconvection remains in the vicinity of the
IsoDryT area on active large wildfires as the Willow Fire produced
at least one pyroCb pulse yesterday afternoon in a similar
environment.
..Nauslar.. 07/05/2026
.PREV DISCUSSION... /ISSUED 0108 AM CDT Sun Jul 05 2026/
...Synopsis...
Dry thunderstorms will pose a fire weather risk today across
portions of the Pacific Northwest and Southwest. Recent upper-air
analyses show steady amplification of an upper ridge over the
greater Four Corners region. This will maintain very dry and warm
conditions for much of the western CONUS, but should generally limit
surface pressure gradient winds. However, very dry low-level
conditions coupled with an influx of mid-level moisture will support
thermodynamic profiles favorable for dry thunderstorms across
portions of the West.
...Northern California into Oregon and Nevada...
A shortwave trough embedded within the mean south/southwesterly
upper-level flow is noted in water-vapor imagery along the CA coast.
This feature will continue to move northeast towards southern OR
through today. A modest influx of mid-level moisture attendant to
the wave coupled with weak ascent should support adequate buoyancy
for thunderstorms from northern CA into OR and adjacent portions of
northwest NV/southwest ID. Very dry boundary-layer conditions noted
in 00 UTC soundings should modulate rainfall amounts and favor dry
thunderstorms. Confidence in dry lightning potential is greatest
across southern OR where recent fuel reports suggest fuels are
becoming increasingly receptive and lightning ignitions will be
possible.
...Southwest...
Early-morning GOES PWAT estimates depicts a plume of 0.75-1.25 inch
PWAT values advecting northward from Baja California. The eastern
fringe of this moist plume will spread across AZ and far western NM
through the day where lapse rates remain very steep from the surface
through around 6 km based on regional 00 UTC soundings. Model
guidance continues to suggest that mid-level moistening will be
sufficient to support enough buoyancy for high-based convection by
late afternoon. With LCL heights forecast to be around 3 km,
thermodynamic profiles will be favorable for dry lightning strikes
from eastern AZ into NM and south-central CO. Confidence in dry
thunderstorm potential remains highest across eastern AZ into
southwest NM, but recent CAM ensemble guidance has trended towards
higher probabilities for convection across southern CO to the west
of the Front Range where conditions remain very dry and active fires
have been ongoing. Some guidance hints that very isolated
thunderstorms are possible as far west as central AZ along the
Mogollon Rim, but ensemble support remains too limited to warrant a
westward expansion.
...Southern Montana...
Additional dry thunderstorms appear possible across southern to
southwest Montana this afternoon as weak upper perturbations crest
the apex of the upper ridge. Despite a fairly strong convective
signal in latest ensemble guidance and forecast soundings depicting
dry boundary-layer conditions, recent rainfall should limit fuel
status for the time being.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 051845
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0145 PM CDT Sun Jul 05 2026
Valid 061200Z - 071200Z
Overall, the forecast remains on track with relatively minor changes
made to the IsoDryT and Elevated areas. A Scattered DryT area was
considered for portions of south-central to southeast Oregon and in
northeast Nevada/vicinity, but there remains enough uncertainty
regarding the overlap of sufficient scattered (40%+) coverage,
rainfall amounts, and receptive fuels to preclude a Scattered DryT
area. Gusty outflow winds are likely with the high-based drier
thunderstorms with forecast DCAPE values of 1000-1600 J/kg across
much of the IsoDryT area, while deep pyroconvection is likely on
active large wildfires.
The Elevated area was expanded based on the latest high-resolution
forecast guidance of dry and breezy conditions across the southern
Great Basin and northwest Arizona. Locally elevated winds/RH are
likely across southern Nevada, northern Arizona, and eastern Utah
into western Colorado surrounding the Elevated area.
..Nauslar.. 07/05/2026
.PREV DISCUSSION... /ISSUED 0144 AM CDT Sun Jul 05 2026/
...Synopsis...
Fire weather concerns will continue across parts of the Southwest,
Great Basin, and Pacific Northwest on Monday - largely driven by dry
thunderstorm concerns.
...Pacific Northwest into the Four Corners...
Short-range guidance continues to show persistent upper ridging over
the Four Corners into the early week. Continued north/northeastward
advection of mid-level moisture into a plume of steep mid-level
lapse rates will result in a broad fetch from the Pacific Northwest
into the Four Corners with adequate buoyancy for weak convection,
PWAT values between 0.5 to 0.75 inches, and very dry boundary-layer
conditions. Confidence in thunderstorm occurrence remains highest
across northern CA/NV into adjacent portions of OR and ID where a
slow-moving shortwave trough will focus ascent. More isolated
thunderstorms will be possible with southeastward extent into the
Four Corners region and will likely be driven primarily by localized
orographic ascent. Across both regions, thermodynamic profiles will
largely favor dry lightning, but 10-15 knot storm motions may allow
for pockets of wetting rainfall. Regardless, receptive fuels will
support some concern for lightning ignitions - especially across the
Four Corners where conditions remain very dry.
...Southeast Nevada into Utah and Arizona...
The development of a weak surface low over the northern Great Basin
will likely support a swath of sustained winds near 15 mph from
southern NV into central UT and northern AZ. With a dry air mass
already in place and little to no low-level moisture recovery
expected, RH minimums will likely fall into the teens Monday
afternoon. Although variance among deterministic solutions remains
somewhat high regarding the coverage of 15 mph winds, recent
high-res ensemble guidance suggests a corridor of sustained elevated
conditions may emerge from southeast NV into adjacent portions of UT
and AZ.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 052148
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0448 PM CDT Sun Jul 05 2026
Valid 071200Z - 131200Z
Overall, this upcoming week represents a critical fire weather
pattern for portions of the Intermountain West with hotter and drier
conditions followed by lightning then dry and breezy conditions. An
upper-level trough will move into southwest Canada mid-week, 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 eventually push east of the Colorado Rockies
and be suppressed southward to southern Arizona and New Mexico mid
to late week. 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/Friday - Day
8/Sunday.
Southwest flow aloft with a ribbon of higher PWAT values (0.5-0.9")
will exist from central Oregon into the Four Corners. Isolated to
scattered mixed wet/dry thunderstorms are likely to develop around
the Greater Four Corners over the higher terrain, with further
development likely extending northwest into central Oregon on Day
3/Tuesday. Wetter thunderstorms are possible in portions of
northeast Arizona and northwest New Mexico. Additionally, there is
some concern with slight height rises, but sufficient moisture,
terrain aided updrafts, and sufficiently steep mid-level lapse rates
should compensate.
Dry and breezy conditions are likely through the Cascade Gaps and
onto the Columbia Basin on Day 3/Tuesday as the onshore pressure
gradient strengthens. The dry and breezy conditions will likely
extend into northeast California and northwest Nevada, but portions
of central/southern Oregon may not hit elevated criteria.
Isolated to scattered mixed wet/dry thunderstorms remain likely
across portions of the northern/eastern Great Basin into the Four
Corners on Day 4/Wednesday. The 10% area was drawn on the
southern/western edge of expected wetter thunderstorms and over more
receptive fuels. Dry and breezy conditions will be likely in the
Washington Cascade Gaps onto the Columbia Basin and in portions of
the central/southern Great Basin ahead of and perhaps behind the dry
cold front and along thermal trough axes where two 40% areas were
introduced. The front and trough axes may also help focus
thunderstorm development.
Dry and breezy conditions continue on Day 5/Thursday across the
southern Great Basin into the Four Corners. Dry and breezy
conditions may be more expansive than currently identified with the
40% area. Some forecast uncertainty exists regarding the upper-level
trough moving into southwest Canada and its interaction with the
upper-level ridge over the Southwest on Day 4/Wednesday - Day
5/Thursday. Moisture is likely to push east and south, with
thunderstorms unlikely west of the Divide on Day 5/Thursday - Day
6/Friday.
..Nauslar.. 07/05/2026
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