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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 071640
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1140 AM CDT Fri Aug 07 2026
Valid 071700Z - 081200Z
The forecast remains on track for elevated fire weather conditions
across much of the northwestern CONUS, and isolated dry
thunderstorms in southern Nevada and southwest Utah. Satellite
imagery portrays a dense layer of wildfire smoke over much of the
Intermountain West, which may limit daytime high temperatures by a
few degrees across the Elevated risk area. Vertical mixing and
strengthening upper-level flow will contribute to gusty surface
winds and critically low RH values this afternoon amid an
exceptionally dry fuelscape (ERCs exceeding the 95-98th percentile),
generating yet another day of heightened fire concerns. Surface
winds of 15 mph or greater and RH values of 5-15% will further
exacerbate numerous large fires across the Pacific Northwest and
northern Rockies, alongside any new starts. See the previous
discussion for more information.
..Elizalde-Garcia.. 08/07/2026
.PREV DISCUSSION... /ISSUED 0218 AM CDT Fri Aug 07 2026/
...Synopsis...
A large mid-level ridge will remain centered near the Four Corners
region of the US today, with the strongest mid-level flow across the
CONUS found along the US-Canadian border. Monsoonal moisture will
continue to infiltrate portions of southern California, Nevada, and
Utah, bringing with it chances of afternoon thunderstorms atop a dry
boundary layer.
... Northern Intermountain West ...
Modest westerly mid-level flow will be found across the region
today. As diurnal heating contributes to deep vertical mixing,
surface winds around 15 mph with stronger gusts are likely.
Additionally, the deep mixing will contribute to relative humidity
falling to perhaps as low as 5% across favored areas across the
region, with minimum afternoon relative humidity between 10-15%
elsewhere. Given very receptive fuels across the area, elevated to
locally critical fire weather conditions are likely.
... Southern Nevada and Southwest Utah ...
Thunderstorms are expected along the western periphery of a
mid-level ridge where the advancing monsoonal moisture will be
found. The northern edge of the monsoonal moisture will likely be
constrained to the mid and upper levels initially, leaving a very
dry sub-cloud layer in place. High-based thunderstorms that do
develop here will likely feature significant evaporation of falling
precipitation leading to little, if any, appreciable rainfall.
Additionally, evaporative cooling beneath the cloud layer will
result in gusty/erratic thunderstorm outflows.
... California ...
Localized fire weather concerns will be possible across portions of
California, particularly the interior portions of Southern
California. Here, hot temperatures into the 110Fs will contribute to
relative humidity into the single digits. However, relatively calm
winds should limit the overall elevated fire weather conditions to a
more localized nature.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 071906
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0206 PM CDT Fri Aug 07 2026
Valid 081200Z - 091200Z
Only minor adjustments were made to the risk areas based on recent
guidance. Otherwise, the forecast remains on track for expansive
elevated fire weather conditions across the northwestern CONUS, and
dry thunderstorms in the Sierra Nevada and Great Basin. See the
previous discussion for more information.
..Elizalde-Garcia.. 08/07/2026
.PREV DISCUSSION... /ISSUED 0218 AM CDT Fri Aug 07 2026/
...Synopsis...
A large mid-level ridge will remain centered near the Four Corners
region of the US on Saturday, with the strongest mid-level flow
across the CONUS once again found along the US-Canadian border. A
weak mid-level vorticity maximum will move across the Pacific
Northwest, however mid-level flow enhancement looks modest with this
feature. At the same time, monsoonal moisture will continue to
advance northward across the West, bringing with it chances of
afternoon thunderstorms atop a dry boundary layer.
... Northern Intermountain West and Pacific Northwest ...
Modest westerly mid-level flow will be found across the region
Saturday, especially closer to the Canadian border. Another
potential area of enhanced mid-level flow could develop across
northern Oregon and much of Washington in association with a passing
mid-level vorticity maximum.
Common across most of the region will be the development of surface
winds around 15 mph with higher gusts as diurnal heating and the
associated deep vertical mixing bring down some of that enhanced
mid-level flow. The deep mixing will also contribute to relative
humidity falling to perhaps as low as 5% across favored areas across
the region, with minimum afternoon relative humidity between 10-15%
elsewhere. Given very receptive fuels across the area, elevated to
locally critical fire weather conditions are likely.
One potential area for a possible upgrade will be across portions of
the Pacific Northwest as the mid-level vorticity maximum moves
across the area. Despite significant smoke plumes potentially
limiting vertical mixing, terrain favored areas such as mountain
gaps in the Cascades and within eastern portions of the Columbia
River gorge, may see periods of higher sustained winds, leading to a
window of potentially critical conditions. Confidence is increasing
in this scenario, but still remains too low to highlight at this
lead time.
... California Sierras, Southern/Central Nevada, and much of Utah
...
Similar to Friday, thunderstorms are expected along the western
periphery of a mid-level ridge where the advancing mid- and
upper-level monsoonal moisture will be found. Beneath this moist
plume, a very dry sub-cloud layer will support significant
evaporation of falling precipitation leading to little, if any,
appreciable rainfall. Evaporative cooling beneath these dry
thunderstorms will result in gusty/erratic thunderstorm outflows.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 072215
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0515 PM CDT Fri Aug 07 2026
Valid 091200Z - 151200Z
...Synopsis...
A mid-level shortwave will move into the northern High Plains by Day
3/Sunday within a deamplifying upper ridge. This will leave a zonal
flow pattern in place across the northern CONUS for early next week
with lingering fire weather concerns over portions of the
Intermountain West. A dry thunderstorm threat will likely persist
across portions of the Great Basin and central Rockies on Days
3-4/Sunday-Monday on the northern fringe of deeper monsoonal
moisture across the Desert Southwest.
...Days 3-4/Sunday-Monday...
...Northern Intermountain West and adjacent northern High Plains...
A mid-level short wave should round the flattening upper ridge over
the West, affecting the Northern Rockies on Day 3/Sunday. A
tightening surface pressure gradient along the southern Cascades and
adjacent terrain will promote gusty surface winds within a dry
boundary layer. Breezy west winds up to 15 mph (locally 20 mph) and
low relative humidity will combine with increasingly receptive fuels
across the broader northwestern CONUS. As such, 40% Critical
probabilities were largely maintained for this broad region. On Day
4/Monday, stronger upper-level flow will continue across the
flattened ridge, sustaining a pattern of dry and breezy conditions
atop exceptionally dry fuels. 40% Critical probabilities have been
expanded to account for a broader, prolonged fire weather threat.
...Southern Sierra, central Nevada and portions of Utah...
High based convection is likely to evolve Days 3-4/Sunday-Monday on
the northern periphery of deeper monsoonal moisture. PWATs ranging
of 0.60-0.80" and daytime instability will likely lead to isolated
high-based thunderstorms across portions of the southern Sierra
Nevada, upper Great Basin, and northwestern CO on Day 3/Sunday. This
threat will persist across the northern Great Basin, southwestern
WY, and northwestern CO on Day 4/Monday. Uncertainty remains in the
strength and residence time of the monsoon surge, though a mix of
wet/dry thunderstorms atop a drought-stressed and significantly dry
fuel environment raises concerns for lightning-induced ignitions; as
a result, 10% Dry Thunderstorm probabilities have been expanded on
Day 3/Sunday and introduced on Day 4/Monday.
...Days 5-8...
On Day 5/Tuesday, 40% Critical probabilities were expanded across
southeastern OR, northeastern CA, and portions of the Great Basin
where forecast confidence is higher in a continuation of dry and
breezy conditions. Extended ensemble guidance depicts a pattern
change across the western CONUS late next week, with offshore
troughing bringing the potential for surging monsoonal moisture and
thunderstorms to northern California and the Pacific Northwest.
However, predictability is too low in the long term to introduce any
probabilities at this time.
..Elizalde-Garcia.. 08/07/2026
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