309
FNUS21 KWNS 101630
FWDDY1

Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1129 AM CDT Mon Aug 10 2026

Valid 101700Z - 111200Z

The ongoing forecast remains on track for elevated fire weather
conditions across the California Central Valley and portions of the
Intermountain West, and isolated dry thunderstorms in the Great
Basin, northwestern Colorado, and the Wyoming higher terrain.
Surface observations depict more improved overnight recoveries
occurred across southern Utah and eastern Nevada, resulting from
surging monsoonal moisture and greater coverage of observed 0.1-0.4"
rainfall in the last 24 hours. Farther north/east, a mix of dry
thunderstorms remain likely where a dry boundary layer will favor
evaporation and less precipitation efficiency. Wildfires and any new
starts may be exacerbated by meteorological conditions, especially
in areas where breezy winds/low RH and the isolated dry thunderstorm
risk overlap. Deep pyroconvection is also possible on active large
wildfires due to the favorable dry thunderstorm environment, as
shown by the Rocky Canyon fire producing a pyroCb yesterday
afternoon. Please see the previous discussion for more information.

..Elizalde-Garcia.. 08/10/2026

.PREV DISCUSSION... /ISSUED 0134 AM CDT Mon Aug 10 2026/

...Synopsis...
Fire weather concerns will persist today across parts of the western
CONUS. Early morning water-vapor imagery continues to depict a broad
upper ridge over the Southwest, and this feature is expected to
remain in place through at least the next 48 hours. As a result,
low-level mass responses will be muted with generally weak gradient
winds for most locations west of the Rockies. Nonetheless, some
areas will still experience terrain-driven wind speeds reaching or
exceeding Elevated thresholds with a very dry air mass.
Additionally, monsoonal moisture continues to spread northward
through the Great Basin and Four Corners region, and will support
another day of isolated dry thunderstorms.

...Great Basin...
Breezy conditions (sustained winds around 15 mph) with RH minimums
in the teens and low 20s are expected across a broad swath of the
northern Great Basin again today, largely heating and deep mixing of
a dry low-level air mass in place across the region. A few regions
will likely see more prolonged and somewhat widespread elevated
conditions with sustained winds closer to 20 mph where topographic
influences will locally augment low-level flow (namely in the lee of
the northern Sierra Nevada in northwest NV and through the Snake
River Valley in eastern ID). Fuels across the broader region remain
receptive to fire starts (as evident by scattered new starts over
the past 24 hours), and will support another day of fire weather
concerns.

...California Central Valley...
An onshore flow regime will persist for today along the CA coast,
which should favor downslope flow into western portions of the
Central Valley. Dry conditions should prevail again today with
afternoon RH values in the teens to low 20s. Elevated fire weather
conditions are possible where breezy downslope winds can overlap
with dry conditions.

...Southern High Plains...
Modest lee troughing will remain in place along the High Plains for
today, which will maintain south to southwesterly low-level winds
across the OK/TX Panhandles and adjacent portions of southwest KS
and northwest OK. Based on recent ensemble guidance and observed
winds yesterday (which featured a similar synoptic regime),
sustained winds between 15-20 mph are likely with gusts up to 30-40
mph possible. Additionally, forecast high temperatures are expected
to once again exceed 100 F with afternoon RH values in the teens to
low 20s. These hot, dry, and windy conditions should support a swath
of elevated to locally critical fire weather conditions.

...Dry Thunderstorms...
00 UTC RAOBs from across the Great Basin and Four Corners region
sampled very steep mid-level lapse rates within a plume of rich
monsoonal moisture. PWAT values of 0.8 to 1.0 inch were noted across
much of the region and will promote a mix of wet and dry
thunderstorms for most of AZ, UT, and NV. However, drier conditions
are noted on the northern fringe of the moisture plume and should
support a higher probability for predominantly dry thunderstorms
this afternoon and evening - mainly across northern NV into portions
of ID and WY. Given a receptive fuel landscape already in place,
lightning ignitions will be a concern.

...Please see www.spc.noaa.gov/fire for graphic product...

$$