666
FNUS21 KWNS 211531
FWDDY1

Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1030 AM CDT Tue Jul 21 2026

Valid 211700Z - 221200Z

Minor modifications were made to the IsoDryT area based on the
latest observations and forecast guidance. Portions of the IsoDryT
area may see more high-based showers with little to no lightning,
while a mix of wet/dry storms remains expected. Additionally, a few
storms may linger overnight in Oregon. Otherwise, the forecast is on
track, and please see the previous discussion for more details.

..Nauslar.. 07/21/2026

.PREV DISCUSSION... /ISSUED 1245 AM CDT Tue Jul 21 2026/

...Synopsis...
...Northern California and west/central Oregon...
Along the northwestern periphery of a large-scale ridge encompassing
much of the central and western CONUS, ample mid-level moisture will
be in place atop a warm and dry airmass across parts of northern CA
into OR. Forecast soundings depict inverted-V profiles with weak
(albeit sufficient) buoyancy for high-based thunderstorms across the
area during the afternoon and evening hours. Cloud cover, smoke, and
warmer temperatures aloft will help limit thunderstorm
development/coverage across the IsoDryT area, but isolated
thunderstorms remain possible. While 0.8 to 1.2 inch PWATs may
promote a mix of wet/dry storms, relatively fast storm motions and
the dry boundary layer should limit precipitation efficiency. As a
result, isolated lightning-induced ignitions will be possible within
a very dry fuelscape.

...South Carolina...
Progressive upper-level troughing will continue across the
northeastern U.S. as a closed low traverses northern Ontario,
sending a cold front through the Ohio Valley. Enhanced 850 mb
southwesterly flow ahead of the front will encourage gusty surface
winds amid minimum RH values of 30-40% in portions of South
Carolina. Locally elevated fire weather conditions are likely, as
ERCs generally range from the 80th-95th percentile across this area.

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

$$