Fire Weather Outlook Discussion
Issued by NWS
Issued by NWS
481 FNUS21 KWNS 081638 FWDDY1 Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1137 AM CDT Sat Aug 08 2026 Valid 081700Z - 091200Z Minor adjustments were made to the risk areas based on updated guidance; otherwise, the forecast remains on track. A passing mid-level wave will contribute to the flattening of the upper ridge over the northwestern CONUS, promoting areas of stronger flow aloft. Expansive elevated fire weather conditions are expected as deeper mixing and terrain-enhanced flow promote wind gusts of 25+ mph and RH values of 5-15%. The fuelscape across the Pacific Northwest, Northern Rockies, and northern Plains remains very dry and increasingly receptive, as depicted by numerous wildfires across these regions. Farther south, mixed wet/dry thunderstorms are expected this afternoon along the northern fringe of advecting monsoonal moisture. Satellite imagery portrays lingering cloud cover across portions of the Great Basin and residual smoke in Utah, which may limit some instability. However, prolonged hot, dry, and unstable conditions ahead of the monsoonal surge should result in at least some dry thunderstorm potential where receptive fuels exist. Across the southern High Plains, daytime high temperatures will approach 100+ degrees while sustained south/southwesterly winds increase to 15-20 mph and RH values decline to less than 15%. These meteorological conditions support a region of Elevated highlights, though a mixed fuelscape of live fuels and areas of grass curing (as seen by a 30-day NDVI comparison) and fuels rebounding from spotty recent rainfall yield a complicated environment. Nonetheless, fire concerns remain across the risk area. ..Elizalde-Garcia.. 08/08/2026 .PREV DISCUSSION... /ISSUED 0102 AM CDT Sat Aug 08 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 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. A weak lower-level wave will move east from the central Rockies into the central Plains, bringing with it a belt of modest southwesterly low-level flow. At the same time, monsoonal moisture will continue to advance northward across the West, bringing with it chances of afternoon thunderstorms atop a very dry boundary layer. ... Northern Intermountain West and Pacific Northwest ... Most of the region will see the development of surface winds around 15 mph with higher gusts as diurnal heating and the associated deep vertical mixing bring down modest mid-level flow. The deep mixing will also contribute to relative humidity falling to perhaps as low as 5% in favored areas across the region, with minimum afternoon relative humidity between 10-15% elsewhere. Given very receptive fuels, elevated to locally critical fire weather conditions are likely. ... 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. ... High Plains of southeast Colorado, southwest Kansas, far northeast New Mexico, and the western Oklahoma Panhandle ... Model guidance is in good agreement with a belt of modest southwesterly 700-millibar flow stretching from southeast Colorado toward the Great Lakes. This flow should easily mix down to the surface during the afternoon as strong diurnal heating mixes into and through this layer. The result will be gusty surface winds between 15-20 in the presence of minimum relative humidity falling into the teens. Seasonally adjusted ERC percentiles show a very dry fuelscape, with percentiles between 95-98%. A small elevated area was introduced to cover this potential. ...Please see www.spc.noaa.gov/fire for graphic product... $$