


Fire Weather Outlook Discussion
Issued by NWS
Issued by NWS
696 FNUS21 KWNS 010620 FWDDY1 Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 AM CDT Tue Jul 01 2025 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN AND CENTRAL NEVADA... ...Synopsis... An amplified upper trough slowly progressing eastward across central California will be responsible for supporting mixed dry/wet thunderstorms across portions of northern California into southern Oregon, critical fire-weather conditions across portions of southern and central Nevada, and for pushing enough monsoonal moisture into portions of Arizona, Utah, and southeastern Idaho to support lightning over dry fuels. ...Central/Southern Nevada... Deep boundary layer mixing below strong meridional mid-level flow will result in dry and windy conditions that overlap with fuels receptive to wildfire spread (ERCs at or exceeding the 90th annual percentile). Relative humidity of 5-10% coupled with 25 MPH winds, possibly gusting to 30 MPH, are anticipated across portions of central and southern Nevada -- warranting the introduction of Critical highlights. ...Dry Thunderstorms... A mix of wet/dry thunderstorms are anticipated across portions of northern California into southern and eastern Oregon. Thunderstorms are expected to develop within deep inverted-v boundary-layer profiles with total precipitable water content between 0.5 - 0.75 in, and 0 - 6 km mean wind speeds of 15-20 MPH. With ERC percentiles climbing to the 70th-80th annual percentiles, lightning over dry fuels with little wetting precipitation will pose a fire-weather risk. Further east across portions of northern Arizona, western/central Utah, and far southeastern Idaho, a mix of wet and dry thunderstorms is expected. ERC fuel percentiles are more significant across this region, ranging from the 90th annual percentiles to exceeding the 98th annual percentiles across large portions of the region. With total precipitable water vapor content forecast between 0.5 and 0.8 inches resulting in lower precipitation efficiency, dry lightning ignitions will be possible. ..Halbert.. 07/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... $$