031 FXUS65 KVEF 200527 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 1027 PM PDT Thu Jun 19 2025 .KEY MESSAGES... * Extreme Heat Warning remains in effect today with afternoon highs 6 to 10 degrees above seasonal normals. * Elevated wildfire concerns expected through Saturday due to gusty winds and single-digit afternoon relative humidities. * Temperatures drop this weekend as south-southwest wind gusts increase across the region. Temperatures slowly rebound next week with light afternoon breezes. && .UPDATE...Huge smoke plume from fire(s) in Baja California was evident on visible satellite imagery racing northeast through eastern San Bernardino County into southern Clark County. Updated weather grids with new HRRR Smoke output, which gave haze for areas well southeast of I-15 through Saturday. && .DISCUSSION...Today through Thursday. Extreme Heat Warning remains in effect for lower elevations of southeastern California, southern Nevada, and northwestern Arizona as a result of a strong ridge of high pressure centered over northern Mexico. Widespread "Moderate" HeatRisk this afternoon, with "Major" HeatRisk in the desert valleys. A strong area of low pressure off the coast of the Pacific Northwest will drop southward into the Great Basin over the next couple of days. The associated trough will drop through the western CONUS, working to tighten pressure gradients over the Desert Southwest as the aforementioned ridge shifts eastward. Gusty south-southwest winds will pick up each afternoon heading into the weekend and will peak on Saturday (15-25 mph with gusts 25-35 mph) as the trough axis pushes through our forecast area. These wind speeds, combined with above-normal temperatures and single-digit afternoon relative humidities, will increase wildfire danger across southern Nevada and northwestern Arizona. As such, Red Flag Warnings have been issued through Saturday, with more details in the FIRE WEATHER discussion below. In addition to fire concerns, a Wind Advisory has been issued for western San Bernardino County for Friday and Saturday, a Wind Advisory has been issued for Mohave County for Saturday, and a Lake Wind Advisory has been issued for the Lake Mead National Recreation Area including Lake Mohave for Saturday due to wind gusts between 35 and 45 mph and wave heights in excess of 2 feet. Heights will drop across the region as the trough axis pushes through the Desert Southwest and shoves the northern Mexico high pressure eastward. Temperatures will drop to below-normal over the weekend as a result. Through the week, heights will slowly rise despite weak troughing in place, which will allow temperatures to gradually increase heading into next weekend. && .FIRE WEATHER...A Red Flag Warning is in effect through this evening for Fire Weather Zone NV-460. A Red Flag Warning is in effect through Friday evening for south-central Nevada (Zones 461, 462, 463, and 464). A Red Flag Warning is in effect through Saturday evening for southern Nevada (Zones 465, 466) and northwestern Arizona (Zones 101, 102). Expect south-southwesterly winds between 20 and 25 mph with gusts between 30 and 40 mph each afternoon. Increased risk of wildfire starts and spreads as a result of these wind speeds coupled with single-digit afternoon relative humidities and overnight recoveries between 15 and 25 percent. Temperatures will drop below-normal Saturday and Sunday and wind speeds will drop Sunday onward, which will mitigate wildfire risk. Outdoor burning as well as recreation involving sparks or flames is not recommended. && .AVIATION...For Harry Reid...For the 06Z Forecast Package...South winds will continue through the night, sometimes gusting 20 to 25 knots and sometimes lulling to 10 knots. Winds will increase again around midday Friday, with gusts of 25 to 30 knots. No clouds or weather through the TAF period, although smoke aloft from a distant fire could occasionally invade the sky. Temperature rising to 100F around 19-20Z Friday. For the rest of southern Nevada, northwest Arizona and southeast California...For the 06Z Forecast Package...Gusty south to southwest winds will continue through Friday, with the strongest gusts of 30 to 40 knots near and north of Barstow as well as over mountain ranges. Smoke aloft from a distant fire will cover portions of the sky southeast of Interstate 15. Otherwise, no operationally significant clouds or weather through the TAF period. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ UPDATE...Morgan DISCUSSION...Soulat AVIATION...Morgan For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter