483 FXUS65 KVEF 162314 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 414 PM PDT Mon Jun 16 2025 .KEY MESSAGES... * A Red Flag Warning remains in effect until 8 PM across portions of southern Nevada and northwestern Arizona. Winds are expected to decrease this evening. * Heat will increase Wednesday and Thursday. An Extreme Heat Warning has been issued for portions of southeast California, southern Nevada, and northwest Arizona. * Relief from the heat is expected beginning Friday and especially over the weekend, but increasing winds beginning Thursday could bring another round of high fire danger. && .DISCUSSION...through next Monday. Midday satellite loop showed a few flat cumulus and lenticular clouds over the southern Great Basin, with clear skies over the Mojave Desert. Surface obs showed southwest winds gusting 20 to 30 mph, temperatures a few degrees higher than 24 hours ago, and an interesting patchwork of dewpoints near or below 0F mixed in among dewpoints in the 30s and 40s, which was most likely related to extremely dry air aloft being mixed down in the lee of mountain ranges. On water vapor satellite imagery, mid level troughing was seen moving into the West Coast. This will traverse our area overnight, keeping winds elevated, although gusts will be less strong than today. Behind this trough, high pressure will strengthen, with 500 mb heights peaking over our area on Wednesday. For Wednesday, HeatRisk values have increased and the coverage of Major HeatRisk has expanded since yesterday. HeatRisk is a bit less expansive on Thursday, but our area could have the perfect blend of still-high heights and increasing wind/deepening mixed layer to result in another very hot day. Thus, it is anticipated that HeatRisk will increase for Thursday as well. With this in mind, hoisted an Extreme Heat Warning covering Death Valley National Park, the northern half of San Bernardino County, western and central Clark County, central and southern Mohave County, and the Colorado River Valley. Fortunately, this will be a short-lived episode, as the aforementioned wind on Thursday is on the leading edge of an unseasonably deep trough in the Gulf of Alaska. As this trough moves into the Pacific Northwest and Intermountain West Friday through Sunday, heights over our area will crash, and high temperatures will drop approximately 10 to 15 degrees from Thursday to Sunday. However, this relief will come at a price, as stronger winds and low humidity will cause fire weather concerns Thursday through Saturday before winds finally abate Sunday. Temperatures should start to rebound on Monday. && .AVIATION...For Harry Reid...For the 00Z Forecast Package...VFR conditions will prevail through the TAF period. 15 to 25 knot southwesterly wind gusts will continue into the overnight period, dropping off early Tuesday morning. Temperatures will remain above 100 degrees through around 03/04Z this evening. High temperatures on Tuesday will top out around 106 degrees with temperatures over 100 from 19Z to 04Z For the rest of southern Nevada, northwest Arizona and southeast California...For the 00Z Forecast Package...VFR conditions will prevail through the 06Z TAF period with FEW clouds AOA 20 kft drifting across the southern Great Basin. Breezy southerly-to- westerly winds will continue into the evening hours with wind gusts in the 20 to 35 knot knot range. Winds will gradually decrease during the overnight period with lighter winds expected tomorrow. && .FIRE WEATHER...A Red Flag Warning remains in effect until 8 PM today across southern Nevada (Zones 462, 464, 465, 466) and northwestern Arizona (Zones 101, 102). Winds should begin to decrease around 8 PM, lessening the threat. Another period of strong winds and low humidity is likely to occur Thursday through Saturday, and fire weather headlines may be needed again. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION/FIRE WEATHER...Morgan AVIATION...Stessman For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter