FXUS65 KREV 081900 AFDREV Area Forecast Discussion National Weather Service Reno NV 1200 PM PDT Sun Jun 8 2025 .KEY MESSAGES... * Scattered thunderstorms are expected this afternoon and evening across the Sierra, western Nevada, and northeast California. Activity could possibly continue into the overnight hours. * Above-normal temperatures in the 80s and 90s will persist through midweek, with moderate HeatRisk and mild overnight lows due to lingering cloud cover. * Light winds give way to stronger westerlies midweek, increasing the potential for localized elevated to critical fire weather conditions with low humidity and poor overnight recoveries. && .DISCUSSION... Storm Chances Today: * Thunderstorm activity increases this afternoon and evening, with a 20-40% chance of storms extending from the Sierra into western Nevada and northeast California. A weak area of low pressure approaching the West Coast is helping to enhance moisture and instability along a lee-side trough stretching from the Sierra into west-central Nevada. Storm development will initially focus over the higher terrain before drifting into valleys, especially across Mineral and southern Lyon counties. Additional activity is possible north of US-50 as outflow boundaries spread into western Nevada. A well-mixed sub-cloud layer could support gusty outflow winds up to 50 mph, with localized blowing dust, lightning, small hail, and brief heavy rainfall. Storms may linger into the evening and taper off around midnight. Feels like Summer this Week: * Temperatures will continue to run above normal, with widespread 90+ highs in the valleys and 80s in the Sierra through midweek. Moderate HeatRisk is expected across much of the lower elevations. Overnight lows will remain mild, especially under areas of cloud cover, contributing to limited overnight relief from the heat. Increased Fire Weather Concerns: * Light winds will persist through Monday outside of thunderstorm outflows. However, a shift toward stronger westerly winds is expected by midweek as dry southwesterly flow sets in. This pattern will bring increasing potential for localized elevated- to-critical fire weather conditions, particularly across western Nevada. Afternoon relative humidity values will fall below 15% mid-to-late week, with poor overnight recoveries - raising the risk of new fire starts or the reactivation of holdover fires. For more information see the Fire Weather discussion below. -Johnston && .AVIATION... * Thunderstorms will be the main hazard today, especially for KMMH, KTRK, and KTVL where storm chances range from 20-40% during the 20-03Z window. Other terminals in the region may see a 10-30% chance. Expect variable gusty winds with gusts exceeding 30 kts, mountain obscurations due to CBs and rainfall, small hail, and lightning in and near cells. Continued hot temperatures through midweek may also cause density altitude concerns until a cooldown arrives later in the week. This cool down will bring with it increased southwesterly to westerly winds, which may generate low-level turbulence Wednesday through Friday. -Johnston && .FIRE WEATHER... * Scattered thunderstorms today and Monday will bring a chance for new fire starts due to lightning and gusty outflows, especially across the Sierra Front and western Nevada. Outflow boundaries may trigger additional storms into the evening, with some storms lingering into the early morning hours Monday. Fuels status across much of western Nevada and Mono County remain marginal, and while most storms will produce wetting rains, isolated ignitions and hold overs are possible. * Temperatures will run 10-15 degrees above average through midweek, with highs in the 90s for valleys and 80s in the Sierra, along with mild overnight lows. Afternoon relative humidity values will fall below 15% across the Basin and Range of western Nevada beginning Tuesday. * By Wednesday, southwest to westerly winds combined with very low relative humidity and poor overnight recoveries, will lead to localized elevated to critical fire weather conditions into Saturday, especially across western Nevada. Any holdover fires and new ignitions may spread rapidly under this pattern, particularly in wind-prone areas. -Johnston && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$