Alta Sierra At Shirley Meadows Snow Report

128 FXUS65 KVEF 220650 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 1145 PM PDT Mon Sep 21 2026 .KEY MESSAGES... * Showers and thunderstorms continue late tonight into early Monday morning * Near normal temperatures early this week, warming back up to above normal mid week into next weekend. * Potential increase in moisture for Mohave County and CRV late week && .DISCUSSION...Through Early Next Week. Showers and thunderstorms are ongoing tonight across much of the lower Great Basin and even around the Las Vegas Metro and Mohave County. Satellite imagery shows the upper level low, responsible for all the convection, over Inyo county slowly tracking northeast into Central Nevada. Moisture advection ahead of this system was a bit stronger than initially forecasted while the overall low and associated energy tracked over a 100 miles south and east than what guidance suggested last night. Therefore, widespread thunderstorm activity tonight has been ongoing for much of Southern Nevada and now extending into portions of NW Arizona. Conditions remain favorable for ongoing convection into the overnight hours as the region remains in an area of strong upper level diffluence ahead of the upper trough. Latest LAS ACARs sounding still shows upwards of 700 j/kg of MUCAPE, 1100 j/kg DCAPE, and steep mid and upper level lapse rates supporting continued convective development and the threat for strong winds 50+ mph. Effective bulk shear locally is over 50 kt as a jet streak remains overhead and storm motion is largely parallel to the southerly shear vector resulting in training thunderstorms moving over the same areas. The higher terrain in Southern Nevada has been the focal point for renewed convection late this evening due strong orographic lifting, keeping the majority of the strongest storms in the Spring Mountains, Sheep Mountains, and other surrounding higher terrain. Training storms can be seen over most of the higher terrain around the Las Vegas Valley, while the lower elevation remain quite a bit drier. However, strong outflow from the west, north, and east has allowed for continued northerly wind gusts of 35-55 mph throughout Las Vegas Metro and Southern Nevada this evening. Expect these stronger winds to persist through at least 2-3am until storms begin to wane and shift north and east. Heavy rain in the mountains will gradually decrease through the overnight hours with lighter rain persisting into Central Nevada as the upper low remains in the vicinity. As the low tracks northeast on Tuesday expect a clearing trend across the region as the best forcing for ascent shifts northeast as well. A few showers may develop in far northern Lincoln county but overall the rest of the Southern Great Basin and Mojave Desert should dry out. Slightly cooler air will be in place behind the upper low and most locations will see 2 to 3 degrees of cooling in comparison to todays highs. Generally, dry southwesterly flow and subtle ridging sets up for the remainder of the week and into next week. Medium to long range guidance is in agreement that low level temperatures will run several degrees above normal in this upcoming pattern, resulting in a warming trend each day mid week through the weekend. High temperatures by Saturday may reach the upper 90s to low 100s again in desert valleys. Overall Heat Risk through the week remains low, with sporadic areas of moderate. Guidance continues to hint towards a modest uptick in moisture Thursday and Friday for Southern Nevada, the CRV, and Mohave County. As a ridge builds over the South and Southeast and a lingering trough remains off the coast of California, a strong baroclinic zone sets up over West Texas and into the Four Corners region. While the strongest moisture advection and energy remains well to the east, tropical moisture will creep into Mohave County and potentially Southern Nevada by Thursday. Weak ridging overhead and an increase in both temperatures and moisture may result in isolated storms locally, particularly for Mohave County. && .AVIATION...For Harry Reid...For the 06Z Forecast Package...Shower and thunderstorm activity have shifted to to the north of the valley leading strong gusts around 35 kts possible. More distant storms to the northeast and northwest will offer brief from those respective directions but overall winds look to come from due north. Into the late night, showers and storms will move northward with gusts quickly diminishing and winds becoming light and variable. Light to moderate southerly winds arrive into Tuesday afternoon and turn southeast into the early night. For the rest of southern Nevada, northwest Arizona and southeast California...For the 06Z Forecast Package...showers and storms have mostly focused to the north causing gusty northerly downdraft winds through the valley. Shower activity will continue to push north and east through the late night, lingering across Lincoln County into early Tuesday morning. Winds look to ease into the late night as the showers and storms exit. Expect mostly light winds and clearing skies through Tuesday morning with more moderate to breezy winds arriving into Tuesday afternoon before easing that evening. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Moore AVIATION...Murdock For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter