Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
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815 FXUS65 KVEF 290027 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 525 PM PDT Wed Oct 28 2026 .KEY MESSAGES... *Dry and seasonable conditions continue through Thursday. *Precipitation chances and cooler temperatures return to the region late this week and continue through the weekend. *Breezy, cool, and dry conditions return early next week. && .DISCUSSION...Through Tuesday. Zonal flow aloft continues across the region, though water vapor imagery indicates a fetch of mid-level moisture translating eastward, yielding an increase in cloud cover. Skies will become mostly cloudy overnight tonight, with additional influence from moisture advecting northward through the Gulf of California and into the Lower Colorado River Valley from TS Vance, currently located just to the southeast of Baja California Sur. Despite the increase in moisture, any precipitation will hold off until late Thursday night, with dry conditions and near normal temperatures persisting until then. On Thursday, flow aloft will transition to southwesterly ahead of a deepening trough off of the West Coast. The aforementioned moisture plume associated with TS Vance will result in precipitable water values increasing to 1 to 2 standard deviations above normal for late October, resulting in a return of shower and thunderstorm chances across Mohave County and portions of Clark and Lincoln County late Thursday night and continuing into Saturday. The aforementioned trough will continue deepening along the West Coast, developing into a split flow scenario with a secondary shortwave developing near southern California, while the core of the trough remains over the Pacific Northwest. This evolution will limit the winds that are generally expected with these systems, though as the trough axes move over the region during the weekend, precipitation chances become widespread Saturday evening through Sunday as additional subtropical moisture is routed into the region and precipitable water values increase to over 4 standard deviations above normal. There remains uncertainty in just how much precipitation will occur, with the current forecast ranging from around a quarter to a half inch across lower elevations, and up to an inch and a half in the mountains and localized spots across Mohave and eastern Lincoln Counties, where precipitation will be prolonged. Changes in the timing and trajectory of the trough as well as characteristics of the moisture return would result in changes to the precipitation forecast, thus, confidence in timing and amounts is moderate. Mountain snow is another expectation with this weekend`s system, mainly over the Sierra and the Spring Mountains. Snow levels still look to remain at or above 8500 feet through a majority of the event, with snow levels dropping as precipitation moves out of the region. Accumulations of wet snow at the peaks could be up to 4 to 6 inches, once again, dependent on overall QPF. Precipitation is expected to quickly come to an end from west to east through Sunday night. As the trough departs the region early next week, a tightening gradient on its western periphery is expected to result in breezy to gusty conditions on Monday, especially across the southern Great Basin. Gusty conditions are expected to diminish through Monday evening for most, though terrain-enhanced gusts through the Lower Colorado River Valley may persist into Tuesday. Cooler temperatures will also stick around early next week, in spite of shortwave ridging progged to build over the region in the wake of the departing trough. Highs will remain around 5 degrees below normal for most through Tuesday with dry conditions expected. && .AVIATION...For Harry Reid...For the 00Z Forecast Package... SE winds around 10 kt with gusts to 20 kt continue through sunset, then diminish. Expect a shift to S winds after 03z but with speeds at or below 8 kt, then light and variable winds favoring a NW direction after 10z. Expect a similar diurnal wind pattern tomorrow with winds favoring E-SE directions and speeds largely under 10 kt. Increasing mid-level and high clouds are expected through the forecast period, becoming SCT-BKN around 15kft Thursday morning onward. VFR conditions prevail. For the rest of southern Nevada, northwest Arizona and southeast California...For the 00Z Forecast Package...Daily diurnal wind patterns expected through the TAF period with speeds remaining between 5-10KT. KBIH may be the exception as stronger SE winds develop after 19z tomorrow with speeds 10-15 kt and gusts to 25 kt through sunset. VFR conditions will continue with increasing mid- level and high clouds through the forecast period with bases at or above 15kft. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Phillipson AVIATION...Moore For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter