Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
261 FXUS65 KVEF 311019 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 215 AM PST Fri Jan 31 2025 .SYNOPSIS...High pressure will move over the area today then a low pressure system and associated atmospheric river will impact northern California and the Great Basin over the weekend into next week. The Sierra will intercept much of this moisture with limited chances for spillover into Inyo and Esmeralda counties over the weekend. Widespread 20 to 40% chances of precipitation will spill into the southern Great Basin Tuesday through Thursday. && .SHORT TERM...Today through Sunday. A ridge of high pressure over our region will be pushed to the east today as a Pacific System shapes up in the form of a developing atmospheric river in the base of a Pacific Northwest low. This will direct abundant Pacific moisture from near Hawaii, aka Pineapple Express, into central and northern California Saturday through Sunday and beyond. The main impact for our southern Sierra zones will be a likely mix of rain and snow (70-80% probability), Saturday morning through Saturday evening with any significant accumulations confined to elevations above 10,000 feet due to the relatively warm subtropical air mass. There is 40 percent probability that light rainfall may spill into the Owens valley. The moisture plume is then forecast to lift northward late Saturday night with chances of precipitation diminishing to less than 20 percent on Sunday. Strong winds will also develop over the Sierra ridgetops Saturday morning through Sunday evening and high res models indicate downslope winds will likely gust over 40 mph into the Owens Valley near the foothills during this period. A Wind Advisory will be in effect for these zones from 4 AM Saturday morning until 10 pm Sunday evening. Models also indicate wing gusts over 40 mph likely spreading across northern San Bernardino County from 10 AM Saturday morning through 10 PM Saturday evening and a Wind Advisory will be in effect for these zones. The rest of the forecast area will remain dry and see temperatures climb 4-5 degrees each day Saturday and Sunday under increasing high clouds. This translates to maximum temperatures climbing into the 70s across most of the Mojave Desert region by Sunday. .LONG TERM....LONG TERM...Monday through Thursday. The start of the next work week will be characterized by above- average temperatures and partly-to-mostly cloudy skies as the stream of atmospheric river moisture shifts southward across the Desert Southwest. There is still a great deal of uncertainty regarding how much moisture will make it over the Sierra crest and into the Mojave Desert, with about half of ensemble members across desert valley locations indicating they will remain dry and the other half anticipating modest measurable precipitation. Regardless, we can expect an increase of moisture enough to warrant cloudy skies across the region through the work week along with above-average temperatures thanks to the warm nature of this moisture. The warmest day of the forecast period will be Monday, with a current forecast high for Las Vegas of 76 (daily record for February 3rd is 77 degrees set in 2018). Temperatures will gradually decrease as the week progresses. && .AVIATION...For Harry Reid...Winds will follow a typical daily pattern, shifting from the southwest to the northeast later this morning, then to the northwest after sunset. Speeds remain under 10 knots. High clouds with bases around 20kft move in this morning, increasing in coverage through the day. For the rest of southern Nevada, northwest Arizona and southeast California...Light winds following typical, daily patterns are expected across most of the area today. High cloud cover increases in coverage across the area today and tonight. At KBIH, lower clouds are expected to build in overnight with heights as low as 6kft by early Saturday morning. Showers develop over the Sierra overnight, but these should remain out of the vicinity of the terminal. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Adair LONG TERM...Soulat AVIATION...Meltzer For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter