Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
328 FXUS65 KVEF 220317 AAA AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 717 PM PST Thu Nov 21 2024 .SYNOPSIS...Generally dry and warming conditions into Saturday. Low pressure off the Pacific Northwest coast will sag south, directing moisture into the Sierra Friday night into Saturday. This will result in high elevation snow in the Sierra. Winds will also increase across the Mojave Desert Saturday afternoon/evening. Another system will move across the region Sunday through Tuesday, bringing more widespread rain and mountain snow chances. && .UPDATE... Unsettled weather to the north in tandem with perturbations over the Sierra will allow for snowfall on the order of 2-8" above 7,000 feet along the Eastern Sierra Slopes, a Winter Storm Advisory remains in effect from 4 PM Friday to 4 AM Sunday. Elsewhere, expect warm and dry conditions through Saturday. The forecast remains on track with no updates needed at this time. && .PREV DISCUSSION...135 PM PST Thu Nov 21 2024 .SHORT TERM...Tonight through Saturday Night. Dry and quiescent conditions across the region today as we remain sandwiched between a ridge of high pressure to the east and a broad trough of low pressure off the Pacific Northwest coast. These conditions will remain the same through Friday. By Friday night and Saturday, the upper level trough will have sagged far enough south to direct moisture across the Sierra, resulting in high elevation snowfall. A Winter Weather Advisory has been issued above 7000 feet for the Sierra with 2-8 inches of snow expected between 7000 and 8500 feet and higher amounts near the crest. Additionally, a weak wave ejecting from this trough will also increase southwest winds across the Mojave Desert Saturday afternoon and evening, with peak gusts generally between 30-40 mph. Winds were overall increased compared to the previous forecast. Isolated areas of blowing dust will be possible as a result, mainly across western San Bernardino County. .LONG TERM...Sunday through Wednesday The trough will then weaken and most of the remaining energy and moisture associated with it will gradually transition east across the region Sunday through at least Tuesday. The main concern with this time frame will be somewhat more widespread precipitation chances and higher snowfall totals in the mountains (mainly the Sierra). That said, cluster analysis shows diverging solutions during this time frame. The primary question is how quickly this transition will happen and how much if any troughing remains over the far eastern Pacific. Around 20% of the ensemble members keep energy offshore through Tuesday night/Wednesday, while around 10% keep it all the way through Wednesday night/Thursday. The implications of this lingering energy would be to extend the period of precipitation chances out further into next week while also keeping temperatures several degrees warmer. In nearly all cases, temperatures will gradually cool through next week, after the trough makes its way through, leaving drying northwest flow across the region. && .AVIATION...For Harry Reid...Winds will remain under 10 knots and will follow typical diurnal directional trends through the evening hours. Winds will become light and variable overnight before settling in from the east on Friday morning. For the rest of southern Nevada, northwest Arizona and southeast California...With the exception of the Colorado River Valley TAF sites, winds at the remaining TAF sites will remain under 10 knots and will follow typical diurnal directional trends with periods of more light and variable winds as they transition. Winds at the Colorado River Valley TAF sites will favor a northerly direction through the afternoon, with KEED falling to a more westerly direction this evening while KIFP maintains a more northerly direction through the evening hours. Winds at KIFP and KEED will become light and variable during the overnight hours. FEW to BKN mid- to-high clouds with bases AOA 15 kft will continue to filter through the area, but should not cause any operational impacts. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Wolcott LONG TERM...Wolcott AVIATION...Stessman For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter