Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
010 FXUS65 KVEF 090758 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 1258 AM PDT Sun Jun 9 2024 .SYNOPSIS...A trough reaching the West Coast brings short-lived relief from the heat today and Monday, before high pressure builds overhead again and pushes temperatures back to dangerous levels Tuesday and Wednesday. The peak of the heat should only last two days, but the stretch of above normal temperatures which has been ongoing since late May will continue. && .SHORT TERM...through Wednesday night. Midnight satellite loop showed scattered cirrus over the Mojave Desert and convective debris clouds over the southern Great Basin. Surface obs showed generally light winds areawide and temperatures averaging a few degrees lower than 24 hours ago. The advertised heat relief is here as the weak trough pushes into the West Coast, but it won`t last long. Models are in good agreement showing this trough splitting (and there are already signs on mid level water vapor), with the northern piece zipping away to the east across the northern Rockies on Monday while the southern piece forms a cut off low off the southern California coast. This leaves a skinny east-west oriented ridge axis over our area, which builds through Wednesday, with 500 mb heights reaching 590 dam Tuesday and Wednesday. This will lead to another round of heat, with the NBM showing a 63 percent chance of Las Vegas reaching 110F again on Wednesday, and a swath of Major HeatRisk through the lower elevations of Inyo, Clark, and Mohave counties Tuesday and Wednesday. Thus, issued an Excessive Heat Watch for these areas. As far as thunderstorm chances go, high resolution models correctly forecast the downward trend in chances from Friday to Saturday, and the consensus is for chances to drop even further today and become nearly absent beginning Monday as heights build overhead. .LONG TERM...Thursday through Saturday. A cut off low that has been hanging out off the Baja California coast will lift northeast through the region Thursday through Saturday, with decent agreement among long term models in timing and overall set up as this occurs. A cool down in temperatures from the peak heat midweek is likely. For example, the probability for 110F in Las Vegas is around 60% on Wednesday, but quickly falls to 30% or less for the rest of the period. Temperatures will fall back closer to normal and HeatRisk drops to widespread moderate levels at most Thursday through the weekend. Most likely, it will remain dry with probabilities for any precipitation for Thursday through next Sunday remaining low to near zero. PWATs do increase to near normal levels as the low crosses the region Friday and Saturday, but with very dry low levels it makes sense that no measurable precipitation is currently expected. Expect afternoon breezes but no impactful winds with this system either. In general, the low should come through with minimal impacts, just will kick down temperatures a few degrees. && .AVIATION...For Harry Reid...South-southeast breezes persist through most of the day, only turning to the south-southwest after sunset this evening. Until then, wind direction is expected to be generally between 150-190. The probability of 10+ knot winds remains below 50% until around 17z, with a 60+% chance of 20+ knot wind gusts from 18z-00z. Wind speeds will gradually weaken during the evening and overnight hours. FEW-SCT mid and high clouds through most of the period, with cloud bases aoa 12kft. For the rest of southern Nevada, northwest Arizona and southeast California...Another day of breezy south-southeast winds across most of the area, with wind gusts this afternoon of 20-25 knots. Again, the exception to this will be KDAG where wind direction is forecast to be west-southwest. There`s a low (15%) chance of a shower at KBIH this afternoon. Should this materialize, there could be a brief period of erratic outflow winds. Otherwise, the rest of the sites remain dry as FEW-SCT mid and high clouds linger through the day. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Morgan LONG TERM...Nickerson AVIATION...Woods For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter