Area Forecast Discussion
Issued by NWS Reno, NV
Issued by NWS Reno, NV
272 FXUS65 KREV 100921 AFDREV Area Forecast Discussion National Weather Service Reno NV 221 AM PDT Mon Jun 10 2024 .SYNOPSIS... Temperatures across the region expect to rise again this week with near record values possible on Tuesday, Wednesday, and Thursday in some locations. Areas along and south of US-50 may also see a slight chance for isolated showers and thunderstorms during the afternoon and evening today and tomorrow. A cooling trend with increased winds looks likely going into the weekend. && .DISCUSSION... The latest RAP analysis shows the axis of an upper air trough over the eastern portion of the CWA with a trailing ridge to the east and a low to the west of the Baja Peninsula this morning. Current satellite imagery along with surface observations report generally clear skies over the CWA with dry conditions following Sunday`s precipitation. Going through today, models are forecasting the upper air trough departing eastward allowing for the western ridge to advance over the CWA during the day as well as cut off the southwestern low. With this pattern aloft, slightly warmer daytime highs could be expected at the surface with western NV seeing highs range from the upper 80s to middle 90s while the CA portion of the CWA sees highs generally in the 80s to lower 90s. As for precipitation chances, models are showing a 10-20% chance for isolated showers and thunderstorms during the afternoon and evening along and south of US-50 within the region. Better chances for rumbles of thunder may be closer to the Sierra Mountains with models showing 200-300 J/kg of MLCAPE during the evening, but not anticipating severe weather at this time. Any precipitation that occurs also looks to yield minimal moisture with QPF values generally less than 0.1 inches. Overnight low temperatures for the region expect to be around 2-5 degrees warmer than Sunday night`s lows. For Tuesday and Wednesday, forecast guidance shows the CWA keeping the ridge over the CWA as it broadens across the western two-thirds of the CONUS with the cutoff low remaining generally in place off the coast of the Baja Peninsula. On Thursday, models then project the cutoff low to move northeast across southern CA during the day and over the southern tip of NV overnight. The main story at the surface continues to be the above normal temperatures that may reach near the record values of a 1940 heatwave within the region. When looking at NBM probabilities for 100 degrees or more for the Reno-Tahoe International Airport (KRNO), there appears to be less than a 10% chance for triple digit temperatures on Tuesday and Thursday. But, KRNO sees around a 20% chance for reaching the 100 degree mark for high temperatures as this looks to be the hottest day of the week. The NWS HeatRisk product shows generally minor to moderate impacts related to heat across the CWA with some isolated high impact areas in western NV during the period of Tuesday through Thursday. It is definitely recommended to be prepared for this upcoming heat and to take precautions if you plan on being outdoors in the middle of the week. Make sure to stay hydrated, wear sunscreen, and wear light clothing in order to avoid heat related illnesses. While Wednesday and Thursday look to be mostly dry at this time, Alpine and Mono Counties may see up to around a 15% chance for isolated showers and thunderstorms during the afternoon and evening hours of Tuesday. Going into and through the weekend, ensemble guidance shows an upper air trough moving into the Pacific Northwest and pushing the ridge feature off to the east on Friday. This new trough continues its advance into the northwestern CONUS on Saturday with the CWA being underneath the trough`s base by the evening hours. On Sunday, the CWA stays under the base of the trough with the trough`s axis making its way over the CWA during the evening hours. At the surface, models are showing a potential cold front passing through the region on Friday allowing for a cooling trend to persist through the weekend along with some breezier winds. Forecast guidance continues to show lower chances for precipitation at this time due to a dry airmass moving into the region, but this will be monitored in case this starts to change in future model runs. -078 && .AVIATION... VFR conditions are anticipated for the REV TAF sites going through Monday with the western NV sites seeing northwesterly gusts up to around 18 kts beginning around 00Z that look to last a few hours. Southern portions of the region along and south of US-50 may see up to around a 20% chance for isolated showers and thunderstorms during the late afternoon and evening hours of Monday, but not anticipating impacts at TAF sites at this time. Density altitude concerns continue today through the remainder of the work week with temperatures staying well above average. -078 && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$