000 FXUS65 KVEF 022139 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 245 PM PDT Mon Jun 2 2025 .SYNOPSIS...Additional rounds of showers and thunderstorms are possible through midweek as sufficient moisture and instability remain in the area. Precipitation totals should be light and most activity will take place over high terrain. The area slowly dries out and temperatures begin to climb as a ridge builds later this week. && .DISCUSSION... The upper low that helped draw in tropical moisture has shifted off to the east leaving behind plenty of low level moisture. Dew points across the region are currently in the 40s and 50s, which is very unusual for June. So far today, showers and thunderstorms have been firing along the Sierra and White Mountains of Inyo County and across portions of northern Lincoln and central Nye counties. These areas are currently seeing the greatest instability with CAPE values in the 500-1000 j/kg along with LIs ranging from 0/-2 deg C. Storms over the Sierra and White Mountains will gradually decrease this evening with loss of daytime heating, but the storms over Lincoln County have the potential of maintaining and expanding this afternoon and evening as they move south. Those storms will be moving into areas that are seeing increasing instability as the earlier cloud cover continues to erode. Along with the increasing instability, high dew points and high PWs will lead to some storms producing brief heavy rain and minor flooding concerns. We did get a spotter report of small hail near Eagle Valley in Lincoln County as the storm went overhead. While most of the thunderstorm activity is expected to remain in Utah, areas of southern Lincoln, northeast Clark, and northern Mohave counties could see some stronger storms as we go through the afternoon and into the evening. We could also see some gusty outflow winds as DCAPEs in the area are around 1000 j/kg and it is possible that some of those winds could make it into the Las Vegas Valley. Storms will gradually diminish late tonight. Storms Tuesday are expected to be more favored over the southern half of the CWA as deep moisture remains in place. PWs will still be around 200-300 percent of normal which translates to around 1.00" - 1.50" inches. With plenty of morning sunshine this should translate to scattered showers and thunderstorms in the afternoon as conditions will remain rather unstable. Most of these storms will favor the higher terrain, but some valley locations could see a storm or two. Flash flooding could be more of a concern as winds aloft remain around 10 kts or less. On Wednesday, another low off the southern California coast will begin to shift inland. This low will take a very similar path to the previous low and although there isn`t a significant amount of tropical moisture available, the latest models indicate increasing PWs and surface dew points once again. This will lead to more scattered showers and thunderstorms over the southern half of the CWA. Again, these will likely be favored over the higher terrain, but any storms could produce heavy rain. WPC has added our eastern counties, including Lincoln, Clark, and Mohave into a marginal Excessive Rain Outlook. .LONG TERM...Thursday through Monday. Weak northwest flow will continue across the region late in the week. A series of weak short waves will move through the flow and interact with lingering moisture, resulting in slight PoPs through early Friday. The best chances will be over the southern Great Basin and Arizona Strip. The remaining moisture should move east of the area by Friday afternoon, bringing an end to the precipitation chances. Despite the shortwaves, a high-pressure ridge building over the eastern Pacific and northern Mexico will result in increased 500 mb heights across the Desert Southwest. As such, temperatures will climb back to 4 to 8 degrees above seasonal norms heading into the weekend, and temperatures approaching 10 degrees above normal heading into next week. This will result in desert valleys experiencing high temperatures in the 100s once again, and widespread "Moderate" Heat Risk from Sunday onward. && .AVIATION...For Harry Reid...For the 18Z Forecast Package...Most likely, the terminals will see light winds favoring the east early that become south to southeast at 8-10KT around 21Z today, then becoming diurnal after sunset. There is a low chance that a push of northeast winds moves through the valley around 06Z- if this did occur, northeast winds would likely gust over 20KT between 06Z-09Z before diminishing for the rest of the night. On Tuesday, south to southeast winds will develop again and should be similar to what occurs today. A few thunderstorms are possible this afternoon in the nearby mountains to the north and west, but in general not expecting convection or thunderstorm impacts today. There is a better chance, about 30%, for nearby thunderstorms to develop in and around the valley on Tuesday after 20Z which could produce lightning, sudden gusty erratic winds, moderate to heavy rain, and CIGs below 8000ft For the rest of southern Nevada, northwest Arizona and southeast California...For the 18Z Forecast Package...Light rain currently in Mohave County will diminish in the next hour or so. Convection this afternoon will favor the terrain of Lincoln, Clark, and Mohave counties as well as in the Sierra. Any thunderstorms today could produce lightning, CIGs to 5000ft, brief heavy rain, and sudden gusty winds. The highest threat of outflow winds will be in the Sierra, including at KBIH where southeast winds could be interrupted by west to southwest outflow winds between 21Z and 03Z. THe highest threat for heavy rain and 5000ft CIGS will be in Clark and Mohave counties. Low confidence that a complex of thunderstorms in southwest Utah will push an outflow through northeast Clark and northern Mohave after 00Z tonight with gusts over 30KT possible. Outside of convection, south to southwest winds around 10 KT will develop across the region this afternoon. Light winds return tonight before similar winds return late Tuesday morning and afternoon. Additional convection may develop Tuesday afternoon along and south of the I-15 as well as in the Sierra. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Gorelow LONG TERM...Planz AVIATION...Nickerson For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter