Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
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546 FXUS65 KVEF 181202 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 402 AM PST Tue Nov 18 2025 .KEY MESSAGES... * Widespread rain and mountain snow continues across the region today and tonight, with periods of locally heavy rainfall possible at times through this evening. Precipitation will linger into Wednesday and Thursday, but should not be as widespread, steady, or as impactful. * A Flood Watch remains in effect as heavy rain at times could lead to flooding in low lying and sensitive basins. Winter Storm Warnings are in effect as heavy snow remains expected in the higher terrain of the Spring Mountains, Sierra, White Mountains, and peaks in the southern Great Basin. * Another system will dig into the region late this week with continued active weather possible, but the track of the low is not as favorable for widespread precipitation. Mainly, it will reinforce the continued colder than normal temperatures. && .DISCUSSION...through Monday. Radar through the early overnight showed two main features- an area of steady precipitation shifting east into Inyo County associated with the forcing ahead of the upper level low moving into the central California Coast and then scattered showers developing in southwest Arizona rotating north along what satellite shows as a warm conveyer belt. So far, short term hi-res models are handling these two areas decently comparing the ongoing situation to model trends. In general, expecting these areas to shift north and east, filling into much of Inyo County, southern Nevada, and Mohave County through the morning. Highest concern for impacts through the morning is southern Mohave County where HREF 3-hr QPF PMMs is targeting with 30%-50% probabilities for over 1in of rain. This is where impactful rainfall amounts are already expected for today, and any overachieving (which is possible given warm-conveyer belt dynamics, training precipitation, plus any potential convection the HREF is highlighting in the area this morning) putting the area at 1.50-2.00 inches total this morning. Further north and west, steady light to moderate rain is expected through the morning, with heavy rain possible at times which will drop 0.25-0.50 inches across a large area. Rain should be falling for the Las Vegas morning commute. Through the rest of the day, this trend will continue as bands of precipitation rotate north through the region as the low slowly shifts further inland. Thunderstorms are not out of the question this afternoon as HREF 1-hr probability for thunder has increased quite a bit from previous runs, especially in southern Mohave County this morning then in southern Nevada this afternoon. By this evening, these bands should dissipate with the focus for precipitation shifting into southern Nevada and Mohave County for tonight and Wednesday. In general, its going to be a wet day with no major shifts from previous forecast or overall forecast thinking. A Flood Watch is in effect through Wednesday early morning for Inyo, eastern San Bernardino, far southern Nevada, and southern Mohave County to capture the area at highest risk for rainfall and flooding impacts, which seems to be on track based on the latest model guidance. Snow levels around 7000ft through the day will drop to around 6000ft tonight into Wednesday. This drop should occur after a bulk of the precipitation is done, so winter impacts should remain above 7000ft. A Winter Storm Watch has been issued for many terrain areas through tonight with the heaviest snow is expected. Moderate winter storm impacts are likely with a low (20%-30%) chance for major winter storm impacts. Rain and snow should be limited on Wednesday and Thursday as the low moves overhead. Some lingering moisture will remain over the area but with minimal forcing, precipitation will be isolated and less organized. Model reflectivities on Wednesday suggest a more scattered, cold core-looking set up in the afternoon under the low`s center in southern Nevada, with potentially more steady rainfall further west as southerly flow continues to brush Mohave County. Models are trending higher moisture longer over the area, which could result in an increase in precipitation coverage and amounts, but in general both forcing and moisture will be lower than what is currently ongoing so impacts will also be lower. On Thursday, the first low finally starts to lift out into the Four Corners area, but right on it`s heels is another trough digging into the West Coast. Trends continue to favor a more southerly and slower track, with precipitation chances Friday and Saturday focused to the far southern portions of the forecast area- however, there remains the chance of some light showers and cooler temps as it moves off the coast. After that, a much anticipated break is expected by Sunday into the beginning of next week as ridging builds in temperatures slowly moderate. && .AVIATION...For Harry Reid...For the 12Z Forecast Package...Clouds will lower and thicken early this morning, with chances for rain beginning as early as sunrise. The rain will lead to lower ceilings, with 60% or greater chances for ceilings at or below 3000 feet from noon through midnight. Rain chances are expected to decrease overnight into early Wednesday morning, but ceilings at or below 5000 feet are likely to linger through the day. For the rest of southern Nevada, northwest Arizona and southeast California...For the 12Z Forecast Package...Rain and snow, low ceilings, and terrain obscuration will be the main concerns this period. Snow which had been occurring in the northern Owens Valley overnight should change to rain after sunrise, and rain and mountain snow will overspread much of the region through the day. The best chances for improving conditions this afternoon will be in San Bernardino County, expanding to Inyo, Esmeralda, and Nye counties overnight, although MVFR ceilings could linger. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Nickerson AVIATION...Morgan For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter