829 FXUS65 KREV 180955 AFDREV Area Forecast Discussion National Weather Service Reno NV 255 AM PDT Thu Mar 18 2021 .SYNOPSIS... Our next storm will bring mountain snow, light valley rain showers, and gusty winds Thursday and Friday. A few light snow showers may linger on Saturday. It will remain cool over the weekend followed by the potential for a quick moving storm Monday. The forecast is looking warmer and drier by the end of next week. && .SHORT TERM... No major adjustments were made to the previous forecast. The storm forecast to impact the region is still on track to move in today bringing high elevation snow to the Sierra, rain/snow to lower Sierra elevations, and gusty winds with a few rain showers expected for western Nevada through Friday. The character of this storm continues to be of the warmer variety with snow levels around 6000ft for far northeast California, around 7000ft for the Tahoe Basin, and 7500+ for Mono County. As such, 6-12 inches of snow is expected for the the higher elevations 7000+ft in the Sierra with rain for Sierra valleys. Snow levels begin to fall tonight which will be the best chance for a slushy inch or two to accumulate in lower valleys of the Sierra. The SW to NE trajectory of the 105kt 300mb jet will support gusty southwesterly ridge winds that will promote strong shadowing across the Sierra into western Nevada. Expect a rapid drop in precip from the Sierra crest to the Sierra Front. By Friday, the cold core will be strafing the region resulting in low, 5-10% chances of a thunderstorm; for the most part, expect mainly showers that could cause some minor accumulations of snow pellets. Given the moderate amounts of liquid associated with this system, little rain is expected for western Nevada. The core of the jet will not move over the higher terrain of the Sierra until late this afternoon. Expect breezes to increase through the day with south-southwesterly surface gusts 25-40 mph for western Nevada and Sierra locations. Gusty winds today could cause some brief fire weather concerns for southern Mono County before precipitation can track down the Sierra crest. Locations susceptible to downsloping, like Washoe Valley, will likely stay breezy to gusty through the overnight hours through Friday afternoon. Winds taper Friday afternoon, shifting more northerly with breezy gradient winds and cooler temperatures. Expect cooler temperatures for Saturday, 5-10 degrees below average, with some lingering showers along the Sierra and Sierra Front. Easterly ridge winds could be gusty for Sunday into Sunday night with some mountain waves west of the Sierra crest. Boyd .LONG TERM...Next Week... No big adjustments were needed this morning as models continue to struggle with the position of the eastern Pacific ridge and thus systems dropping down the east side into the Great Basin/Rockies. Cluster analysis is no big help other than the mean showing the ridge off the west coast and trough centered over the Rockies, putting the Great Basin in the right position. Deterministic runs of the GFS/ECMWF continue to track systems southward into the Great Basin, one around Mon-Tue and another Thursday. For now, we have maintained a slight chance of showers Monday-Monday night with the first shortwave and cooled temperatures ever so slightly below the blended guidance Tuesday. For mid to late week, we generally followed the blended guidance as confidence erodes further. Any QPF will be light if it occurs. It also appears that it will remain seasonally cool (near to slightly below normal) next week with a delay in any significant spring warmup. Hohmann && .AVIATION... Winds aloft will continue to increase today and remain strong and gusty tonight into Friday as a cold front/upper level jet maxima move through the Sierra and western NV. Peak gusts 25-30 kts at area terminals today, but there will be some LLWS and mtn wave turbulence. LLWS may become a little less 21-02Z with better mixing, but some areas with channeling winds by terrain (KTVL) will see it all day. More wind shear tonight into Friday along with some gusty winds at all terminals Friday. As for precip/CIGS, some MVFR CIGS in -SN late this morning and afternoon along the Sierra crest with mtn obscuration. Snow increases and becomes more widespread in the Sierra tonight and early Friday until the cold front passes. A period of IFR likely (80%) from 00-18Z Friday in SN, possibly lingering to 21Z in the eastern Sierra down to KMMH. Only a brief period of spillover into the Highway 395/I-580 corridor as the front works through the area tonight and early Friday (possibly MVFR at times for Sierra Front airports). Precipitation will become more showery behind the front with the main focus on the Sierra with periods of MVFR conditions Friday afternoon into Friday night. Hohmann && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$ For more information from the National Weather Service visit... http://weather.gov/reno