222 FXUS65 KVEF 080946 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 146 AM PST Sun Nov 8 2020 .SYNOPSIS...A second round of rain and mountain snow will overspread the region today, with several inches of snow likely above 5000 feet. Rain and snow will end from west to east tonight, with only a few showers lingering in northern Mohave County Monday morning. Dry weather will then return for the upcoming week, and temperatures will slowly climb just a little each day, reaching near normal by next weekend. && .SHORT TERM...Through tonight. Early morning satellite loop showed yesterday's storm exiting stage right, with today's storm digging through Oregon into California, carving out a deep, cold trough. Over our area, skies were clear to partly cloudy over the Mojave Desert, while low and mid level clouds were slowly expanding south over the southern Great Basin. These clouds were already producing light snow, and as lift increases through the morning, the snow will become more widespread. Thus, the Winter Weather Advisory looks good. By afternoon, the forcing will dig south into the Mojave Desert, with rain (and snow above 4000 feet) breaking out there as well. There are numerous concerns in the details here, including just how much snow accumulates in the higher terrain, and also thunderstorm potential over Mohave County, particularly south of Kingman. Models are suggesting a low CAPE/high shear environment there this afternoon, which is a bit worrying. If the CAPE is too low, then the high shear tears apart updrafts before they can organize; but if there is enough CAPE to develop and support updrafts, then the high shear is favorable for rotation to develop, supporting hail and perhaps even weak tornadoes. Not much confidence in this worst-case scenario, but it's worth keeping in the back of the mind. As the upper level trough axis slowly crosses our area from west to east this evening and tonight, precip chances will trend downward. Behind the storm, even colder air will be in place, and if clouds clear out and allow for radiational cooling, freezing temperatures could occur in areas such as Shoshone, Trona, Fort Irwin, and parts of the Morongo Basin. Upgraded the Freeze Watches to Warnings for these areas. .LONG TERM...Monday through Saturday. By Monday morning, the system that brought the rain and high elevation snow will have shifted its axis to the east of the Colorado River Valley and PoP chances will be on the decrease through the rest of the day. As moisture exits with this system, heights will slowly recover through the rest of the week, but remaining in a general northwest flow regime across the region. As per the previous forecast discussion, a "parade" of varying shortwave intensities within the northwest flow will push through the region. However, latest trends are drier unfortunately from Monday afternoon through at least Thursday. Thus, little more than a few breezy afternoons and a gradual increase in temperatures through the week look likely. However, by late in the week, a much more progressive shortwave looks to be on approach from the Pacific NW. The 00Z suite of the GFS/ECMWF/Canadian have come to much more agreement than the 18Z runs, but still quite a bit of uncertainty in the depth of the low and how much moisture it will be bringing with it. One thing that stands out in all solutions is the unfavorable orientation of the better moisture advection, broad-siding the Sierra and serving to significantly reducing potential QPF for the Great Basin. Latest NBM this evening seems to reflect this well, keeping precip for the late week and weekend confined to the eastern Sierra and the northernmost portions of the CWA. Perhaps the feature to keep a closer eye on is potential ridgetop winds Friday/Saturday as the low pushes over the Sierra Nevada. While ensemble means are highlighting a low end potential for gusts over 30 kts for the eastern Sierra, mid and upper level winds look quite impressive with a WNW orientation over the range. This may result in a trend towards increasing wind potential throughout the week. && .AVIATION...For McCarran...Gusty southwest winds are expected to continue through Sunday morning, along with low-level wind shear below 2 Kft of 30-45+ knots. Southwest winds will increase through the morning peaking late morning through the afternoon with gusts to 30-35 knots. Winds are expected to decrease and shift more westerly this evening. A wind shift to the northwest is possible tonight, but confidence is low on the timing and magnitude of the northwest winds at KLAS. Northwest winds may make it to the terminal between 06-09Z tonight, but are more likely shortly after sunrise Monday when the temperature inversion breaks. Clouds around 5-6 Kft will remain through Sunday, generally along the surrounding mountains with increasing coverage later this afternoon. Vicinity shower chances increase this afternoon between 21-00Z, with lower confidence on showers impacting the terminal directly. Though, if a shower does move over or near KLAS, expect ceilings down to 3-4 Kft and erratic and potentially gusty winds. For the rest of southern Nevada, northwest Arizona and southeast California...Gusty south to southwest winds are expected to remain through the early morning across much of the region, expect at KBIH where breezy north winds are expected. Winds will peak by the afternoon with gusts to around 25-35 knots. Stronger winds will be possible at KDAG with gusts to 40 knots. Winds will relax some this evening at most terminals, becoming occasional gusts to 15-20 knots by tonight. Scattered showers with SCT-BKN clouds with bases down to 3-5 Kft, producing localized mountain obscuration will be possible again later this morning through the evening. Drier conditions are expected tonight behind another frontal passage. && .CLIMATE...Near record or record cold temperatures are possible for parts of the area today and Monday. The table below shows the record low maximum or cold high for each location and the year the record was last set, followed by the forecast temperature. LOW MAX Sun NOV 8 Mon NOV 9 Record(Yr)/Fcst Record(Yr)/Fcst Las Vegas 55(1946) / 55 55(1966) / 55 Death Valley 62(1920) / 64 65(1919) / 65 Kingman 53(2011) / 50 45(1946) / 50 Bishop 47(2004) / 47 43(1982) / 50 Barstow-Daggett 57(1945) / 57 59(1966) / 57 Desert Rock 56(2011) / 48 54(2000) / 50 The table below shows the record low minimum for potential record-setting locations and the year the record was last set, followed by the forecast temperature. LOW MIN Mon NOV 9 Record(Yr)/Fcst Bishop 16(2011) / 18 Desert Rock 29(1998) / 30 && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts from the incoming storm according to standard operating procedures. && $$ SHORT TERM...Morgan LONG TERM...TB3 AVIATION...Kryston CLIMATE...Kryston For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter