Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
053 FXUS65 KSLC 122216 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 316 PM MST Wed Nov 12 2025 .SYNOPSIS...High pressure will yield dry and mild conditions through Thursday. A cutting off Pacific system will then approach and lift through the area Friday into Sunday leading to a cooler and more active period. While low confidence, there is then some indication of yet another storm system thereafter early in the upcoming week. && .DISCUSSION...The axis of a mid level ridge is gradually shifting eastward through the Rockies today. High pressure associated with the ridge is resulting in continued dry and mild conditions locally, with afternoon temperatures running around 5-10 degrees or so above normal. With the high pressure overhead mixing has remained somewhat limited though, and many sheltered valleys are seeing another day with some hazy conditions. Otherwise, just seeing some mid/upper level moisture moving through as southwesterly flow increases, and in turn a corresponding increase to cloud cover. This does not appear to be very impactful however aside from resulting in slightly warmer overnight lows, as well as potentially decreasing the viewing potential of any auroral activity (see the Space Weather Prediction Center for such forecasts or more detailed space weather information). Temperatures increase slightly and peak on Thursday as a system cutting off along the Pacific coast further enhances southwesterly flow overhead. This will lead to a slightly more breezy day Thursday with fairly widespread gusts in the 20-30 mph range across most of Utah`s western valleys. Moisture begins to increase more on Friday as the aforementioned cutoff system slowly shifts eastward. Isolated to scattered precipitation chances increase in turn through the day and then remain slightly elevated into early Saturday. With limited cold air given the cutoff nature of the low, temperatures will only gradually nudge downward and snow levels will generally remain above 9500 feet. General ensemble consensus supports that this cutoff system will gradually eject northeastward through the region late Saturday on through early Monday. This period will see a more marked increase in available moisture as well as synoptic forcing given the proximity of the low. As such, precipitation chances become more widespread through this period. The majority of the precipitation in this system is favored to fall during a south to southwesterly deep flow, with orographics in turn favoring the terrain that does well in such a regime. Given limited cold air advection, snow levels will start out above 9500 feet and only start gradually dropping through Sunday to around 7000-7500 feet or so by early Monday. Given the long duration to the system and ample moisture with favorable IVT, QPF totals are pretty decent overall. Generally forecast carries around 0.50" to 1.00" water for much of Utah`s mountains and around 0.10" to 0.40" for most remaining valley locations, with locally higher amounts in orographically favored locations. Lack of better cold air availability will limit snow accumulations quickly below 8000 feet or so. A general 3-6" above that seems reasonable based on the forecast, with locally up to 9" or so possible in favored areas such as the Tushars and Upper Cottonwoods. Lower confidence is noted at the tail end of the forecast period, but models do suggest an active pattern may continue. Many of the deterministic runs carry some sort of trough deepening through the PacNW, but differ on exact evolution, especially in regards to another potential cutoff scenario. There seems to be limited agreement amongst individual ensemble members as well as to how exactly this shapes up. As it stands the origin of the associated airmass would be more favorable for a better intrusion of cold air, but again, lots of uncertainty. For example, at KSLC there is a wide spread in forecast H7 temperatures with the 75th percentile at -3C, median at -7C, and 25th percentile at -11C. The colder of those scenarios would likely allow for some lower elevation flakes to mix in, while the warmer of them would lead to another higher elevation snow event. For now forecast leans nearer to median to cooler side of the distribution, which yields additional widespread mountain snow accumulations on the order of around 5-10" with some locally higher amounts. That said, given how seemingly the pattern so far this season has seen forecast storms trend more cutoff/warmer/weaker (or a combination), would caution looking at exact numbers rather than how it trends. && .AVIATION...KSLC...VFR conditions will prevail at the KSLC terminal through the TAF period. Cigs are likely to reach at or near 12kft agl by sunset and persist through early morning. Light northerly winds are expected to shift to southeast by 03z, becoming gusty by late morning and likely remaining south through the afternoon. .REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions persist for all regional terminals through the TAF period. Mid-level cloud cover is expected to increase into the evening and decrease after sunrise. Winds will likely follow typical diurnal patterns into tomorrow morning. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && $$ PUBLIC...Warthen AVIATION...Verzella For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity