Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
689 FXUS65 KSLC 282253 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 353 PM MST Fri Nov 28 2025 .SYNOPSIS...A cold and wet pattern commences across the forecast area today as the first of at least three incoming systems pushes through the region. Light mountain snow is expected with todays system with more widespread snowfall with the second system on Sunday, perhaps bringing light valley snowfall to northern UT. && .DISCUSSION...Key Points: - Snowfall will either begin shortly or is currently ongoing across higher terrain of the Bear River Range. Light snowfall across higher terrain across more portions of northern UT and perhaps central UT will begin this evening. - A brief lull in activity is expected tomorrow, though a notable cool down across the area is expected following the passage of a cold front. - A second system looks to impact UT and southwest WY on Sunday bringing accumulating snowfall to the majority of our northern and central UT mountains through Monday morning. - The active pattern continues with another system looking to impact the area as early as Tuesday. Additional storms appear evident in the extended forecast as well, continuing the pattern. Per SPC Mesoanalysis, a broad shortwave trough is pushing through UT with an attendant cold front sweeping through the area as well. With this system remaining broad and weak, light snowfall is expected across the majority of our northern UT mountains this evening through early tomorrow morning. While most mountains across northern UT will see a trace at best, terrain favored in northwesterly flow such as the Cottonwoods, Uintas, and Bear River Range (primarily north of Logan Canyon) will see greater accumulations locally. The Cottonwoods and Uintas can expect around a trace to 4" from this system beginning later tonight. The Bear River Range stands out with this event given some uncertainty surrounding moisture quality, though 2-5" is broadly expected with a higher spread appearing evident north of Logan Canyon where 2-9" may occur this evening. Following the passage of the aforementioned cold front, seasonal normal temperatures to perhaps slightly below normal temperatures will usher into the forecast area tonight, lasting through the majority of this forecast. On Saturday, conditions remain relatively benign across the forecast area as transient ridging builds in to the area. Ridging quickly retreats to the southwest as another upper shortwave trough begins to push inland across the PNW late Saturday evening into early Sunday morning. The trough is forecast to continue deepening as it moves toward the forecast area with northern UT and southwest WY sitting within the left exit region of an upper jet streak, leading toward stronger ascent across the area. As such, snow totals across northern UT are expected to exceed what we are going to see from the incoming system this evening. Additionally, another frontal feature will pass through clocking winds to northwesterly resulting in more snowfall across northwest flow favored terrain. 25th to 75th percentile snowfall accumulations across the majority of our northern UT mountains range from 3-8" with our central UT mountains seeing roughly 1-5". The Wasatch will see locally higher amounts as snowfall is favored within a northwest flow regime with a 25th-75th percentile spread ranging from 5-12" with locally higher amounts possible. Lastly, there is around a 40- 50% chance that the Wasatch sees amounts greater than 9"(Winter Weather Advisory criteria for the Wasatch mountains), indicating that seeing higher end amounts within the range is quite realistic given the favorable flow regime. If this wasn`t exciting enough, there is still a non-zero chance (!) that our first measurable snowfall occurs across the Wasatch Front, Ogden Valley, and Cache Valley with this system. While this system isn`t the strongest, it will dive south in quick succession following tonight`s system keeping 700mb temperatures quite low. After tonight`s system passes through, 700mb temperatures will generally hover around -5C to -7C before Sundays system arrives. This will maintain snow levels around 3000-4000ft along a north- south gradient, increasing with southerly extent. Additionally, 700mb temperatures are forecast to continue cooling as Sundays system arrives. While this is favorable for valley snowfall, it`s unlikely that accumulations will be anything greater than 0.5" on the high end as ground temperatures remain above freezing across the Wasatch Front. However, benches along the Wasatch Front and northern valleys at higher elevations may see up to an inch from this system. Following the passage of a cold front on Monday associated with Sundays system, below normal temperatures are expected to fill into the area and will likely persist throughout the remainder of the extended forecast. As far as confidence intervals go, temperatures may be the only portion of the extended forecast that holds high confidence. The upper level pattern remains favorable for more troughs pushing into the PNW then diving south, though amplitude of each incoming trough and eastern/western/southern extent remains quite uncertain. As of now, around 3 possibilities are modeled regarding the outcome of the next system which is expected to occur on Tuesday (33% probability for each). 1). A western and deeper (stronger) solution would favor higher precipitation for northern UT / southwest WY. 2). A broad (weaker) solution would favor precipitation primarily across northern UT / southwest WY, particularly across higher terrain. 3). A broad and deeper (stronger) solution favoring increasingly widespread precipitation across nearly the entirety of the forecast area. This solution would likely favor valley snowfall as well as it draws down increasingly colder air, dropping snow levels markedly. As such, it is too soon to iron out any specific details given each scenario has an equal chance of occurring as of this forecast cycle. Thankfully, each solution provides at least some chance of improving snowpack across northern UT given this November has been unseasonably dry. Following the third system midweek, the upper air pattern remains somewhat uncertain at this time for the remainder of the week. Ensemble guidance indicate a near 50/50 split as to if we will maintain the troughing pattern, or if a ridge will build in and bring an end to the activity. && .AVIATION...KSLC...Northwesterly winds will remain in place in wake of a dry cold frontal passage. A period of mountain obscuration is expected to develop for a window focused within the 03-10z window, but VFR conditions will be maintained. .REST OF UTAH AND SOUTHWEST WYOMING...Mountain obscuration due to light mountain snow showers is expected over far northern Utah through this evening, gradually shifting as far south as the Central Wasatch into the early morning hours. Said, all TAF sites are expected to retain VFR conditions with winds remaining northwesterly in the north. && && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && $$ PUBLIC...Worster AVIATION...Merrill For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity