textproduct: Salt Lake City

KEY MESSAGES

- High elevation snowfall will bring travel impacts to elevations above 7500-8000 feet through this morning.

- An active weather pattern will follow this initial storm as we head into early next week, bringing continued threat for high elevation snowfall and travel impacts.

DISCUSSION

Widespread showers are currently ongoing across a majority of Utah and southwest Wyoming this morning as an upper- level shortwave pivots through the region. Greatest coverage is favored across across northern Utah as a band of heavier precipitation currently stretching from the northern Great Salt Lake Desert to the Cache Valley is expected to continue pushing southeastward through this morning. Northwesterly flow aloft has allowed for increased cold air advection and thus wet snow is being observed down to 6500-7000 feet this morning. Those with plans to travel over mountain routes above these elevations this morning should be prepared for delays, use extra caution, and consider alternate plans. This band is expected to taper in intensity through the remainder of the morning, eventually diminishing areawide by late morning/early afternoon, allowing conditions to improve through this afternoon and evening.

The pattern remains active through the remainder of the weekend into early next week as a progressive longwave troughing pattern along the west coast brings additional rounds of valley rain and high elevation snow Saturday through Monday. The first round arrives around late Saturday into early Sunday as a decaying atmospheric river quickly shifts through the region, bringing increased southwesterly winds regionwide and a quick shot of overall precipitation mainly to northern Utah. The axis of the aforementioned longwave trough is expected to gradually shift eastward Sunday into Monday, with an associated strong upper-level jet bringing an efficient Pacific moisture tap to the region. This timeframe will be the one to watch for potential travel impacts from accumulating snowfall to mountain routes across Utah and southwest Wyoming.

There remains a fair amount of agreement in a longwave trough deepening across the western US the latter half of next week, introducing much cooler temperatures areawide. Specific impacts from this system are uncertain at this time, but it is worth mentioning that temperatures aloft will be cold enough between Thursday and Friday for snow in valley areas across northern Utah and southwest Wyoming as ensembles currently suggest H7 temperatures anywhere between -9 to -16C.

AVIATION...KSLC

IFR to low-end MVFR conditions and mountain obscurations will continue along with intermittent rain showers through around 18z before a gradual improvement in VIS and CIGS through the early afternoon hours. Winds are expected to remain a light northerly through around 14-15z before settling at light southerly through tonight.

REST OF UTAH AND SOUTHWEST WYOMING...Light to moderate precipitation will continue to bring IFR to MVFR conditions and mountain obscurations to most northern Utah and southwestern Wyoming terminals through at least mid-morning before precipitation becomes increasingly confined closer to the higher terrain with gradual improvement in VIS and CIGS for the rest of the morning and early afternoon hours. Across southern Utah, precipitation will be light and more isolated to scattered, but IFR to MVFR conditions will also be common through around mid-morning.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Winter Weather Advisory until 11 AM MST this morning for UTZ110>113-117.

Winter Weather Advisory until 5 AM MST early this morning for UTZ125.

WY...None.