textproduct: Salt Lake City

KEY MESSAGES

-Valley rain and mountain snow will become increasingly focused over eastern Utah on Wednesday as a storm system continues to slowly cross the Desert Southwest.

- In the wake of the storm system, overnight lows near or below freezing are expected in some outlying valleys of western Utah both Wednesday and Thursday mornings,

- Dry conditions are expected Thursday through early next week with a gradual warming trend as high pressure builds off the Pacific coast. A more active pattern may return by the middle of next week.

DISCUSSION

A Pacific Northwest low is centered over northwest Arizona this evening. A moist and unstable northerly flow remains in place over Utah and southwest Wyoming under the influence of this system, though associated valley rain and mountain snow has become increasingly spotty. Along with the precipitation, the system has also brought quite unseasonably cold temperatures, with maxes today having run 15-20F below seasonal normals. With some pockets of clearing in this airmass, some outlying valleys over western Utah will see lows near or below freezing, which could bring some impacts to agricultural activity. Going Freeze Warning covers this threat well. The threat of freezing lows will continue through at least Thursday morning.

The low is on track to trek across Arizona during the morning before sliding northeast into Colorado Wednesday afternoon, noticeably slower than what guidance was indicating yesterday, another example of models struggling with closed lows. Thus, the threat of showers will continue tomorrow, focused primarily over eastern Utah. The position of the low could also bring some locally gusty winds. Currently, the north/northeasterly flow is creating a pressure gradient modestly favorable for gap winds over prone areas of Washington county. However, associated cold advection is unimpressive, limiting the threat. By Wednesday night/Thursday morning, the position of the low will bring a more uncommon east to northeast flow over much of the area, which would bring some canyon winds to prone areas of the Wasatch Front. As is the case with the Washington county wind threat, the associated cold advection over northern Utah and southwest Wyoming is modest at best, keeping the chance of downslope winds low.

Beginning Thursday, high pressure will start to build off the California coast, interacting with another low near Baja California to produce a weak Rex Block pattern, bringing drier air and a slow warming trend. The block is expected to be dislodged by Saturday as a trough moves across the US/Canada border. The impacts will be minimal for Utah and southwest Wyoming, however, with dry conditions continuing with temperatures moving back to near seasonal normals.

The loss of the Pacific ridge again opens up the storm track for the potential of a more active pattern across the West beginning early next week. Despite this, there remains noticeable spread as to when a storm system might impact the area, with chances increasing beginning Tuesday. Given the level of uncertainty, details on any particular system remain dim at this time.

AVIATION, Issued 949 PM MDT Tue Oct 13 2026

KSLC...Periods of rainfall will continue through much of the overnight hours, bringing occasional MVFR conditions due to reduced visibility and lower CIGs. Northwest winds will be maintained through the overnight period, with rain showers dissipating after around 09-10Z. There is around a 30% chance that rain showers persist through the mid-morning hours.

REST OF UTAH AND SOUTHWEST WYOMING...Areas of rain showers will continue across portions of northern and southern Utah through the overnight hours, with occasional light snowfall in southwest Wyoming. For areas under rainfall, a reduction to MVFR conditions will be possible due to lower CIGs and reduced visibility, while light snowfall, low ceilings, and areas of fog will cause IFR to LIFR conditions in southwest Wyoming. Eastern Utah will become the focus for precipitation early Wednesday morning and throughout the day on Wednesday. Otherwise, light northwesterly flow is expected across a majority of terminals through the overnight hours.

FIRE WEATHER, Issued 121 PM MDT Tue Oct 13 2026

A slow moving low pressure system continues to slowly meander east across the Great Basin renewing chances for valley rainfall and high elevation snowfall (snow levels around 7000-8000ft) through Wednesday afternoon. Come Wednesday afternoon, the system looks to exit the region leaving a cool airmass in its wake. Into the weekend, a drying trend will develop with our next chances for precipitation appearing to occur Monday/Tuesday next week. On the back end of this system, canyon winds and potentially a few instances of downsloping winds look to develop Thursday night into Friday morning resulting in locally stronger gusts up to 40mph across portions of northern UT, primarily along the Wasatch Front.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Freeze Warning until 9 AM MDT Wednesday for UTZ103-115-116-118- 122.

Winter Weather Advisory until 6 AM MDT Wednesday for UTZ111-112.

WY...None.