textproduct: Western and Central Wyoming

KEY MESSAGES

- A weather system brings accumulating snow to the western mountains overnight into Monday. Winter driving conditions are expected across Teton Pass and Togwotee Pass beginning in the early AM hours Monday.

- Light rain is possible Monday for lower elevations east of the Continental Divide. The best chances (20-40%) will be across the Bighorn Basin and Johnson County.

- Elevated fire weather conditions are expected across much of central and southern Wyoming Monday due to above normal temperatures, gusty winds, and mostly dry conditions.

- An active weather pattern will persist through most of next week, leading to cooler temperatures and several chances for precipitation, especially in the mountains.

UPDATE

Issued at 248 PM MST Sun Feb 8 2026

Only minor changes to the forecast were made with this update. Snow accumulations as discussed below are largely on track, though have decreased slightly over central and northern portions of Yellowstone National Park. The heaviest period of snowfall will be from around midnight tonight through mid-Monday morning as moisture and southwesterly flow is maximized ahead of the trailing cold front. Otherwise, most of the area will see elevated winds tonight, most notably along South Pass (70% chance of gusts over 60 mph) and southern Casper (80% chance of gusts over 50 mph).

DISCUSSION

Issued at 237 AM MST Sun Feb 8 2026

09Z satellite water vapor imagery shows flow aloft becoming more zonal over western Wyoming while northwesterly flow remains over the rest of the area. The zonal flow is ushering Pacific moisture into the area, evident by increased cloud cover, and will bring the return of winter to the west as early as late morning today/Sunday. The strongest winds aloft, and associated moisture, will be focused over Montana and northwestern Wyoming much of the daylight hours today. A weak embedded disturbance is forecast to sweep over northwestern portions early this afternoon and bring light snow chances mainly to Yellowstone National Park. There is a 90% chance that snow amounts during the daylight hours will be less than 0.5 inches across the highest terrain of Yellowstone.

The real show for the west begins around sunset today. By 00Z/5PM today, flow across the entire state becomes zonal and allows most of western Wyoming to fully tap into the aforementioned Pacific moisture. With the available moisture and embedded shortwaves traversing the area, snow chances across the west will quickly ramp up after sunset and persist through most of the day on Monday. The greatest snow amounts are expected across Yellowstone National Park and the Teton and Gros Ventre Mountains. From 5PM Sunday through 5PM Monday there is 90% chance of at least 6 inches of snow and 50% of at least 9 inches. Given these high probabilities and gusty 20 mph to 35 mph gusty winds due to a tightening pressure gradient, a Winter Weather Advisory has been issued for these areas beginning 5PM today/Sunday until 5PM Monday. The highest elevations of the Tetons and Yellowstone could see 15 to 18 inches of snow during this time period, but due to widespread amounts below 12 inches and given that Teton and Togwotee Passes are forecast to see up to 8 inches (60% chance), opted with only an advisory. The highest snowfall accumulations are forecast to occur between 11PM Sunday and 11AM Monday along and behind a cold front. Only light accumulations of 1 to 2 inches (20%-60% chance) are expected for Jackson Hole Valley and Star Valley.

While western Wyoming will see snow, the rest of the forecast area will see gusty winds and possible elevated fire weather conditions, especially on Monday. Flow aloft today/Sunday will generally be northwesterly through early afternoon before becoming zonal with weak disturbances traversing overhead. By early afternoon, 700 mb 30kt to 40kt 700mb develop across the Absarokas, the eastern Wind River Mountains, and from South Pass to southern Johnson County. With deep mixing expected across these areas, especially the southern half of Johnson County, there is a 80%-90%+ chance of 30 mph to 40 mph wind gusts this afternoon and tonight across these areas. By Monday morning, the surface pressure gradient begins to tighten ahead of the approaching cold front. This will bring widespread gusty 20 mph to 40 mph winds to most the area. Elevated fire weather conditions are possible both days, especially on Monday, as a result of gusty winds, temperatures both days remaining 20 to 30 degrees above normal, and relatively dry conditions across southern Wyoming and east of the Continental Divide.

By Monday evening, the main shortwave and associated cold front makes its way east and brings isolated precipitation chances (10%- 30%) to the rest of the area. 700mb temperatures ahead of the front are forecast to range from +1C to +5C and quickly fall behind the front to -5C to -10C by Monday night. This means that any precipitation east of the Divide will likely first fall as light rain and transition to light snow.

There is good consensus among model guidance that cooler, albeit still above normal, temperatures will grip the state Tuesday through at least Friday. There is also good consensus that more widespread snow chances (20%-70%) exist Tuesday through late Wednesday. These snow chances are associated with a Tuesday disturbance preceding a more potent shortwave and front traversing the state on Wednesday. The current forecast reflects relatively light snow amounts across the area, with a light dusting for low elevations to up to 7 inches for the western mountains. Nonetheless, any amount of moisture is welcome as this has been a relatively dry winter thus far.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1000 PM MST Sun Feb 8 2026

Satellite imagery shows clouds streaming into the region ahead of the next weather system. Expect periods of MVFR conditions at many airports across western and central Wyoming, and even periods of IFR conditions, especially west of the Divide where valleys will see periods of light to moderate snow during the day Monday. Mountain snow will be more robust, with the high terrain obscured for much of the next 24 hours.

KCPR is one site east of the Divide that is more likely (80% chance) to see a few hours of snow and visibility impacts after winds shift to northerly around sunset Monday.

Other than snow, wind will also be a concern for aviators. A front will move through the region, and gusts in the 25 to 40 kt range will be common throughout the daylight hours. A shift to northerly winds will occur for basin locations east of the divide, so it's worth paying attention to the timing of that shift at your airport of interest.

RIW WATCHES/WARNINGS/ADVISORIES

Winter Weather Advisory until 5 PM MST Monday for WYZ001-012.