textproduct: Western and Central Wyoming

KEY MESSAGES

- Light to moderate snow will continue today for the western Wyoming mountains with the highest accumulations across the Tetons and southwestern Yellowstone. Western valleys will see lighter accumulations during this time. Winter travel conditions are expected over mountain roads.

- Mild and windy conditions are expected across much of southern and central Wyoming today. Southwesterly wind gusts of 40 to 50 mph can be expected through the afternoon.

- Isolated snow showers are expected across southern and central Wyoming this evening.

- A cold front will arrive Thursday. Light snow will continue across western Wyoming, with chances also spreading east of the Divide Thursday evening.

DISCUSSION

Issued at 342 AM MST Wed Jan 7 2026

The active pattern persists today with more snow for western Wyoming and wind elsewhere. Snowfall rates will be fairly steady through the day today as moisture continues to stream up the Snake River Plain within southwesterly surface flow. Accordingly, the highest amounts will again be across the Tetons and Yellowstone's Pitchstone and Madison plateaus. The Winter Weather Advisory will continue through sunset for these areas, with an additional 6 to 12 inches of accumulation. Western valleys will continue to see light snow today, with accumulations generally around an inch or less through sunset. Temperatures expected to rise into the low 30s should help to limit impacts in the valleys however, with most travel concerns expected higher up along mountain passes.

Wind is the other weather concern today given a strong west to southwesterly flow aloft and a tightened surface pressure gradient over the region. The strongest wind of the day is likely already ongoing in the Casper foothills where gusts of 60 to 70 mph have been observed through most of the night thus far. These winds should persist through mid-morning before decreasing a bit as the pressure gradient wanes slightly. At the same time, mid/upper level flow will turn more southwesterly as the next trough approaches. This will support continued wind this afternoon given mixing and the still robust surface pressure gradient aligned from the southwest to northeast. Southwest gusts of 30 to 50 mph will be fairly widespread along the Wind Corridor from southwestern Wyoming through southern Johnson County, as well as across the Winds, Absarokas, and Bighorns. Otherwise, one more day of temperatures peaking to near 50 degrees is expected east of the Divide.

Snowfall rates will decrease across western Wyoming this evening as a leading shortwave ahead of the incoming trough cuts off much of the available Pacific moisture. However, this wave and an aligned upper jet will provide a brief period of enhanced lift elsewhere. This will produce isolated snow showers after sunset today, with the best chances across southern Wyoming as well as Natrona and Johnson counties.

The main trough and cold front will arrive tomorrow. This will bring temperatures down everywhere, much closer to seasonal values. Light snow will continue across the west. Another period of light snow is expected east of the Divide as the trough axis passes through late in the day. This will be most favored for northerly upslope favored locations like Natrona County as surface flow become northerly in the evening. Accumulations here are currently expected to remain around an inch or less, though Casper Mountain and the foothills there may see a little more through Thursday night. Currently, forecast accumulations for Casper are in the 1 to 2 inch range, with Casper Mountain in the 3 to 6 inch range.

After a cold and drier Friday, ensemble guidance strongly favors the return of ridging across the western US. This would bring warmer and drier conditions to the area for the weekend, with little to no snow even across western Wyoming through at least early next week.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 404 AM MST Wed Jan 7 2026

West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals.

Persistent snow continues at KJAC. There may be a brief period of no snow around 00z/Thu, but MVFR to IFR conditions are expected to prevail through the period. If any LIFR conditions occur they would be brief, or be most likely between 15z and 23z.

Elsewhere, snow chances are much more limited, and mostly associated with an incoming cold front, with snow chances at KBPI and KPNA between about 20z and 01z, though light snow could linger past this time. For KRKS, this timeframe starts shortly after 00z, with snow then possible through the end of the period.

East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals.

Gusty west to southwest winds today. Any precipitation are too limited to mention, though there will be increasing clouds through the period. A stray snow shower could impact KCOD (15% chance) between 20z and 04z today. At KCPR, gusts 35 to 40 knots remain possible through the day, and should finally start decreasing after 00z.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts.

RIW WATCHES/WARNINGS/ADVISORIES

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