textproduct: Western and Central Wyoming

KEY MESSAGES

- Dry and warm conditions continue through Monday. A breezy southwest wind will be seen for portions of central Wyoming through this period.

- Rain and snow chances increase across western Wyoming beginning Tuesday. An associated cold front will bring snow levels down to western valleys Tuesday evening, though most of the accumulation is expected to remain in the mountains.

- Cooler, more seasonable temperatures are expected beginning Wednesday. There are hints of the next system arriving Thursday, bringing additional precipitation chances to all areas through the end of the week.

DISCUSSION

Issued at 341 AM MST Sun Nov 15 2026

Warm and dry conditions are expected over the next 48 hours as ridging returns to Wyoming. While not quite as warm as yesterday, temperatures will peak 6 to 10 degrees above normal today. This will make for a fairly pleasant Sunday, albeit with a gusty southwest wind from Farson through Natrona County induced by a pressure gradient set up across the state. On Monday midlevel flow becomes southwesterly as we enter the backside of the ridge ahead of the next trough. Not much will change, though temperatures will increase slightly for most locations.

The trough will approach Tuesday as an open wave. Most guidance has this digging south into the Great Basin and splitting somewhat as it pulls northward into the Rockies. Combined with only modest moisture, this does not favor a particularly noteworthy precipitation event. Regardless, this will return chances to western Wyoming beginning Tuesday morning, spreading eastward through Tuesday night. Locations east of the Divide can expect another warm and windy day ahead of an associated cold front. This front will bring snow levels down across western Wyoming, likely to the valleys Tuesday night. Currently total liquid amounts are under a half inch across the western mountains, with less forecast in the valleys. Forecast snow totals in the mountains are in the 3 to 5 inch range, focused mostly across the Tetons, Gros Ventres, and western Wind River Range. The best chance for precipitation (rain) east of the Divide will be Tuesday night, though most areas are expected to remain dry.

Precipitation is largely expected to end by Wednesday afternoon. A cooler airmass will be in place, with temperatures peaking around more seasonable values. Most models have the next system following quickly, with precipitation returning to western Wyoming beginning Thursday. This next system appears to progress similarly to the former, though perhaps a little stronger in magnitude. The current forecast reflects this, with more widespread precipitation chances for the area from Thursday evening through Saturday morning. With the colder air in place, this could bring light snow to the basins on both sides of the Divide. While uncertainty in the progression and strength of this system is high, continued cooler and unsettled weather appears likely through the end of the week.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 405 AM MST Sun Nov 15 2026

Low clouds/fog remains possible (15%) around KBPI and KPNA through about 16z. Low clouds are also around KCPR through about 15z. Once these clouds dissipate, VFR conditions are expected at all sites through the period. Afternoon winds will be strongest at KCPR, with gusts around 30 knots. High clouds pass over the area today, with FEW to BKN clouds generally above 12000 feet AGL.

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

None.