textproduct: Western and Central Wyoming

KEY MESSAGES

- The remainder of today is dry and cold, with highs in the upper teens to low 20s for most of the area.

- A weak weather system brings light snow to western and southern Wyoming Sunday. Most of that area should see an inch or less, with isolated areas up to 2 inches. Southern Lincoln County could see up to about 3 inches.

- Multiple weak weather systems are expected through the coming week, bringing light snow chances and keeping temperatures cool to seasonal.

UPDATE

Issued at 1108 AM MST Sat Nov 29 2025

With snow moving out of the area, the rest of today remains dry. Current satellite shows most of the area in white, though southwest Wyoming remains brown (no snow). This should change tomorrow as a weak system brings snow chances across western and southern Wyoming. Latest models have west of Divide locations generally seeing an inch or less, with isolated areas closer to 1.5 inches where heavier snow showers occur. Highest totals are expected over the Salt/Wyoming Ranges (2 to 4 inches) and into the lower elevations of southern Lincoln County (1 to 3 inches). Isolated areas close to 4 inches could also occur (20 percent chances).

Sunday afternoon, some gusty north-northeast winds, 25 to 30 mph, occur over I-80. With snow chances, this could cause some minor winter travel conditions through the evening.

DISCUSSION

Issued at 217 AM MST Sat Nov 29 2025

Winter has finally arrived and punched many locations in the mouth Friday night. It was rather nasty when I arrived for my shift; snow with wind gusts close to 50 mph. As I write this before 2 am, snow is still ongoing across portions of the area, mainly the eastern portions. We should see the worst of this through around 3 am, with improving conditions following that as the front continues to move south away from the area. All snow should be over by sunrise, if not before. As for wind, it continues to be quite strong, especially in the northwest flow locations. Buffalo and Greybull are continuing to have gusts to around 50 mph, although they are decreasing elsewhere. We may be able to cancel the Advisories somewhat early, if the wind decreases a bit earlier than expected.

The main story today will be the cold temperatures, the coldest so far this season. This will especially be the case in areas that saw some accumulating snow, adding the assist from the fresh snow increasing the albedo and the weak late November sun having a limited effect. Most locations will stay in the 20s and some areas in the teens. Tonight will be the coldest night of the season for many, especially east of the Divide where most areas have at least a 1 in 2 chance of lows falling into the single digits. Increasing high clouds late tonight should keep most locations above zero though.

The aforementioned clouds will be coming from the next wave that will largely impact southern and southwestern Wyoming, as it drops in from Idaho. This wave is also a fast mover and has even less moisture to work with than last nights wave, and the best dynamics remain to the south and west of Wyoming. Probabilistic guidance shows even less snow than yesterday. The only location with a greater than 1 in 2 chance of 2 inches or more are the Salt and Wyoming Ranges, with only a 1 in 4 chance of 4 inches. The lower elevations from Afton through Rock Springs have around 1 in 3 chance of an inch or so of snow. As for east of the Divide, a few showers may jump the Divide, but any amounts should minuscule. All snow from this system should end by midnight Sunday night.

Transitory ridging should bring a dry and somewhat warmer day for Monday. The next system then drops in on our fast moving northwest flow for Monday night and Tuesday. There continues to be some model disagreement on the details of the system, but there is greater than a 1 in 2 chance of some locations getting some snow from this system, although probabilistic guidance also shows there is less than a 1 in 4 chance anywhere in the lower elevations of 3 inches or more, so right now it is not looking like a major storm. Another wave may approach for the end of the week, but details are impossible to determine this far out. Temperatures look to moderate to near normal to slightly below normal through much of next week.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1018 AM MST Sat Nov 29 2025

The last of the low clouds from overnight snow has eroded in the past hour, with only high cirrus drifting overhead across the state. This cirrus will continue to increase as the next weather system sweeps in overnight tonight. Cloud cover will increase and lower through the night for sites west of the Divide, reaching low MVFR/IFR levels by tomorrow morning. Have not yet added precip to these sites, as this may not occur until 18Z/30.

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

RIW WATCHES/WARNINGS/ADVISORIES

None.