RIVERTON, Wyo. – Western Wyoming woke up to freezing temperatures Tuesday, with frost and dense fog affecting drivers across key mountain valleys. The National Weather Service has issued a Freeze Warning until 10 a.m., urging residents to protect plants, pets, and sensitive plumbing.
According to the National Weather Service office in Riverton, fog is likely to linger across Yellowstone National Park and southern Lincoln County through mid-morning Tuesday, creating slick conditions on roads including US-26 near Riverton and stretches of I-80 west of Rock Springs. Motorists are advised to allow extra travel time and keep headlights on in reduced visibility.
Conditions will improve by Wednesday as skies turn sunny and highs climb into the mid-70s across Riverton, Casper, and Jackson. By Thursday, September 25, afternoon highs could reach near 79 degrees, offering a short-lived return to pleasant fall weather. Winds will remain light, though valleys could still see patchy morning fog.
Looking into the weekend, temperatures will hold steady in the upper 70s to low 80s during the day, with clear, cool nights dipping into the low 40s. While frost risks diminish after Tuesday, another round of scattered thunderstorms is possible Sunday and Monday across southern Wyoming.
Residents should stay alert for updated advisories, especially with the season’s first hints of winter weather already brushing the state.
Five-Day Forecast for Riverton, Wyoming
- Tuesday: High 68°F, patchy fog early, then sunny. Low 40°F.
- Wednesday: Sunny, high 75°F. Low 41°F.
- Thursday, September 25: Sunny, high 79°F. Low 43°F.
- Friday: Sunny, high 80°F. Low 42°F.
- Saturday: Sunny, high 79°F. Low 44°F.
