Riverton, Wyoming – Drivers on U.S. 26 near Riverton should prepare for thunderstorm activity starting Saturday afternoon, with gusty winds and hail possible through Memorial Day. The National Weather Service warns that weekend travel plans across western and central Wyoming could be disrupted as a spring storm system sweeps through the region.
According to the National Weather Service in Riverton, scattered showers and thunderstorms will begin developing after 2 p.m. Saturday, with strong wind gusts and small hail likely in localized areas. Showers will intensify by evening, especially across Natrona, Fremont, and Sweetwater counties, continuing into Sunday.
Saturday night into Sunday, expect steadier rainfall and embedded thunderstorms with clearing delays into Monday. Riverton, Lander, and Casper could see prolonged periods of rain that impact outdoor events. The primary risks include lightning, ponding on roads, and sudden gusts along highways such as U.S. 20 and WY-789.
Memorial Day will be mostly sunny but still carries a slight chance of afternoon thunderstorms. Anyone attending outdoor celebrations should monitor the sky and seek shelter quickly if thunder is heard.
Looking ahead, a warming trend brings daily chances of afternoon showers through Thursday. Highs will climb from the mid-70s on Monday to over 80°F by Thursday. Calm mornings will give way to unstable afternoons—a classic summer pattern returning to the region.
