Winter snowstorm headed to eastern Idaho Wednesday Updated at Share This IDAHO FALLS – A winter storm is headed towards eastern Idaho Wednesday morning. The National Weather Service in Pocatello is forecasting “wet and heavy snow for at least 48 hours.” The areas of impact extend from Stanley and Ketchum to Jackson and from West Yellowstone to Twin Falls and Montpelier. The areas of Blackfoot and Pocatello are not included. The Central Idaho Mountains in Blaine, Butte, Camas, Custer, and Lemhi Counties are expected to get the heaviest snowfall from Wednesday morning to Thursday night. Anywhere between eight and 20 inches is possible, the NWS says, with strong winds causing blowing and drifting snow on the roads.