An incoming blast of winter in October has prompted the National Weather Service to issue a winter storm warning and winter weather advisories for most of East Idaho.
The storm barreling through from Canada is forecast to begin dumping snow early Monday morning on East Idaho, with the first flakes falling on the Island Park, Spencer, Dubois and Kilgore areas, where the winter storm warning is in effect. By Monday evening, snow could be falling on the entire region.
Winter weather advisories have been issued for most of East Idaho, including the Pocatello, Chubbuck, Blackfoot, Idaho Falls, Ammon and Rexburg areas.
The storm is forecast to bring snow as well as rain to East Idaho through Tuesday morning, though the precipitation might linger for longer in some places, the weather service said.
For most of East Idaho, the storm is expected to provide the first measurable amounts of snow of the 2021-22 winter season, though it's technically still autumn.
The hardest hit areas will be Island Park, Kilgore, Spencer and Dubois, where 2 to 6 inches of snow will fall in the valleys and up to 20 inches in the higher mountains, the weather service said. Driving conditions in these areas are expected to become hazardous because of the snow and temporary road closures are possible, the weather service said.
"If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency," the weather service said.
Higher elevations throughout the rest of East Idaho, including the Victor, Palisades, Swan Valley, Almo, Arbon, Rockland, Malta, Holbrook, Albion, Lava Hot Springs, McCammon, Arimo, Downey, Inkom, Bone, Soda Springs and Montpelier areas, could receive 2 to 6 inches of snow in the valleys and up to a foot in the higher mountains.
East Idaho's lower elevations including the Pocatello, Chubbuck, American Falls, Aberdeen, Blackfoot, Fort Hall, Shelley, Firth, Idaho Falls, Mud Lake, Craters of the Moon, Idaho National Laboratory, Ammon, Rigby and Rexburg areas could receive 1 to 4 inches of snow with possibly more in the higher elevations around Pocatello.
Periods of rain will also occur during the storm, especially in the lower elevations.
Winds of up to 45 mph will hit East Idaho as part of the incoming weather system, causing blowing and drifting snow in many areas.
Daytime high temperatures in most of East Idaho will be in the 40s on Monday and Tuesday, while nighttime lows will likely dip below freezing even in the lowlands during the storm.
Elsewhere in the state, the storm has triggered a winter weather advisory calling for several inches of snow in the Sun Valley, Ketchum, Hailey, Stanley, Challis, Arco, Mackay and Salmon areas.
Outside of Idaho, there are hazardous weather alerts, winter weather advisories, winter storm watches and/or winter storm warnings in Nevada, Utah, Wyoming and Montana because of the storm.
Stay with idahostatejournal.com for the latest weather forecast updates.