Weather
Idaho Winter Weather Awareness Week Oct 25-31: Know the Blizzard Signs
Boise, ID – Winter Weather Awareness Week begins Sunday, October 25, with an important question for Idaho residents: What actually makes a winter storm a blizzard? From the Snake River Plain to the st
By Natalie Rhodes · 2026-10-25T17:49:03.735Z
Boise, ID – Winter Weather Awareness Week begins Sunday, October 25, with an important question for Idaho residents: What actually makes a winter storm a blizzard? From the Snake River Plain to the state's mountain passes, strong winds and blowing snow can turn a routine drive into a dangerous situation.
According to the National Weather Service NWS , a blizzard occurs when sustained winds or frequent gusts reach at least 35 mph, accompanied by falling or blowing snow that reduces visibility to one quarter mile or less for at least three hours.
Heavy snowfall isn't required. Strong winds can lift snow already on the ground, producing a ground blizzard even after new snowfall stops.
What's the Difference Between a Watch and a Warning? A Winter Storm Watch means significant winter weather is possible, giving residents time to prepare.
A Winter Storm Warning means dangerous winter conditions are expected or already occurring.
A Blizzard Warning indicates blizzard conditions are expected or underway. Travel can become extremely dangerous as visibility drops and snowdrifts block roads.
What Should Idaho Residents Have Ready? Before winter storms arrive, households should prepare emergency supplies, including:
Food and water: At least three days of nonperishable food and one gallon of water per person daily. Warmth: Extra blankets, sleeping bags, insulated clothing and safe backup heating options. Emergency supplies: Flashlights, batteries, medications, first aid kits and charged power banks. Vehicles: A full gas tank, blankets, jumper cables, an ice scraper, a small shovel and emergency supplies. Snow removal: Shovels, ice melt, rock salt and traction materials. Never operate generators, outdoor grills or other outdoor fuel burning equipment indoors or inside garages because of deadly carbon monoxide risks.
Why It Matters Across Idaho From Boise and Ada County to Twin Falls, Pocatello, Idaho Falls, Coeur d'Alene and Sandpoint, winter storms can disrupt travel across Idaho.
The Snake River Plain is especially vulnerable to blowing and drifting snow. Strong winds across open terrain can sharply reduce visibility along Interstate 84 and Interstate 86.
In eastern Idaho, Interstate 15 and U.S. Highway 20 can become hazardous during snowstorms, particularly across exposed stretches near Idaho Falls and Rexburg.
Northern Idaho and the central mountains face heavy snowfall, icy passes and rapidly changing conditions along Interstate 90 and mountain highways.
Remote roads, extreme cold and long distances between services can make stranded vehicles particularly dangerous.
As Winter Weather Awareness Week continues through Saturday, October 31, residents are encouraged to review emergency plans, check supplies and monitor official NWS forecasts and Idaho 511 road conditions.
Remember: A blizzard is defined by wind, visibility and duration — not snowfall totals.