Late on February 28, the snow stopped and was replaced by rain and a warm wind. Just after 1 a.m. on March 1, as a result of a lightning strike, a slab of snow broke loose from the side of Windy Mountain during a thunderstorm. A ten-foot high mass of snow, half a mile long and a quarter of a mile wide, fell toward the town. A forest fire had recently ravaged the slopes above the town, leaving very little to impede the avalanche.