What is it?

A blizzard is the worst kind of snowstorm, in which strong winds blow snow into snowdrifts (huge piles) that can bury people and possessions. Its official definition is a tempestuous, frigid snow storm with blustery, piercing winds of 35 miles per hour or more and a windchill factor as low as -20º Fahrenheit. Transportation is difficult and dangerous during blizzards because air temperatures can be 10ºF or lower, with visibility less than 400-500 feet.