Blizzards are dangerous because of freezing temperatures that are exacerbated by high wind, difficulties getting through heavy snow and the possibility of getting lost in blinding flurries. A person caught outside in a blizzard needs to seek shelter immediately.
The National Weather Service defines blizzards as storms with winds over 35 mph, heavy snow or blowing snow on the ground and visibilities of less than one-fourth of a mile for at least three hours. In conditions like this, it's easy to get lost. For people in a stranded vehicle or caught outside, hypothermia can be deadly. Road conditions are dangerous due to the combination of slick surfaces, high winds and poor visibility. Wind and snow may also take down power lines, putting people at risk of hypothermia in their own homes.