A blizzard is a strictly defined type of storm. Not only is it a winter storm, but specifically, it a severe winter storm with sustained winds of 35mph. Snowfall accumulation is not a necessary component of a blizzard, which gives rise to the classification of “ground blizzards” which are strong storms in which visibility is reduced primarily by blowing and drifting snow caused by those strong winds.
There are two areas in which blizzards are most common: In the northern High Plains, and along the eastern Seaboard. In the Northern Plains, it is because there is little to block strong winds from gaining momentum, and similarly, along the coast there is little friction to blunt the winds coming across the open Atlantic, giving rise to “Nor’easters” named after the wind coming from the northeast.
In the Plains in particular, blizzards are often followed by very cold temperatures, thanks to the strong rotation that induced the windy conditions in the first place. Along the coast, the northeasterly winds leading to the blizzard conditions are often warmer and can stave off the plummeting temperatures, at least for a little while.
While those are the most common regions for blizzards in the United States, it should be noted that blizzards are a worldwide phenomenon, with the deadliest of all time occurring in Iran in 1972. Any time there is a violent winter time clash of cold air and warmer moister air, creating a deep area of low pressure, a blizzard could be possible. 3