When is a Winter Storm Considered a Blizzard?

February 11, 2021 // Article by: Mike Mihalik

Over the years, the term "blizzard" as been used fairly loosely by many. For the Mid-Atlantic and Northeast, it seems as though any time a coastal storm drops over a foot, some like to call it the "Blizzard of (insert date here)". In reality, the amount of snow that accumulates doesn't factor into whether a storm is deemed a blizzard. So what constitues a blizzard? The National Weather Service defines it as, "Sustained wind or frequent gusts to 35 mph or more, accompanied by falling and/or blowing snow which frequently reduces visibility to less than 1/4 mile for three or more hours."

Meteosat-3 Infrared Satellite image of the 93 Superstorm. Notice the textbook "comma" shape, indicating an intense low pressure system. Courtesy https://cimss.ssec.wisc.edu/satellite-blog/archives/12481

So really, snow doesn't even have to be falling for blizzard criteria to be met! Blowing snow from the ground can be enough if winds surpass thresholds and visibility is low enough for the three-plus hour duration. Even though ground blizzards can happen, snow fallingly heavily certainly helps to acheive the lofty status. So what are some memorable storms that reached blizzard conditions? Well the "Superstorm of 93" met the criteria in many places as heavy snow and gusty winds flew from north Georgia through northern New England. Speaking of New England, the Blizzard of '78 did the job with extreme winds...gusts of 85 - 100 mph! The February 2013 winter storm, dubbed "Nemo", also reached blizzard conditions in spots, which included 4"+ per hour snowfall rates in portions of Connecticut. Interestingly,"The Blizzard of '96", only had around two observing sites that reached blizzard criteria (regardless of the 24+ inches of widespread snow). Those stations were Trenton-Mercer Airport and Morristown Municipal Airport in New Jersey. 

So next time you are hearing about a blizzard, be sure to check the definition, because the wind and visibility thresholds are a bit harder to hit than you think!