Brent McRoberts of Texas A&M University answers your weather questions. This week’s edition: blizzards.
Q: How strong does a snowstorm have to be before it’s called a blizzard?
A: There are some specifics regarding blizzards, says McRoberts. “In meteorological terms, a blizzard is a severe storm that has below-freezing temperatures, winds of at least 35 miles per hour and heavy snowfall, with visibility reduced to just 1/4 of a mile, and all of these conditions have to last at least three hours,” he explains. “So just a heavy snowfall is not always a blizzard. Blizzard conditions occur most often in the Great Plains, North Central United States and parts of the Northeast.”
Q: What are some of the country’s worst blizzards?
A: The blizzard that hit the Northeast in recent days may well wind up in the record books, he notes, as it shut down Washington, D.C., Baltimore and other cities, and final snow totals are still being recorded. In previous years, Buffalo had a blizzard that paralyzed the city for days in 1999, Colorado had a similar situation in 1997 and Boston suffered terrible blizzard conditions in 1978, McRoberts says. “Chicago had devastating blizzards in 1979 and one in 1967,” he adds. “The ’67 blizzard totaled 23 inches of snow with drifts up to 9 feet and the city was virtually shut down for days, with the Department of Streets and Sanitation estimating that about 75 million tons of snow fell. At least 60 people died, many of them from heart attacks while shoveling snow. Although records tend to be sketchy, perhaps the country’s worst blizzard occurred in 1888. In parts of the Midwest, the temperature fell from 74 degrees to minus 28 within hours, and the Colorado River froze solid throughout much of Texas. That blizzard claimed 235 lives.”
Weather Whys is a service of the Department of Atmospheric Sciences at Texas A&M University