The definition from the National Weather Service is clear enough. "A snow squall is an intense short-lived burst of heavy snowfall that leads to a quick reduction in visibilities and is often accompanied by gusty winds." But this time-lapse video, or this one from NBC News might do the term better justice. They show Wednesday's squall blanketing New York City. And New York wasn't the only region hit with awful driving conditions and frigid temperatures—two people were killed and dozens injured in a series of accidents on Interstate 80 about 150 miles northwest of Philadelphia, reports USA Today.
"The loss of heat on the road due to the heavy snow can cause (the road) to quickly drop below freezing," explains an AccuWeather meteorologist. "This is a particularly dangerous threat that snow squalls can often pose." The wintry weather—which arrived days before the official start of winter—included the "gusty winds" mentioned in the NWS definition of a squall. In Boston, for example, the wind chill was minus 3 degrees. (Meanwhile on the other side of the globe...)