Weather Words: Snow Squall

Just as thunderstorms can produce “squall lines” which are periods of torrential downpours and violent winds, a snow squall is basically winter's version and can be just as dangerous.

A snow squall is a sudden, intense burst of heavy snow and strong winds that can turn daylight to near-darkness in seconds. Unlike a typical steady snowfall, snow squalls are short-lived but extremely dangerous, often lasting less than an hour. They can develop when an arctic cold front sweeps through, creating narrow bands of intense snowfall, capable of dumping snow at a furious rate, sometimes more than an inch in just a few minutes.

The real danger from a snow squall isn’t all about how much snow falls, but how quickly conditions change. Visibility can drop to near zero in moments, and roads that were dry minutes earlier can become icy and slick. Drivers caught in a snow squall often have little time to react, leading to pileups and travel chaos.

The National Weather Service now issues Snow Squall Warnings to alert drivers and communities when one is imminent, similar to tornado or severe thunderstorm warnings, underscoring just how serious these sudden winter bursts can be.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.