What is a snow squall?

 After Wednesday night's brief snow showers, some may be seeing the term "snow squall" tossed around social media. That begs the question: what is a snow squall? It is a short-lived, but intense snow shower that can bring whiteout conditions and a quick coating of snow on roadways and untreated surfaces. Given the sudden onset and intensity of snow squalls, they can cause hazardous if not dangerous travel in the narrow areas they impact.

Rockford saw a couple brief, but intense snow showers Wednesday night, coating untreated roads and dropping visibility below 2 miles at times. Here is a perfect view of the limited visibility in downtown Rockford as one of those snow showers moved through.

These snow squalls are typically limited in coverage, as shown well from this radar image taken from Wednesday evening. A narrow band of snow showers was stretching from Madison, WI to just North of Chicago, while a second band was stretching from Rockford to Aurora.

Those narrow bands of snow provided a coating of snow where those squalls passed through, as seen with visible satellite under the otherwise sunny sky from Thursday morning. This is a good example of how limited the coverage of snow was. Some saw a coating of snow, while many saw no snow at all.

Some of the most intense snow squalls can trigger snow squall warnings from the National Weather Service. Think of these to be like severe thunderstorm warnings, but with snow. Some of them can trigger EAS alerts on your phones when they cause extremely dangerous travel. Snow squall warnings are very rare, though. Rockford has only ever seen two snow squall warnings issued, both on February 18th, 2022. Meanwhile the entire National Weather Service forecast area centered in Chicago has only issued them on three dates, including yesterday. In total, only 7 snow squall warnings have even been issued by NWS Chicago. When you see a snow squall warning, be sure to take heed of any travel advisories associated with them!