Dust storm warnings spread across Illinois Friday evening, including much of the Chicago area.

These advisories are issued when convectively driven dust is reducing visibilities to 1 mile or less, but greater than a quarter mile, according to the National Weather Service. Winds of 25 mph or greater are usually required.

The NWS website states a dust storm usually arrives suddenly in the form of a "wall of dust and debris" which can be miles long and thousands of feet high.

Hazardous driving conditions are created since the storms often strike with little warning prompting reduced visibility, the NWS says.

According to the NWS, dust storm warnings were in effect through much of the evening hours for several Chicago-area counties including La Salle, Will, Grundy and Kankakee counties.

The warning was extended to 8 p.m. for Kendall, northern LaSalle, northwestern Will, southern DeKalb and southeastern Cook Illinois, as well as Porter and Lake counties in northwest Indiana. It was extended to 8:30 p.m. CT over the city of Chicago.

Here are some safety tips for dust storms, according to the NWS: