6 Dead After Illinois Dust Storm Causes Crashes on Interstate 55 - The New York Times:

The dust storm came on rapidly, creating conditions similar to a snowstorm whiteout, in which visibility is greatly reduced, the authorities said.

Although dust storms can occur anywhere in the United States, they are most common in the Southwest, according to the National Weather Service. They rarely occur in central Illinois, Ben Deubelbeiss, a meteorologist with the service, said.

But a dry spell, combined with very strong winds, had created Monday’s conditions, Mr. Deubelbeiss added, noting that the Springfield airport — about 30 miles north of the crash site — had recorded just half of its usual rainfall for the month of April. Wind gusts at the airport were blowing up to 40 miles per hour on Monday, he added.

I will note once again—and not for the last time either, I am sure—that we are likely going to need to rapidly reassess our use of the word “rare” for stuff like this.