West suburban residents got a rude surprise Saturday as overnight rain left their cars dirty.Here are photos of cars after the dust fell.

So what happened that sent car owners scurrying to the car wash ?

The answer is that it was caused by strong winds blowing across hundreds of miles of terrain — including huge tracts of land being plowed as part of spring planting.

The winds sent dirt (and some pollen) airborne — and it fell, being washed from the air by Friday night’s showers.

This isn’t uncommon this time of year as farmers ready their fields for the upcoming planting season. Many areas, west and southwest of Chicago are very dry, having had a lack of winter snow and spring rains, exacerbating the problem of windblown dust.