Crews are cleaning up downed trees and have mostly restored power after a powerful dust storm hit the Phoenix area.

On July 5, 2011, a dust storm grew to 100 miles wide and more than 1 mile high, and dumped 40,000 tons of dust on Phoenix in just two hours. Clean up took days.

The weather phenomenon forms when intense winds from a thunderstorm rush outward, creating a thick wall of dust.

Phoenix hit by major dust storm Monday, leaving thousands without power and temporarily halting airport operations across the metro area.

A summer storm followed a dust storm that created a shocking scene. What you should know.

One mother told how the dust storm affected visibility so much she could not see her hand in front of her face.