Not all dust storms are created equal. And this recent dust storm near Phoenix was so big it enveloped a city in dust and sand.

RELATED: Storm Shield app provides life-saving weather alerts
RELATED: RadarCast can tell you when it's about to rain at your location

Dust storms are a common sight during the Southwest United States' monsoon.

They form when winds from thunderstorms pick up sand, dust and dirt, forming a wall of dust and dropping visibility to near zero.

Follow Storm Shield Meteorologist Jason Meyers via the Storm Shield app on Twitter, Facebook, and YouTube. Download the Storm Shield Weather Radio App for your iPhone or Android device and get severe weather alerts wherever you are. Named by Time.com one of the best weather apps for your iPhone.