WHAT: A roiling wall of sand and dust up to a mile high and moving at speeds up to 60 miles per hour.
WHERE: Mainly in North Africa, Australia, the Middle East, and the U.S. Southwest.
HOW: As a thunderstorm dies, dry downdrafts up to 100 mph hurtle loose sand and dust
into the air.
SUPERFREAKS: In January 2013, Australian tugboat workers near the coastal town of Onslow snapped cell-phone photos of a Creamsicle-colored haboob, a 50-mph orange monster that merged with a billowing white shelf cloud and swept over the Indian Ocean at sunset.
THE FORECAST: “Most studies indicate drier conditions in the Southwest over the coming decades,” says Arizona State University geographical sciences professor Randy Cerveny. “That would likely mean drier thunderstorms and more haboobs.”