HABOOB
The name comes from the Arabic word habb, meaning "wind." A Haboob is a giant wall of dust sometimes 3000ft tall,that travels a 40mph+, they frequently form here in Arizona from the gust front outflow boundary of summer thunderstorms. Haboobs are most frequent in Southwestern North America during the months of May through September, with the most frequent occurrence in late June, but they can occur in every month. (A picture of a classic Haboob appears on our Monsoon Page.)