Haboobs are dust storms caused by strong winds flowing downward and outward from thunderstorms.
All thunderstorms produce these gusty winds, so for a haboob to form, the storm needs to be in a location where the winds can pick up small particles of dirt or sand in a dry desert area.
Outflow winds flowing downward and outward from thunderstorms can cause haboobs by kicking up dust in dry desert areas.
According to severe weather expert Dr. Greg Forbes of The Weather Channel, upward motion on the leading edge of the gusty winds and turbulent motions within the strong winds stirs up the dust into a layer several thousand feet thick. This then creates images of huge walls of dust in the southwestern United States, particularly Arizona.
Haboobs are a big danger for motorists. Visibility can be reduced to near zero in a matter of seconds, resulting in the potential for deadly highway accidents. The strong thunderstorm winds that cause haboobs can also cause tree damage and knock out power.
Due to the hazards produced by haboobs, the National Weather Service issues dust storm advisories and dust storm warnings to warn the public when one is in progress.
The National Weather Service recommends that you pull off to the side of the road immediately if you encounter a dust storm. After doing so, place your vehicle in PARK, turn headlights and taillights off, and take your foot off the brake. This is because other vehicles may try to follow taillights in a dust storm to get through it, causing them to potentially crash into your vehicle from behind.
The word haboob comes from parts of the world where dust storms are common: the Middle East and northern Africa. According to the American Meteorological Society glossary, the term is derived from the Arabic word habb, which means wind.
Photos: June 2012 Haboob in Arizona
The sky turned orange in Scottsdale, Ariz. during the Haboob. iWitness/Mikelp82