Desert tempest - Window on the West - causes of monsoons in Arizona - online information from Arizona Thunderstorm Chase Project - Brief Article

Sunset, August, 2003 by Tim Vanderpool

"Monsoon comes from the Arabic mausim, meaning "wind shift." But don't let this gentle term fool you--Arizona's monsoon thunderstorms are earth-pounding tempests. They occur from July to September, when changing airstreams draw moisture-laden currents from Mexico tot he dry Southwest, where they collide with hot desert updrafts. The result: flashes of lightning, thunderous eruptions tumbling across the sky, gusts up to 115 mph, and half of the year's rainfall. Despite their destructive potential, monsoon thunderstorms spark a primal fascination in desert dwellers. In homes and offices, people gather to watch as one of nature's grand melodramas washes away the summer heat.

Visit geography.asu.edu/aztc/mansoon.html for monsoon information from the Arizona Thunderstorm Chase Project. If you're in Tucson, a prime monsoon-watching spot is on the upper floors of the University of Arizona Main Library (520/621-6441)