The Great Arizona Haboob of 2011

A haboob is a giant dust storm, but a very specific type of dust storm. When a big thunderstorm collapses in a certain way, in a dry area of the world, it causes a powerful downdraft forward of the storm, in the direction the storm is moving. In a dry and dusty area, this enormous poof of wind stirs up a massive dust cloud that can be a mile high and sixty or more miles wide to run before the storm, coating everything in its path with dust. Precipitation usually evaporates in the dry heat before hitting the ground, but if the water does make it to the ground it can cause a mud storm.

What Happened in Arizona?

On July 5, 2011, a thunderstorm in the southern part of Arizona began to collapse near Tucson. This sent a downdraft out to stir the dusty desert landscape and triggered a haboob of historic proportions: at least a hundred miles wide and over a mile high, with wind gusts over 60 miles per hour, the haboob raced from Tucson up to Phoenix. Flights were grounded as visibility throughout the region dropped to zero.

The dust was so thick everywhere! You can see there were a few sprinkles of water after the dust was laid down, but just a few. In places it looked like snow drifts. Pools were clouded and muddy. Cars were trailing clouds of dust from their roofs as they drove along, and windshield wipers were industriously sloughing dust from windshields - without water, which would just have created a mudbath on the windows! Anything left outside had to be hosed down.