A massive dust storm, also known as a haboob, engulfed Phoenix, Arizona, this week — leaving more than 120,000 without power and damaging several buildings.

"It is a huge one," KPHO reporter Jerry Ferguson reported from a helicopter. "This is a classic Arizona dust storm barreling across the southeast Valley."

Haboobs are intense sandstorms created during thunderstorms that can quickly transform the landscape into a dark, howling storm of gritty rage. The approach of a haboob is about as apocalyptic as you get.

How exactly do they form?

Haboob is an Arabic word that means "strong wind," and was first used by the American Meteorological Society (AMS) in 1972 when comparing a dust storm in Arizona to ones typically seen in Sudan. "Although much less frequent than the Sudanese haboobs," AMS wrote, "they are equally as dramatic."

Haboobs form when strong winds flow down and outward from thunderstorms and collect dust and sand in a dry, desert area like Arizona. The wind then creates a wall of dust that can spread across a large area within minutes. Some haboobs can reach heights as high as 10,000 feet and wind speeds up to 80 mph.

Even though the storms typically are short-lived, they pose a serious threat. The dust clouds can create near-zero visibility, making it virtually impossible to even see a couple feet in front of you. The winds can knock down power lines and damage buildings. The National Weather Service recommends that if you're driving when a haboob hits, pull over to the side of the road immediately.

Editor's note: This article has been updated since it was originally published in July 2011.