7/7/2011 2:01:00 PM 'Haboob' brings dust to Verde Valley
VERDE VALLEY - The National Weather Service in Bellemont says the thick dusty haze that Verde Valley residents saw blanket the Verde Valley Wednesday and Thursday morning is a remnant of the huge haboob dust storm that swallowed up the Phoenix area in a dramatic fashion Tuesday afternoon.
While not uncommon in the desert southwest, this haboob, estimated at two miles tall and 60 miles from end to end was massive and moved northwest, eventually carrying fine dust through the Verde Valley.
According to sources cited by Wikipedia, the arid and semiarid regions of North America may experience haboobs, an Arabic word meaning strong storm.
"During thunderstorm formation, winds move in a direction opposite to the storm's travel, and they will move from all directions into the thunderstorm. When the storm collapses and begins to release precipitation, wind directions reverse, gusting outward from the storm and generally gusting the strongest in the direction of the storm's travel."
When this downdraft, or downburst, reaches the ground, dry, loose sand from the desert settings is essentially blown up, creating a wall of sediment preceding the storm cloud.
Eye and respiratory system protections are advised for anyone who must be outside during a haboob and it is suggested to move to a shelter during a strong event. Phoenix area residents were warned that the fine dust that accumulates in the lungs can be a cause of Valley Fever.