|October 17, 2011 haboob in Lubbock, Texas|
as printed in the Washington Post
Probably the best video I've ever found on haboobs is this one from the July 5th, 2011, haboob in Phoenix. This Phoenix haboob was produced by downdrafts associated with a monsoon thunderstorm. As with Texas, Phoenix has been in a drought and so there was enough dust to make the haboob exceptionally intense.
Haboob is an Arabic word for "strong wind."