I was sitting in an airplane on the runway, waiting to take off, when I saw this unexpected sight out my window!
It’s called a “haboob”!
The definition I found to explain this strange phenomenon is this: A haboob (Arabic: هَبوب “blasting/drafting”) is a type of intense dust storm carried on an atmospheric gravity current. Haboobs occur regularly in arid regions …
It would appear that Phoenix AZ classifies as one of those arid regions!
And it was certainly something unexpected, that’s for sure!