What's up with that Brownish Red Mud?

What's Up With That Brownish Red Mud That Is All Over My Car?

The picture below indicates the areas of dust/sand across the Arizona desert and shows what the transporting wind flow was.  The result of the dust/sand and the transporting wind plus the additional ingredient of moisture (wet or frozen) is  explained below the picture.
No, it apparently was not from Iceland, China, or Mars.  It was an invasion of dust and small sand particles courtesy of the Arizona desert.  Strong southwesterly surface winds and winds in the upper atmosphere associated with the jet stream, had picked up the surface layer of dust and sand particles from the Arizona desert and transported these particulants northeastward into and across northwest New Mexico and the southern parts of Colorado.  The dust and sand particles reduced the visibilities to under 4 miles in areas of Arizona, New Mexico and Colorado.  The pollutants then continued their journey northeastward and moved over northeast Colorado which included Metro Denver and adjoining communities.  A pilot report indicated that the dust/sand had reached altitudes of 37,000 feet.  As this reddish brown phenomena moved northeastward, it came into contact with rainfall and snowfall which attached itself to the dust and sand and together they fell to the gound.  Wherever the combination of liquid, dust and/or sand made contact, the outcome was a reddish brown mess that looked like liquid dust or in some places, liquid mud.  This type situation only occurs if there is a strong southwest wind from the surface to the upper atmospheric wind levels and the desert surface is extremely dry.  That combination must then combine with some form of liquid (rain and/or snow) which will then fall from the sky and create that reddish brown concoction that ruined the look of your newly washed vehicle or the clothes that you just hung out to dry.


Courtesy of the Denver/Boulder National Weather Service Forecast Office


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