"Just ash with rain? Not so fast"

The mud rain we got on Tuesday might have been good for car washes and annoying to the average Joe, but it seems to be generating some fun for scientists.

From Graeme Zielinski of the Express-News:

"This is very enjoyable," said Joel Gilbert, a University of Texas at El Paso geological sciences coordinator who was reviewing satellite images of Tuesday's weather to explain the event and who is researching a similar outbreak of "milky rain" in southern Arizona in January.

The Texas Commission on Environmental Quality on Thursday put out its initial account of Tuesday's event as caused by a "complex mix" of pollutants, citing smoke from Mexico and Central America, localized plumes of dust in Texas and Mexico and wildfires in South Texas aggravated by the strong winds.

This came as part of an unusual juxtaposition in which the wind-blown dust came before the rain instead of after it, said Robert Blaha, a National Weather Service meteorologist based in New Braunfels (who was not the source of the initial ash description.)

Forrest Mims III, a science consultant and a freelance columnist for the Express-News, took a sample of the stuff from his window and put it under the microscope, forwarding some of his findings to TCEQ.

"There's one black spore and there are three possible soot particles and everything else is dirt, dust, sand. I would say that it's probably less than 1 percent smoke, and that's being generous," he said.

Joe Baskin, the weather service meteorologist who initially thought that what blew over here was mostly smoke since that's what it looked like in photos, said another look indicated that it likely was dust. (The weather service isn't responsible for investigating the stuff once it leaves clouds.)

David Gay, acting director of the Illinois-based National Atmospheric Deposition Program, said his government-funded network of researchers had five sample sites in South Texas and would be able to review initial findings as early as next week.

Sounds like a good day to be a researcher.