Dusty sunset

In case you missed it, due to all the dust, yesterday’s sunset:

Moreover, if you go to the NWS Tucson site and the forecast for Catalinaland, you will see icons showing pretty much the same thing for today and tomorrow as is in these photos. It will be interesting to see how deep the dust gets.

Where did all that dust come from, that plume of dust that moved into Tucson and environs during the mid-afternoon?

The Mexican Sonoran Desert NE of the Gulf of Baja.

You can see rivulets of dust being raised in this visible satelllite imagery loop (this will take a LOT of band width!) if you look hard at the desert regions southwest of the AZ border.  Also check out the U of A’s loop here, but that one will soon be overwritten, so good luck, and there’s nothing I can do about it.

Below, a still from that loop for 6:30 PM AST, near the time of the photos, with the dust origin region annotated with a red circle, something I have only recently learned to to with Apple’s Preview photo viewing software.  Dang.  The plumes are oriented SW-NE.  So, a few tons of Mexican desert came across the border yesterday to make AZ that bit higher in elevation.

Also in this sat image is the horrible fire near Silver City, NM, northeast of the red circle, the one that grew so much yesterday in the wind and heat.  You can see that the smoke plume was already reaching as far as Texas by the time of this image, 6:30 PM AST!

BTW, smoke particles are, in general, much smaller than dust particles are (hundredths of microns vs. a few microns) and the color of the setting sun can be used to help tell what you are looking at as far as aerosol particles go.  Smoky sunsets tend toward orange and red; dusty ones toward yellow, as above.

The End.