Frequent contributor Glenn Brasch, the creator of Airport Courtesy Cars, sent us this photo he captured of a dust devil over Ryan Field Airport (KRYN) near Tucson, Arizona. He notes: “Strangest one I have ever seen, went straight up, then a huge arch.”
Thanks for being motivated to take a click of fun stuff in the atmosphere. It is great when we have particulates in the airmass to visualize what is really happening. As a gliderpilot, I would guess that the thermal kicked off and then encountered wind shearing as it cleared the gradient shadowing of buildings or vegetation and moved into the free-stream airflow. Flying gliders, we have to visualize how the thermals move, bend, drift, as they climb into the upper layers of atmosphere.
(Shear and gradient are different things.)
I tell students thermals are not like columns in front of the court building. They are actually a messy stack of Oreo cookies sometimes riding downwind on a skateboard. Think of the blade of grass in the wind, how it bends and undulates. It is not always standing up straight vertically….. Again, thanks for a photo that I can use with my students !