Strange Vertical Sunset Clouds in Pittsburgh
WPXI and WTAE both had photo galleries this morning of strange clouds sighted last night at sunset in Pittsburgh. The clouds looked like tornadoes.
I believe they were examples of what I call "vertical" clouds and we've collected quite a gallery of them over at the AccuWeather.com Photo Gallery. The clouds are benign. Here's a photo I took of one in 2009:
Vertical Cloud 2009, by Jesse Ferrell
In that case, it was simply a vertically-growing non-tornadic cloud. Things can get a little "cloudier" (if you will) when the vertical structures are associated with thunderstorms, as in the video I took below in 2011. Although impressive in the time-lapse video, the clouds themselves were just what are called "scud" clouds and are associated with the edges of thunderstorms, where moisture rises upwards...
Another type of "vertical" cloud is a trick of illusion. Near the edge of a shelf cloud (as depicted here at the beach in a photo I took in 2007), the cloud can appear to go straight up, as in the photo below, even though your eye is being fooled by the curve of the cloud and the Earth.
Shelf Cloud Vertical Illusion illustration. When you're in close proximity of the termination of a shelf cloud, it may appear to be vertical.
This is what happened in the photo below, taken by Photo Gallery user "wrh1593" in 2007:
Arcus Cloud Viewed from Side (AccuWeather Photo Gallery / wrh1593)
