Walla Walla Wall Cloud

May 06, 2013

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Photographer: Tim Nelson; Tim's Web site
Summary Authors: Tim Nelson; Jim Foster

The photo above shows a dramatic wall cloud blasting through Walla Walla, Washington on April 4, 2013. It was taken from the balcony of our fourth floor apartment about 20 minutes before sunset. The view is to the west, but the angle is so wide that it covers the south to northwest quadrant of the sky. This sort of storm cloud isn't all that unusual in the U.S. Midwest but is infrequently observed in the Palouse region of southeastern Washington. Wall clouds form on the inflow side (southwest side, in the Northern Hemisphere) of thunderstorms -- toward the rear of the storm, where the strongest updrafts occur. Funnel clouds quite often descend from the base of wall clouds. Though a severe weather warming was issued by the National Weather Service, little damage was reported with this particular storm. Photos taken at about 7 p.m. on April 4, 2013.

Photo details: Camera: Nikon D5100; Lens: 28-55 mm Zoom with image stabilization and Auto-Focus; Focal Length: 18.0 mm; Exposure Time: 1/25 Sec; F-Number: f/3.5; ISO Speed Rating: 100. 15 photos stitched together using Hugin.

Note on the title: We thought this was likely a shelf cloud but "Walla Walla Wall Cloud" had a too good to be true ring to it.