Mammatus Clouds Over Tobyhanna, Pennsylvania

April 20, 2016


Photographer: Tom Wildoner
Summary Authors: Tom Wildoner; Jim Foster

April 2016 Viewer's ChoiceShown above is a huge formation of mammatus clouds observed over Tobyhanna, Pennsylvania, during the afternoon of March 17, 2016. Mammatus are sometimes seen when unsettled weather occurs. Thunderstorms are almost always in the vicinity, sometimes in the process of decaying, but the weather need not be severe for these clouds to be reported. For mammatus to form it's thought that downdrafts must play a role -- cooler air from aloft pushes through the cloud base resulting in the pouch-like appendages.

Photo Details: Camera Maker: Apple; Camera Model: iPhone 5s; Focal Length: 4.15mm (35mm equivalent: 29mm); Aperture: ƒ/2.2; Exposure Time: 0.0005 s (1/2160); ISO equiv: 32; Software: PaintShop Pro 15.00.