Photographer: Manon Boily 
Summary Authors: Manon Boily; Jim Foster

The photo above shows a striking mammatus sky over the imposing Chateau Frontenac in Quebec City, Canada. Following a deadly and nearly unprecedented heat wave (temperatures were in the mid-90s F, or mid-30s C, for nearly a week), strong thunderstorms pushed through the Quebec area, leaving behind theses breathtaking pouchy clouds. Mammatus clouds seem to form when downdrafts within a thunderstorm cell push cooler air through the base of the storm. They're sometimes observed on the underside of anvil clouds. Photo taken on July 2, 2018.

Photo Details: Canon 6D camera; 70 mm lens; ISO 400; f 8; 2.5-second exposure; processing to slightly darken the sky. Software: Adobe Photoshop CC 2018 (Windows).  

• Quebec City, Quebec Coordinates: 46.8139, -71.2080
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