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Mammatus Clouds Over Saskatchewan

Normal cloud bottoms are flat. This is because moist warm air that rises and cools
will condense into water droplets at a specific temperature, which usually corresponds
to a very specific height. As water droplets grow, an opaque cloud forms. Under some
conditions, however, cloud pockets can develop that contain large droplets of water or
ice that fall into clear air as they evaporate. Such pockets may occur in turbulent air
near a thunderstorm. Resulting mammatus clouds can appear especially dramatic if sunlit
from the side. These mammatus clouds were photographed over Regina, Saskatchewan,
Canada during the past summer.