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Mammatus Clouds over Nebraska

Explanation: When do cloud bottoms appear like bubbles? Normally, 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. The mammatus clouds pictured here were photographed over Hastings, Nebraska during 2004 June.

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Mammatus Clouds: they seem to appear in many places from time to time!

Stunning! Always fun to see some unusual clouds.One summer ,during a perfectly clear blue sky,you could see this dark iron shaped wedge of darkness in the West...it soon became a full blown tornado type storm..small trees at right angles.We stopped and took refuge in a used car lot office....I know this is a personal observation and doesn't have anything to do with the apod. ...I will never forget what it looked like virtually coming out of nowhere.It reminded me of a battleship coming across water.