¨Dawn Skyshow Over The Boulder Flatirons on 12 Dec. 2010
Since moving to the eastern slope of the Rocky Mountains I have enjoyed frequent sightings of these spectacular altocumulus standing lenticularis or lenticular cloud formations. Where stable moist air flows over a mountain or a range of mountains, a series of large-scale standing waves are formed on the downwind side. If the temperature at the crest of the wave drops to the dew point moisture in the air may condense to form lenticular clouds also sometimes known as "lee clouds," "wave clouds," "Clouds of Heaven," or "Angelships." As the moist air moves back down into the trough of the wave, the cloud may evaporate back into vapor...