Stratocumulus undulatus, Stratus opacus, Cumulus humilis + congestus, and Cumulonimbus
Includes educational information about the cloud formations on the back of each stamp
In celebration of National Stamp Collecting Month, the U.S. Postal Service issued this sheet of 37-cent, Cloudscapes commemorative stamps on October 4, 2004 in Milton, Massachusetts. In a joint effort with The Weather Channel, the American Meteorological Society (AMS), and the National Weather Service, USPS launched the "Reach For the Sky and Collect Stamps" promotion. This pane of 15 stamps is based on striking photographs of various cloud formations, and on the back of each stamp is a description of that formation.