File:Popcorn Clouds over the Southeast United States (MODIS).jpg

English: Widespread popcorn clouds dotted the landscape over the southeastern United States on October 26, 2023, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this true-color image.

These clouds, which get their name from their popcorn-like puffy appearance, covered parts of nine states, from southern Kentucky in the north to Florida in the south. Despite the thick layer over land, the sky over the Gulf of Mexico remained clear. In the northeast, a gap in the cloud cover reveals dynamic red tones of autumn leaves in the mountains surrounding the tall peaks of Clingmans Dome and Mount Mitchell near the boundary between Tennessee (west) and North Carolina (east) in the Great Smoky Mountains.

Popcorn clouds, more properly called cirrocumulus clouds, form when heat from the Sun warms fields, forests, and land surfaces. The heat then rises, warming the air over the land and as it rises, the air also carries water vapor which, at the proper height and temperature, condenses into clouds.

Bodies of water, on the other hand, do not change temperature as rapidly; the water remains cooler even during full Sun exposure. The water does not heat up enough to significantly warm the air above it, preventing air from rising to make clouds. This, and many additional climate processes, can be traced to the different average heat capacity of water and land.