These infrared satellite images are made from a United States weather satellite located 22,000 miles above the Earth's equator. This allows us to detect cloud changes and cloud movement over time. By making use of the infrared spectrum, the location of clouds can be determined at any time, day or night. The height of the cloud is determined by its temperature.
Warmer clouds are closer to the ground and colder clouds are higher up.
One drawback of this method is that low clouds are occasionally indistinguishable from cold ground temperatures under clear skies. Occasionally, during arctic air outbreaks, the infrared imagery will indicate clouds when none are present.