Weather satellites do not have sensors that cover the visual spectrum to produce true colour images. Visible satellite images provide information about the observed cloud cover. Areas of white indicate clouds while shades of gray indicate clear skies, this is because thicker clouds have a higher reflectivity and appear brighter on a visible image than thinner clouds IR imaging is needed, as weather watching is essential day and night. Colour enhanced infrared satellite images are measurements of temperature thus only the differences in temperatures are visible. In an IR image darker is warmer and lighter is colder.
Low clouds tend to be warmer than higher clouds.
Water vapor images are useful for pointing out regions of moist and dry air. This provides information about the swirling troposphere's wind patterns and jet streams. Darker colours indicate drier air while moisture in the air is seen as white. The European Geostationary satellite currently transmitting to us is Meteosat 7. This satellite orbits the Earth at approximately 36,000 kilometres above the Earths surface and appears to be stationary over a specific point.