Which type of clouds generally has a base lower than 2 km?

Low clouds are characterized by their bases typically situated below 2 kilometers (approximately 6,500 feet) in altitude. These clouds are often associated with weather patterns that involve more moisture in the lower atmosphere, leading to phenomena such as overcast skies, drizzles, and sometimes fog. Examples of low clouds include stratus, stratocumulus, and nimbostratus, all of which can create a thick layer that doesn’t rise very high into the atmosphere.

In contrast, high clouds are generally found at altitudes above 6 kilometers (20,000 feet) and are usually composed of ice crystals, while middle clouds typically lie between 2 and 6 kilometers (6,500 to 20,000 feet) and include altostratus and altocumulus. Ice clouds refer to clouds that consist primarily of ice crystals, but this term is more commonly associated with higher altitude clouds, particularly when discussing cirrus clouds, which are found at high altitudes. The distinct characteristics of low clouds make them unique in their general formation and behavior within the weather system.