Here's why:

* Temperature: Low clouds form below 6,500 feet (2,000 meters) where temperatures are generally above freezing.

* Water Vapor: The air in this lower atmosphere contains a significant amount of water vapor.

* Condensation: As the air cools, the water vapor condenses into tiny water droplets, forming the clouds we see.

While some low-altitude clouds can contain ice crystals, especially in the colder months, they primarily consist of water droplets.