Plain English Meaning

Clouds are the visible bunches of water droplets or ice crystals you see in the sky. They form when moist air rises, cools, and the moisture turns from invisible vapor into tiny visible drops.

Full Definition

Visible masses of tiny water droplets, ice crystals, or both, suspended in the atmosphere. Clouds form when rising air cools to its dew point and water vapor condenses onto microscopic particles called condensation nuclei. The type, height, and shape of a cloud reveal what the atmosphere is doing — its stability, moisture content, and likely weather.

Context Anchor

Pilots encounter clouds in weather reports, , , and in when deciding whether they can see enough to safely.