From Water Vapor to Rain

Explore how solar heating, rising air, cloud droplets, and precipitation connect.

Interactive Weather Science Demo

Atmospheric cross-section · illustrative animation

Water vapor Cloud droplets / clouds Rain

Stage 1 / 4

Evaporation and Moisture Transport

Key Ideas

Cooling as Air Rises As air rises into lower pressure, it expands and usually cools.

Cloud Formation Water vapor condenses on tiny particles, forming cloud droplets or ice crystals.

Droplet Growth Cloud droplets grow by colliding and merging; ice processes can also contribute in cold clouds.

Precipitation When particles become large enough, they may fall to the ground as rain.

Note: This animation illustrates basic concepts. Real clouds and precipitation are also influenced by humidity, atmospheric stability, wind shear, terrain, and cloud microphysics.