Step 1: Cloud formation begins on the ground. Rays of sunlight warm the Earth.

Step 2: The air in contact with Earth's surface heats up and begins to rise.

Step 3: A bubble of warm air (convection cell) continues rising until it cools to the same temperature as the atmosphere.

Step 4: Water vapor in the bubble begins to condense on particles in the air.

Step 5: As water droplets combine, they form clouds.

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