Clouds and Precipitation

The air continues to cool as it it rises. As the air cools, it can hold less water vapor. Eventually, the air cools enough so that water molecules start to condense and form tiny droplets. These droplets are visible as clouds.

Play the video to see how clouds form.

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Eventually, the droplets become large enough that gravity causes them to fall to Earth as rain, sleet or snow.

An illustration showing the same cross section of a mountain range. There are clouds over the left side of the mountains and precipitation is falling from the clouds. Snow falls on the mountain peaks and rain falls on the forested mountain slope.

Click to view larger image

Take Notes

Predict what the moisture content of the air will be by the time the air arrives on the other side of the mountain range. Support your answer with evidence.