A cold air mass moves in to replace a warm air mass, bringing colder air with more precipitation. This results in a __________. A warm air mass meets a cold air mass, and neither one moves the other. This brings clouds and rain or snow. This results in a __________. A warm air mass moves over a cold air mass, bringing gentle rain and warmer weather. This results in a __________.

1. Cold Front: When a cold air mass replaces a warm air mass, it typically brings colder air and often more precipitation.

2. Stationary Front: This occurs when a warm air mass meets a cold air mass, but neither is strong enough to move the other, leading to prolonged cloudiness and precipitation.

3. Warm Front: This happens when a warm air mass moves over a cold air mass, resulting in gentle rain and gradually warmer weather.

So, the answers are:
1. Cold Front
2. Stationary Front
3. Warm Front

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