Which phenomenon occurs when a warm air mass goes over a cold air mass?

When a warm air mass moves over a cold air mass, the phenomenon is characterized as a warm front. This occurs because the lighter, warmer air rises above the colder, denser air. As the warm air ascends, it cools and can lead to the formation of clouds and precipitation. Warm fronts typically bring gradual changes in weather conditions, including an increase in temperature and humidity. The transition between the warm air mass and the cooler air is usually marked by prolonged, steady rainfall, followed by clear skies once the warm air fully replaces the cold air.

The nature of warm fronts makes them distinct from other types of fronts, as cold fronts involve the opposite scenario where cold air pushes under warm air, leading to more abrupt weather changes. Consequently, this distinction helps in understanding weather patterns and predicting the associated weather phenomena.