What characteristic defines a warm front?

A warm front is characterized by the gradual rise of warm air over cold air. As the warm air moves into an area occupied by colder air, it rises gently, leading to a gradual increase in altitude. This uplift causes the warm air to cool and condense, often resulting in cloud formation and precipitation.

The nature of this interaction is key to understanding weather patterns associated with warm fronts. Typically, ahead of a warm front, cloud cover will increase, resulting in prolonged, steady precipitation as the warm air ascends. Unlike cold fronts, which can lead to abrupt weather changes, warm fronts often produce more gradual shifts in temperature and weather conditions.

While a sudden drop in temperature is typically associated with cold fronts, heavy rainfall followed by snow can occur because of complex interactions but is not a defining feature of warm fronts. Similarly, vertical air mass movement is a broader concept that applies to various atmospheric phenomena, not specifically defining warm fronts. This understanding highlights the importance of the gradual rise of warm air in the context of weather forecasting and patterns.