Which type of atmospheric condition is primarily indicated by a cold front?

A cold front is a boundary between a cold air mass and a warmer air mass. When a cold front moves into an area, it typically forces the warmer, lighter air upwards, which can lead to the rapid development of clouds and precipitation. This process often results in stormy weather, including thunderstorms and heavy rain, especially where the warm air is forced to rise sharply. The sudden change in air mass brings about significant atmospheric instability, leading to these dramatic weather changes.

While other atmospheric conditions like warm, humid air or cool, dry air are characteristics of different weather systems, they do not directly pertain to cold fronts in the same way that stormy weather does. Foggy conditions might sometimes develop in association with certain front movements, but they are not the primary indication of a cold front. The dramatic shifts in temperature and pressure as a cold front passes are what primarily lead to the stormy weather characteristic of this phenomenon.