What characterizes cool air moving over a warm surface?

Cool air moving over a warm surface typically leads to instability in the atmosphere. When the cooler air comes into contact with the warmer surface, it gets heated from below, causing it to rise. This heating can result in the formation of cumulus clouds and, when conditions are right, can lead to showers or even thunderstorms as the unstable air continues to rise and cool, allowing moisture to condense.

This process is fundamental in meteorology, illustrating how temperature differences can drive atmospheric dynamics. In this scenario, instability is enhanced because warm air is less dense and rises, creating upward motion in the cooler air. If there is sufficient moisture available, this can result in precipitation. Thus, the characteristic of instability and the potential for showers is a direct outcome of this interaction between cool air and a warm surface.