What term describes the boundary between two air masses?

The term that describes the boundary between two air masses is a "weather front." Weather fronts occur when two distinct air masses with different temperature, humidity, and density characteristics meet. This boundary is significant because it often leads to various weather phenomena, such as precipitation, changes in wind direction, and temperature shifts.

When a cold air mass encounters a warm air mass, for instance, the cold air can force the warm air to rise, creating clouds and possibly storms. Similarly, the interaction of air masses at a weather front is a critical factor in forecasting weather patterns.

While other terms like pressure zones and temperature gradients are related to atmospheric conditions, they do not specifically refer to the boundary between air masses. Air currents pertain to the movement of air rather than the interaction between different air masses. Understanding weather fronts is essential for meteorology and helps in predicting weather-related events effectively.