What is a front in meteorology?

In meteorology, a front is defined as a boundary or separation between two air masses that have different temperature, humidity, and density characteristics. This difference often leads to various weather phenomena. When two air masses meet, they do not mix immediately; instead, the denser air mass tends to push underneath the less dense air mass, which can create significant weather changes such as precipitation, storms, and shifts in temperature.

The presence of a front often leads to the development of clouds and changes in weather patterns, which is why it is crucial in weather forecasting. Understanding this concept helps in recognizing that the interaction of different air masses is a fundamental aspect of meteorological processes. Therefore, the choice that identifies a front as a separation between air masses of different densities accurately captures its role in atmospheric science.