How do fronts cause weather changes?

Answer 1

When fronts meet, the cool air undercuts the warm air and causes the warm air to rise and create tornadoes, associated with rain.

Answer 2

For instance, warm air is less dense than cold air. So, when two types of masses meet, warm air generally rises. Also, fronts are associated with weather in the middle latitudes.

Answer 3

A weather front is a boundary separating two masses of air of different densities, and is the principal cause of meteorological phenomena.