As we investigate the question What is weather? We are learning about warm fronts and cold fronts.
When a warm air mass moves into a cold air mass, the result is a warm front.
When a cold air mass moves into a warm air mass, a cold front occurs.
In both warm and cold fronts, the warm air rises above the cold air mass, as illustrated in the image below.
The red water baloon represents a warm air mass. The blue water baloon represents a cold air mass. The cold air mass sinks, because it is much colder and more dense than the air around it. The warm air mass floats because the air inside it is warmer and less dense.
