Warm Front
![Side view (A) and weather map representation (B) of a warm front](/sites/default/files/media/images/warm-front_lg.gif)
Windows to the Universe, Lisa Gardiner
A warm front forms when a warm air mass pushes into a colder air mass as shown in the side view (A). A warm front is represented on a weather map with red semicircles pointing in the direction that the front is moving (B).