Squall Lines contain some of the most violent and turbulent weather known. Squall Lines are usually parallel to a front. Choose here to view graphic of squall lines. Warm Fronts 1. The edge of an advancing warm air mass is called a Warm Front.
Warm air rides up and over colder air since it is less dense.
Choose here to view graphic of warm fronts. Warm Fronts usually move about 15 to 20 mph.