Occluded Fronts
Sometimes a cold front will “catch up” to a warm front and overtake both it and the cooler air out ahead of it. If this happens, an occluded front is born. Occluded fronts get their name from the fact that when the cold air pushes underneath the warm air, it lifts the warm air up from the ground, which makes it hidden, or “occluded.” The symbol for an occluded front is a purple line with alternating triangles and semi-circles (also purple) pointing in the direction the front is moving.