qOcclusion:
the warm air is cut off from the surface by the meeting of two fronts.
qUsually, a
fast-moving cold front catches a slow-moving warm front.
qA cold-type occlusion: eastern half of the continent where a cold front associated with cP air meets a warm front with mP air ahead.
qA warm-type occlusion: western edges of continents where the cold front, associated with mP air, invades an area in which colder cP air is entrenched.