In general cold fronts move faster than warm fronts, and may thus catch up with a warm front ahead – the result is an occluded front
There are two types of occluded fronts: warm and cold, depending on whether the air behind the cold front is warmer or cooler than the air ahead of the warm front
Cold occlusions are the more common type in the UK
Occlusion is part of the cycle of frontal development and decay within mid-latitude low pressure