Answer:
Cold front usually brings the most severe types of thunderclouds and storms.
Step-by-step explanation:
Generally, there are four types of fronts that produce thunderclouds and storms:
1. Cold front
2. Warm front
3. Occluded front
4. Stationary front
However, it is only the cold front that usually produces the most severe types of thunderclouds and storms which are typically more violent and faster than the other fronts.
Violent thunderclouds and storms are usually produced whenever the coolest air around the ground raises up warm air into the atmosphere.