This document discusses different types of weather fronts and storms. A cold front brings cool air that forms storm clouds and thunderstorms, followed by cool weather. A warm front brings warm, humid air that forms flat clouds and rain, followed by warm weather. Thunderstorms are caused by cumulonimbus clouds forming from a cold front, while tornadoes occur in severe low pressure zones and hurricanes form over warm ocean waters that create powerful low pressure systems, like Hurricane Katrina.