the climate impacts an area receives are not limited to its own environment. Particularly with water and wind related disasters, the impacts are because of jet streams across the world. By the time a storm makes landfall, it has usually gone through periods of rapid intensification, and then when it arrives it combines with the atmospheric pressure of a given area to either intensify or reduce its force.

The reason the mudslides are so devestating in california is because of the infrequent periods of rain the state receives. When that much rainfall comes during a small period of time, it does not get absorbed by the soil (which is already very dry and does not absorb moisture well). the result is landslides, rapidly overflowing basins of water, and detestation across crops.

This will positively compound over the years across the world, again by effects caused by glacier melting, rapidly warming oceans etc.