Rain leaks in on passenger side floor

Whenever it rains the passenger side floor will get wet. Water seems to coming in underneath the plastic trim along the the floor where the door closes. The door itself stays dry and all other areas remain dry as well. It is just the carpet. The problem seems to have gotten worse the last few months. It does not matter if I am driving or if the jeep is parked, the carpet will get soaked with a good hard rain. Any help is much appreciated!