Rain in my floor board

Each time it rains I get a wet driver’s side floor board. My truck is a '00 Chevrolet Silverado 1500. I have had the windshield checked and it is great. The door seals are in good shape and i doubt it is the heater core. HELP

Are you sure the floor isn’t getting wet when you use the A/C? It is a common problem for the condenser drain to leak onto the floor. There may be a small vertical tube under the dash on either side that has come disconnected, take a peek.