Unfortunately, if it sees much more water, it will rust out very quickly. I would try and get a good quality car cover if you can't keep it inside. They won't completely block rain, but it will help. Wouldn't be surprised if your windshield is doing same thing and your insulation under carpet is wet.
When car does get wet, I would shop vacuum out the creases and crevices as best you can, and frequently check trunk pan and floorboards for moisture. Also keep your eyes on the frame where the torsion bars mount. Common rust area. Hope you don't mind these suggestions. This car is too cool to let it rust away.