horrible noise when brakes are wet

There is wear indicator that screeches when the pads are worn too low. If you have more than 50K miles on the originals, it may be time to replace them. A least pull into some shop and have them inspected. A good mechanic can look through the wheels and see the pad thickness without disassembly. I used to check them in the parking lot but some mechanics want to bring it in on the rack to guarantee they get the work.....$$$.

Rust, brake dust, cheap pads, worn pads and rotors, all make for noisy brakes, especially when adding moisture to the equation. My want to get it in to a shop and have your brakes looked at.

You might be hearing the ABS kick in. Slick tires won't help.