Check out Helly Hansen Workwear, I use a light weight waterproof coat over my warm winter jacket. The coat is a #70190 with hood and is 100% waterproof, fits right over my dry wear and easy to take off when rain lets up. There are also some heated coats and boots that use your power tool batteries, but if its that cold I am going in by the fire!
Helly Hansen Cavendish? Jacket (70190)