As someone who works outside, I can tell you there is no 100% waterproof attire. Having said that, there is a big difference between standing in one spot for 3-4 hrs and actually working/moving around in it for 8+ hrs. Rain suits are your best bet, but trust me, somehow the water always finds a way in. If it's a cold rain, I always like to wear thermal under shirts and pants. These truly help alot. Also wool socks with some kind of waterproof boot. This will drastically help keep your feet warm.