Have you allowed to build up on your rig before climbing up and clearing it off? Got real worried with 18+ inches of Sierra cement and finally did it. Wasn't easy but what a relief!
One of my buddies parked his motorhome under a metal carport cover. Unfortunately, the cover wasn't rated for much of a snow load, it collapsed and crushed the roof of his motorhome. A case where it would have been better to be uncovered than covered.