How much snow....?

Might not be an easy answer to find but knowing what the designed live load of the roof would give a person an idea how many pounds per square foot the roof could take. 1 cubic foot of water weighs approx. 62 pounds. So, wet snow versus powder would also make a huge difference.

Way back when, I had a Newmar fifth that stayed north during the winter. We had some big snows that left near 4 foot of snow on the roof. Called Newmar and talked to one of their engineers who advised that that quantity would not be a problem except for the roof vents, particularly when melting started.
Went out and shoveled the roof and felt tired but better.
Now, being retired, i've found that it very rarely snows here in Florida.