5th Wheel outside winter storage

Here in Calgary (Alberta, Canada) we store our 2005 5th wheel in the open in a storage facility with no cover. We get lots of snow and temps ranging from -40 to above freezing when the chinooks roll in (thanks goodness for the chinooks :) ). Just keep a vent slightly open to avoid condensation which can lead to mold. We've never had any problems with leaking, mold, flooring issues, etc... I'd have to think that it can't be much different where you are.

So I would say don't bother with a cover and just do the regular inspections and maintenance and you should be good to go...