I do it all the time. One HUGE tip: make sure that the padded seat/armrests are covered. If it rains on them, that thing will stay soaking wet for days. It'll even start getting moldy and smelly.

Nothing worse than climbing up the tree and sitting down, only to have your entire ass soak rightthrough the whitie tighties. That makes for a long, miserable day.

Keep the seat dry.

When I'm leaving mine out - I wrap the seat cushion in a garbage bag and bury it under a brushpile/logs.