Lacquer won't hold up quite like an exterior-grade finish (i.e. spar varnish, urethane, epoxy,etc.) However, I like to dink with my bows all the time, so the following is appealing to me:
I finish the bow with lacquer, including a few frost coats. (Sometimes I seal it with thin superglue. This adds a degree of moisture protection, but is a touch tricky to apply smoothly and the fumes can be horrendous on your eyes!) Then I apply some sort of wax finish (Birchwood-Casey's Gunstock Wax, beeswax, paraffin wax, mink oil, etc.) to add a water repellent barrier. I reapply as needed, especially before and after humid or wet conditions.
No finish is completely waterproof. Epoxies are the best, but they're expensive and sometimes nasty to apply. Storing your bow in a controlled environment and touching up the barrier coat is just as effective. Plus, I think it's a little more fun. It'll give you something to do around the campfire