As long as they aren't kept in direct sunlight, I don't think it should be a problem in your zone.

I've used the baggie method more often for tenting and the only times I've roasted ones due to heat was when I forgot about them somewhere where direct sunlight got on them for too long.

when I try things like this, the leaves always seem to get moldy and then die

I have had luck with this method: cut off the bottom of the soda bottle, throw away the bottle cap and place the soda bottle over the plant. In hot weather, this method provides enough air circulation to keep bacteria away, yet it retains enough moisture to promote rooting.