USMC Improved Bivy in heavy rain test
USMC Improved Bivy in heavy rain. Inside is a Snugpak Jungle Bag.
I left it out overnight.
The next morning there was the slightest bit of condensation inside, just enough to feel on my hand. Not bad but ultimately it seems a bivy bag, any bivy bag, is for cool/cold conditions that have 50% or less humidity.