It is a waterless wash, so yes, it will clean after rain. Just make sure you have several towels and you should be fine. Just like PB Spray and Wipe, you should wipe the product off, not rub. Keep flipping to clean sides of the towel and you'll be good to go. An added bonus to the BOGO is that DP Waterless is a great clay lube as well ... 2 32oz bottles diluted a little will last a very long time.