If you have PVs in an area where it snows this won't likely be a surprise - solar panels shed snow, all at once. When they shed snow things underneath them tends to get pretty messed up. We had snow here in CT on Wednesday, and yesterday as I pulled my car out of my garage my panels decided that was the perfect time to shed... Right onto the roof of my Model S. For a moment I expected the pano to cave in on me, but it didn't. In fact, there isn't even a scratch on the car! The rhododendron next to the driveway, however, is totally destroyed.