Horizontal snow on a ridge was successfully held at bay with my umbrella! The storm was completely unexpected - I brought it for sun, not precipitation - and I collapsed my trekking poles, swapped them for the umbrella, and trudged up the ridge holding it at a 90 degree angle so I could see where I was going. Why would I have anything snow gear on a low elevation coastal hike in May? At least I didn't have flying snow piling up on my face.