Ice climbing enjoys two seasons in the Eastern Sierra. The summer or "alpine" ice season typcially runs from late August until the first winter snows arrive later in the fall. Waterfall iceclimbing can be found in a handful of locations near Lee Vining, the most widely know of which are at Horsetail Falls, above June Lake, and in Lee Vining Canyon itself, above Lee Vining. SP Parker has written a guidebook on the ice of the Eastern Sierra. You can find it at our store, of course. Sierra Mountain Guides maintains a good winter ice climbing condition report. You can find it here .