River Runner

Sam Learner’s River Runner is an amazing visualization that traces the path of a raindrop falling anywhere in the contiguous United States to where it reaches the ocean or leaves U.S. territory. “It’ll find the closest river/stream flowline coordinate to a click/search and then animate along that flowline’s downstream path.” It’s a tad resource-intensive, and if you end up in the Mississippi basin it will take a while (and make clear just how big that river system is), but it’s absolutely transfixing.