The dark blue areas still had 20 inches or more of unmelted snow as of Thursday morning. The wisps of magenta represent areas with 40 inches or more. In western Maryland, some spots have the equivalent of 10 inches of rain piled up. The snowpack area drains to the Yough and Cheat rivers, which flow into the Mon and on to Pittsburgh.
You can keep track of river observations throughout the district at this website.