Yellowstone Park is closed to fishing until Memorial Day. The Yellowstone River opens in the upper reaches July 15. Below Tower/Roosevelt, the Yellowstone River opens to angling Memorial Day weekend, but will be fishing good the end of June.
Reports for Yellowstone
Yellowstone Park is closed until Memorial Day weekend. High water is usually the case late May in the Lamar, Slough and Soda Butte drainages, but one never knows until you go! Expect to see stoneflies, caddis and blue-winged olive action on dries or nymph imitations should the water conditions be clear enough to fish.
Yellowstone Park is closed to fishing until Memorial Day weekend. Caddis, blue winged olives, golden stones and some PMD’s are generally flying around on these rivers on the West side of Yellowstone Park. Water conditions are usually high, but fishable on opening weekend, then falling into shape quickly in June.