Yellowstone National Park is closing all rivers and streams for fishing starting Wednesday from 2 p.m. to sunrise because of high water temperatures and low stream flows. Water temperatures have exceeded 68 degrees Fahrenheit (20 degrees Celsius) in recent days, and flows on many rivers are below long-term averages. Staff will continue to monitor the water temperatures. The park is advising anglers fish during the coolest times of the day and land fish quickly. Don't play hooked trout to exhaustion, and gently handle fish in the water and let them recover before release.