The eastern gate opened for the summer season at 8 a.m. Friday, with drivers prohibited from stopping in Sylvan Pass because of the snow conditions.
National Park Service officials had warned Thursday that the deep snow in the pass had the potential to release large, heavy and wet slides that could reach the road and limit travel.
"Yellowstone avalanche forecasters are closely monitoring the weather, snowpack, moisture, and all of the complex factors that go into determining the safety of travel across Sylvan Pass," the Park Service said in Thursday's news release. "Changing weather conditions or warmer temperatures may result in temporary or extended closures of the East Entrance road. Closures may be implemented at any time with little or no advance notice."
The park service said the potential for travel disruptions could last for several weeks until more snow melts and the snowpack stabilzes.
Friday's closure was announced via Yellowstone's official Twitter account shortly after 3 p.m., with the announcement of its re-opening coming a little before 6:30 p.m.
Similar snow conditions caused the park service to close the East Entrance for a week and a half in 2008 and limit travel to cooler time periods for another two weeks after that. The gate opened to unrestricted travel on June 6, 2008.