Yellowstone National Park officials, anxious to get the park's East Entrance Road open to traffic but conscious of avalanche potential along Sylvan Pass, plan to allow traffic along it on a limited basis beginning Wednesday.
Under the plan announced Tuesday, traffic will be allowed between 6 a.m. and 10 a.m. daily. Outside of those hours, no traffic will be allowed along most of the 27-mile road that links the East Entrance to Fishing Bridge and the junction with the Grand Loop Road.
The East Entrance Road opened for the summer season on May 6, but five days later an avalanche that covered more than 200 feet of the road beneath 20-30 feet of snow on 8,530-foot-high Sylvan Pass forced its closure. Since that slide last Wednesday there haven't been any more avalanches, but "the report we’re getting down from the rangers is there’s still a lot of snow that needs to come down," park spokesman Dan Hottle said Tuesday.
Crews were able to remove that snow from the road by Sunday, but the possibility of additional slides has prompted the limited window for travel along the roadway.
"Park avalanche forecasters have determined that the safest travel window across the pass will be during those early morning hours between 6:00 a.m. and 10:00 a.m.," a park release said. "Forecasting staff are closely monitoring weather, snowpack, moisture and all of the complex factors that go into determining the safety of opening the road for public travel.
"... Visitors headed westbound into the park should leave Cody no later than 8:30 a.m. Travelers headed east out of the park toward Pahaska Tepee and Cody need to be across Fishing Bridge by 9:15 a.m.," the release added.
There were no plans to station spotters along Sylvan Pass, which is below 20 avalanche chutes, Mr. Hottle said.
In addition to the concern over avalanches, the spring runoff has washed out a section of the road east of Sedge Bay along the northeast shore of Yellowstone Lake, making the eastbound lane impassable for about 60 feet, the release said.
"This section of the road will be limited to one lane travel only with the traffic flow regulated by flaggers or automated traffic lights. Visitors can expect some temporary delays on this section of road for several weeks until extensive repairs can be made," the park said.