All roads close to public motorized vehicles at 8 am on November 5, 2018, except the road between the North Entrance and the Northeast Entrance. Outside the park to the northeast, the Beartooth Highway is closed, but the Chief Joseph Highway remains open.
This is when the fall bicycling shoulder season begins. However, the weather forecasters are predicting wind and snow for this weekend, so conditions will not be ideal. See the National Park Service’s Spring & Fall Bicycling for more. The shoulder season lasts until about the third week of November, when plowing operations stop so that enough snow can accumulate on the roads to support oversnow travel.
Then the Grand Loop Road will open to snowcoaches and snowmobiles on December 15, ending the fall season officially.
Photo credit: NPS photo from the Yellowstone National Park Flickr album, Jacob W. Frank, June 13, 2018.