http://www.nps.gov/yell/planyourvisit/hours.htm
List 2012 Spring dates. Of course this all depends on the snow the park gets this winter
2012 Spring Road Opening:
Some park areas, entrances and roads are not open year-round! Most park roads are not open to motorized vehicle traffic between mid-March and mid-April while the roads are being plowed. The closed roads will begin re-opening starting April 20. See the spring schedule below for details. The North Entrance to Northeast Entrance at Silver Gate and Cooke City, Montana is open all year. Please note that this road is closed to east/west travel just east of Cooke City from late fall to late spring.
Roads will open, weather permitting, to motorized, wheeled vehicles as follows:
April 20, 2012-Weather permitting, west-side roads open to motor vehicles. Visitors will be able to travel by car through the park's North & West Entrances to Norris, Madison, Canyon, & Old Faithful beginning at 8:00 a.m.
May 4, 2012-Weather permitting, the road linking Canyon, Fishing Bridge, & the East Entrance opens to wheeled vehicles.
May 11, 2012-Travel from the South Entrance to Grant, West Thumb, Fishing Bridge, & Lake over Craig Pass to Old Faithful open to wheeled vehicles. Also, Tower Junction to Tower Fall opens to wheeled vehicles. The road from Cooke City over Colter Pass to the Chief Joseph Scenic Highway intersection to the Long Lake gate shall open as soon thereafter as possible. For information on roads outside of the park from Cooke City via the Chief Joseph Scenic Highway, travelers in Wyoming may dial 511; those outside of Wyoming may call 1-888-996-7623, or visit the Wyoming Department of Transportation website at
http://www.wyoroad.info/ .
May 25- (weather permitting) Dunraven Pass (Tower to Canyon).
May 25-(weather permitting)-Long Lake Gate over the Beartooth Highway to Red Lodge, Montana. For information on the Beartooth Highway to Red Lodge, Montana, travelers in Montana may dial 511; those outside Montana may call 1-800-226-7623, or visit the Montana Department of Transportation website at
http://mdt511.com/ .
In the spring, before park roads open to motorized vehicles, some roads are open to non-motorized recreational vehicles such as bicycles, roller skis, and roller blades. There will be some administrative vehicles traveling the roads at this time so be careful. See the Spring Biking Page for a map and more information.