BandJ,
The east entrance into Yellowstone is only open from 8am to 8pm. They are rebuilding the entire road from the entrance up to top.
The road is open during the day but they said to expect delays of up to half hour, so you may want to choose another entrance.
Also Beartooth parkway is closed because of mudslides but the Chief Joseph is open to the NE entrance.
This info was on the Redlodge, Mt. website yesterday.
Here is a link
http://www.redlodge.com
http://www.nps.gov/yell/planvisit/or...l/roadclos.htm