Chinook Pass and Cayuse Pass on the east side of Mount Rainier have been closed for the winter season. WADOT and the NPS consider the snowpack, the avalanche danger, and the weather forecast when making the decision to close the highways for the season, and it typically happens in mid-November.
Check out the park's road status webpage for more details.
It's also getting to be the time of year when the road to Paradise is closed at night for snow removal operations. The park's twitter feed is the best way to track when the Paradise Road will be open on a daily basis.