Due to an imminent winter storm, the Glacier Point Road will be closing Thursday, November 2, 2017. I also expect the Tioga Road and Tioga Pass as well as Highway 4 (Ebbets Pass) and Highway 108 (Sonora Pass) to also close for the storm.
For the most up to date road conditions within Yosemite National Park call 209-372-0200 then press 1 and then 1 again.
To check for chain controls on Highways 120 and 41 leading into the park, which may receive snow in some spots, please refer to the California Department of Transportation website here: http://www.dot.ca.gov/cgi-bin/roads.cgi