According to http://www.nps.gov/yose/planyourvisit/tioga.htm, Tioga Pass Road is just sort-of plowed. They say: Plows have reached Tioga Pass and will now be working on widening the road. Plowing continues Monday – Saturday. Average Snow Depth is 4 to 6 feet. Plowing operation will continue today.
I just checked http://www.dot.ca.gov/cgi-bin/roads.cgi. It says:
108: IS CLOSED FROM 26.4 MI EAST OF STRAWBERRY TO 3 MI WEST OF THE JCT OF US 395 /SONORA PASS/ (TUOLUMNE,MONO CO) – FOR THE WINTER – MOTORISTS ARE ADVISED TO USE AN ALTERNATE ROUTE
4: IS CLOSED FROM EAST END OF LAKE ALPINE TO 7.2 MI WEST OF THE JCT OF SR 89
/EBBETTS PASS/ (ALPINE CO) – FOR THE WINTER – MOTORISTS ARE ADVISED TO USE AN ALTERNATE ROUTE
120: IS CLOSED FROM CRANE FLAT TO 5 MI WEST OF THE JCT OF US 395 /TIOGA PASS/ (TUOLUMNE, MONO CO) – FOR THE WINTER – MOTORISTS ARE ADVISED TO USE AN ALTERNATE ROUTE