UPDATE WEDNESDAY 4:28AM: NDOT says chains or snow tires are required on I-580 through Washoe Valley. UPDATE 3:18PM: Geiger Grade, State Route 341 is now open with chains or snow tires required. Meanwhile, I-580 from Mt. Rose Highway to Bowers Mansion area, SR 338 and Mt. Rose Highway from Douglas Fir Drive to Fairview Boulevard remain closed.