Mt. Rose and Copper Mountain have both announced that their Opening Days will have to be postponed. The warm fall did not discriminate between Nevada or Colorado resorts, stymieing their efforts to make enough snow to hit their previously announced opening dates. Copper Mountain pushed back its opening from Nov. 6 to Nov. 13. Mt. Rose, which was planning on opening Thursday, didn't immediately give a new date. Copper Mountain was initially able to start making snow at the beginning of October, but other Colorado resorts had more trouble through most of the month. And while Arapahoe Basin and Loveland are opening today, the Oct. 29 kick off to Colorado's ski season represents the latest start in 20 years.