Temperatures were low enough for snow making to begin Oct. 25 at Heavenly Mountain Resort.
Officials say the West Coast's largest snow-making system can cover
73 percent of Heavenly's trails.
"It's comforting to know that when it's cold, we have snow," said John Wagnon, Heavenly's vice president of marketing and sales.
Heavenly has targeted Nov. 19 as its opening day.
On Donner Summit, Boreal Mountain Resort plans to open for skiing and riding today, conditions permitting.