The resort was supposed to open on November 12, but the recent storm dumped several feet of new snow, allowing the resort to push up opening day.
This is the second earliest opening in resort history.
In 1994, it opened on October 8.
"We are so excited to start the season nearly four weeks ahead of schedule and to be able to reward our guests with a free day on the slopes," said Howard Pickett, chief marketing officer of Mammoth Mountain.
For more information on Mammoth Mountain, click on the link below or call 1-800-MAMMOTH.