The best time to visit Mammoth is the summer. That is, if you’re not planning to ski. During the summer, the weather is warm and dry, in the mid 70s, ideal for outdoor activities like hiking and mountain biking.
Prices for accommodations are low during the summer, it will cost you less than $100 per night to stay in a 1 bedroom vacation rental.
For skiers and snowboarders, the ski season typically starts mid-November with just a few inches of snow at the beginning of the season. The best time to go to Mammoth to ski is before mid-December and after mid-January, when prices are more reasonable. The holiday season, all the way until MLK day in January, can be very expensive with prices for accommodations surging to $400/night for a one bedroom rental or hotel room.