A ski season is a period when skiing, snowboarding and other alpine sports are viable in an alpine resort. The season corresponds to when ski lifts are running and lift passes are available. Depending on the latitude and altitude of the resort, the season will typically run from early to mid-winter until mid- to late spring. Ideally the season will be over before the thaw begins.
A typical ski season has three stages, and therefore three levels of lift ticket pricing:
Off-peak, at the very beginning and ending of the season, when the number of lifts open is limited and the snow cover in the lower sections of the mountain is typically patchy.
Shoulder, during which the mountain is entirely snow-covered but lift pass sales are not sufficiently lucrative to justify opening all lifts or areas of the mountain.
Peak, during which all lifts and most if not all runs are open. These periods are usually at the height of the season or during school or public holidays.
Typically in the United States, a ski season lasts from late November to early April, however larger resorts in Colorado and California are known to spin the lifts as late as the 4th of July.