Here is the motherlode of weather data for Alta.
The yearly averages. Alta has had generally above average snowfall the past 17 years.
On average, the daily depth begins to build what I consider an acceptable early season depth of 40" about Dec 10th.
The melt begins about the 2nd week of April.
The real storms start about now, mid-November, and continue through the 2nd week of April when the snowfall plummets by about 30 inches per month. But they are still getting snow in May. It doesn't snow in July and August.