North America
Best time to ski in North America: natural snow month by month
When natural snow has been most reliable at the 10 resorts Cirque models in North America, month by month, from eleven winters of weather data.
Every resort Cirque models here
Each cell is one month: the share of days with 30 cm or more of modelled natural snow at mid-mountain over the last 11 winters, from brown (often thin) to deep blue (snow-sure). Blank means almost none.
The short answer
The surest time for natural snow in North America has been January to April. In those months most of the 10 resorts Cirque models here were snow-sure in at least 9 of the last 11 winters, meaning mid-mountain had 30 cm or more of modelled natural snow on at least 90% of days.
Month by month
October: none snow-sure in any winter. Most natural snow at Whistler Blackcomb (11% of days).
November: 0 of 10 snow-sure. Surest: Whistler Blackcomb (4 of 11), Banff Sunshine (0 of 11) and Big Sky (0 of 11).
December: 1 of 10 snow-sure. Surest: Whistler Blackcomb (11 of 11), Revelstoke (7 of 11) and Jackson Hole (7 of 11).
January: 8 of 10 snow-sure. Surest: Whistler Blackcomb (11 of 11), Banff Sunshine (11 of 11) and Revelstoke (11 of 11).
February: 10 of 10 snow-sure. Surest: Whistler Blackcomb (11 of 11), Banff Sunshine (11 of 11) and Revelstoke (11 of 11).
March: 10 of 10 snow-sure. Surest: Whistler Blackcomb (11 of 11), Banff Sunshine (11 of 11) and Revelstoke (11 of 11).
April: 8 of 10 snow-sure. Surest: Whistler Blackcomb (11 of 11), Banff Sunshine (11 of 11) and Jackson Hole (11 of 11).
May: 1 of 10 snow-sure. Surest: Big Sky (10 of 11), Mammoth Mountain (8 of 11) and Whistler Blackcomb (7 of 11).
June: 0 of 10 snow-sure. Surest: Mammoth Mountain (2 of 11), Whistler Blackcomb (1 of 11) and Big Sky (0 of 11).
Resort by resort
Alta, USA, 2,600–3,216 m: snow-sure January to April.
Aspen Snowmass, USA, 2,473–3,813 m: snow-sure January to April.
Banff Sunshine, Canada, 1,660–2,730 m: snow-sure January to April.
Big Sky, USA, 2,072–3,403 m: snow-sure January to May.
Jackson Hole, USA, 1,924–3,185 m: snow-sure January to April.
Mammoth Mountain, USA, 2,424–3,369 m: snow-sure February to April.
Revelstoke, Canada, 512–2,225 m: snow-sure January to March.
Stowe, USA, 390–1,339 m: snow-sure February to March.
Vail, USA, 2,475–3,527 m: snow-sure January to April.
Whistler Blackcomb, Canada, 675–2,284 m: snow-sure December to April.
Questions
When is the best time to ski in North America?
For natural snow, January to April. That is when the most resorts Cirque models in North America have been snow-sure over the last 11 winters.
When does natural snow become reliable in North America?
The first month in which any resort Cirque models here was snow-sure in at least 9 of 11 winters is December. Resorts open on their own dates and many use snowmaking earlier.
Which resort in North America has the most reliable snow?
Of those Cirque models, Whistler Blackcomb: mid-mountain was snow-sure in 5 months of the year.
Does this include snowmaking?
No. These are modelled natural snow figures only, from ERA5 weather. Groomed pistes with snowmaking often ski better than this.