First snow is generally mid-october to early november. Last snow is in mid-march to late-April. Snowiest months are January and February.
This is too broad a question to answer, since Colorado is large and topography plays a big part in its climate..In the mountains, it can snow any day of the year..I have waken up to 2" of snow on my tent in early August. The first snow is generally in Mid to late September in the mountains and areas near Denver to the north.. most of the state receives snow until May 1, but the mountains continue getting snow into early June..
If you check the records at the Colorado climate center, snowiest months vary according to section of the state..most mountain areas are very snowy Dec-March..
near Denver March and April are snowiest..while in sw Colorado, Dec, Jan, Feb are snowiest..some of the heaviest snowstorms in Denver and the foothills nearby can get 3-6ft snowstorms in March and April. I have experienced two of them that large so far...
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actually in the denver metro area it usually snows October... not September.
This year (2010) we are still awaiting out first snow.. it's sure to snow on Halloween though... always seems to. Last year (2009) our first snow was enough to close schools inluding colleges for two days in the Denver area. A few years ago it was lightly snowing into June. It really depends on the year, if its an El Nino year or not. 2009 was supposed to be one, and yes we did get a ton of snow. 2010 is supposed to be MUCH dryer. If your looking for skiing and such, know that many of the resorts make their own snow, and being at a higher altitude many of them are infact still getting snow.
Some residents insist that its between July and June while others use Halloween and Easter as the benchmarks. Different locations and different altitudes provide different answers. October to March is the best answer.
Colorado has as much variation in seasonal snowfall as any state in the country, this being due to the Rockies that cut through most of the west of the state and the elevation differences elsewhere. Even east of the Front Range it varies considerable. Denver averages about 60", while an hour northwest in Boulder the average is over 80". A little to the northeast and down a little bit in elevation, Fort Collins averages about 55". South of Denver, Colorado Springs averages only about 40". Out toward KS the land slopes down, is pretty flat, and snowfall is a more uniform 20-25" annually.
The mountains themselves average a couple hundred inches, with 250-350" common in ski resort areas. West of the mountains depends on the elevation and topography nearby, especially to the west. Many places are very dry, and receive less snow even if they're colder. For example, some areas around Grand Junction average less than a foot annually. Durango in the southwest corner, for example, average 70" being a bit higher up.
The snowiest month's here in Denver is usually November and March.
If you're referring to lower elevations, and can start as early as October. When it does snow so early, it rarely sticks around however. Snow can fall in September in the mountains.
In town, about 180". It obviously goes up as you hit the slopes.
308 in.
March
Colorado
Up at the ski resort it is about 300''/year is the average. It's somewhere around half that in town.
The Province of Calgary is located in Canada. The average annual snowfall for the area is 49.9 inches.
120 inches is the average annual snowfall
25 inches of snowfall per year.
Checking the Durango Tourism sites I found 68" to be the average annual snowfall for the town of Durango, Colorado. However, the Durango Mountain Ski Resort, just 25 miles north of the town of Durango, claims 266" of snowfall annually.
Colorado
Average snowfall is about 30" annually.
The average snowfall for Oswego NY is 140.3" per year.
3 foot of snow
Up at the ski resort it is about 300''/year is the average. It's somewhere around half that in town.
Average snowfall is about 45 inches. See the related link for more.
The Province of Calgary is located in Canada. The average annual snowfall for the area is 49.9 inches.
The average Yearly snowfall in Newfoundland is 200cm to 300cm
120 inches is the average annual snowfall
Average snowfall in Nogales AZ is 3.1".
The deepest snowfall recorded in the US was at Tamarack, California with a depth of 451 inches. I do not believe there is any place in California that has never received snow. I have even been in Death Valley when it snowed. The average snowfall over Donner Summit is about 35 feet. So California has no "average snowfall." It depends on where in California one is when asking about the average snowfall.