Are all snowflakes created equal?

[schubwa]

I'm home packing for a hut trip to Canada (prolly bring my camera) and noticed some similarities and differences in seasonal snowfall figures versus total snowpack depths. For example:

Alta, UT= 374" season with a 105" base (I'm thinking 9600' level off Collins Lift)

Mt Bachelor, OR= 334" season with 90" base (6300') and 106" (7600' @ mid-mountain).

Let's use Bachelor's 106" number as it's up the hill like Alta's and at a fairer altitude for comparison purposes. So they got 40" less snowfall so far this year and have the same depth. Of course it doesn't take high intelligence to imagine Alta squeezing more snow out of each inch of water that falls each month. Alta's yearly average of 8.54% density has to beat Bachelor's figure, which isn't published. If an inch of water equals ten inches of snow (common rule of thumb), I figure Alta's yield has to be more. (Marc_c, you there?) I'm just guessing the 11% difference between the two ski areas snow density explains how one can get more inches to fall in each storm and still come up with the same settled snow depth. Preservation is sure to come into play, but Alta's extra 2000' elevation might cancel out Bachelor's higher latitude? Any thoughts?

 

[baldyskier]

I'm a little surprised that the ratio of current snowpack to season totals are as close as they are between Alta and Mt. Bachelor. Maybe the Bachelor powder was nearly as light as the Alta powder this year?

 

[schubwa]

Maybe the Bachelor powder was nearly as light as the Alta powder this year?

Ummm, hard to say without igniting a firestorm of bravado from Zion. No contest the quality is better there, I know 'cause started skiing LLC 44 years ago and got there a lot when I lived in LA, Mammoth and then Orange County. It's that most folks think we get heavy snow (all the time) a la Crystal Mountain, WA or Mt Hood. Just ain't the case.

PS: Season now at 343" with 6" new overnight (98',110"), crap I have to get on a plane this morning.

 

[Tony Crocker]

Snow at Mammoth, Alpine Meadows and Stevens Pass averages ~13% water. I would be surprised if Bachelor's is much different. High water content is better for building an early and deeper base. Like Baldyskier I would expect Bachelor's base depth to be much more with essentially the same snowfall as Alta (remember 40 inches of Alta's was in October).

There can be seasonal anomalies. Mammoth had one entire season in 2000-01 which was averaged under 10%. Despite getting 400 inches, the Memorial Day base depth was subpar.

Mt. Bachelor has the highest ratio of max base depth to season snowfall that I have the data: 40% over 35 seasons. No surprise with the combination of coastal snow and excellent preservation (Mammoth is 39%). I have less data for LCC. 23% over 9 seasons at Alta and 25% over 17 seasons at Snowbird.

I think Mammoth/Bachelor snow preservation overall might be a little better than LCC's but I ascribe the vast majority of the difference in base depth/snowfall ratios to the higher water content snow.