Tuesday, March 22, 2016

Graupel Skiing

Today was a day of discovery. Lachlan and I skied at Pilot Peak on a snow surface of 15 cms of graupel.
Nice turns today at Pilot Peak - Mores Creek Summit. Skiing surface; 15 cm of graupel.
Posted by Santiago Rodriguez on Tuesday, March 22, 2016

Lachlan enjoying himself on our second run at Top of The World, Pilot Peak.

Most of the day we were covered by flying snow, intense precipitation of graupel, and moderate to strong winds. Temps were not that cold, around -4 degrees C, but the wind put a bite into it.

The graupel was resting on a layer of wet polycrystals, that never got to freeze. We were saved from getting our skins wet by the thick and dense layer of graupel.
Lachlan at Top of the World, rare moment of visibility.
Below 7000 feet, at small slopes we were able to initiate small wet slabs as skied out via Summit Creek. Above 7000 feet we found generally stable conditions at Pilot Peak. Due to the nature of the graupel layer we did not detected surface instability due to wind slabs nor storm slabs. Quite simply, the graupel surface layer refused to form a slab!

Hand compression tests produced negative results.
Occasionally clouds parted, and the views were terrific. But it was only for brief moments that we could see anything at all.
Views from the Knob.
About to ski into Top of The World.
It is going to be intriguing to return in a couple of days and see how the additional snow predicted for the next few days will bond to the  graupel layer. And if the cold front and clear skies might have an impact in freezing the wet polycrystals buried 15 cms under the graupel. Stay tuned.

Below another short clip of today's skiing;

Lachlan Taggart working his splitboard at Pilot's Knob ridge - March 22, 2016
Posted by Santiago Rodriguez on Tuesday, March 22, 2016

Sunday, March 20, 2016

Back to Mores Creek Summit!

After 15 months of absence from Idaho, it is real good to be back to Idaho City and to ski tour the Mores Creek Summit backcountry ski area!

The special at Trudy's, no better way to work on the Blue Book entries.
Before heading up to MCS pass to ski tour, I had visit Trudy. And I mean not only stopping at Trudy's Place and having the perfect breakfast, but visiting with Trudy. Trudy is a dear friend, and its has been many years I have been visiting her restaurant business. Besides, her desserts are the best to be found anywhere in our galaxy. It was an emotional reunion after such a long time. We talked for more than an hour, and she got me up to speed about the changes around Idaho City. I was surprised to hear about the molybdenum mining being plan to take place at Coulter Summit, west of Wilson Peak.

The last two arctic winters I  have explored the French, Spanish, and Andorran Pyrenees, the Northeastern Swiss Alps, as well as the San Juan Mountains in Colorado while doing snow research and teaching avalanche courses. And during the austral winters, I have continued to explore the Argentinean Patagonian Andes as well as the Chilean Araucania. I can say without doubt, that I have not found any place in the northern or southern hemisphere that can begin to compare to the wonderful tree glade skiing of Mores Creek Summit.

Treed Chutes
Magical Glades.

Friday March 18th was a bluebird day, with light winds, temps below freezing, and strong solar radiation. Air temps went from -4 to 0 degree Celsius throughout the day. Indeed a warm day.

Snow surfaces were covered by absolutely beautiful surface hoar two dimensional plates, and near surface 3-D hexagonal crystals. It was not hard to find graupel at the snow surface mixed with SH and NSF snow crystals.

Surface Hoar

NSF and Graupel
The snowpack was deep and the coverage was superb. At 7500' the depth exceeded the 3 meters. The generous snowpack has opened many ski lines unavailable for several years.
3+ meter deep snowpack.
The views from the Freeman ridge have not changed - They are spectacular! It is always breathtaking to see the vastness of Central Idaho Mountains, with the Boise Mountains and the Southern Sawtooths covering the skyline from the north to the southeast.

Idaho Central Mountains caption
Southern Sawtooths in the distant horizon.
The skiing did not disappoint, with a 20 cm of soft 'Diurnal Recrystallized' snow at North and Northeast aspects. But any deviations past the 60 degree magnetic compass bearings had a very instruktional (k is q deliberate spelling for some my old friends) breakable crust.
North aspects skied great!
Tracks at Southeast aspect left a day earlier by another skier - breakable crust ... ughhh!
Conditions were generally stable, with two layers of concerns identified; a graupel layer at 30 cms, and a wet polycrystals interface at 65-70 cm depth. Test results produced moderate results (CTMQ2(RP)) at the graupel layer with no propagation propensity (ECTN). No evidence of instability was identified, with only dry loose skier triggered sloughs at steep shots.

Second easily identifiable layer from the surface down, is the 4F hard wet polycrystal layer under a Pencil hard 10 cm crust.
Graupel at the 30 cm interface
Very likely Saturday warm temps and strong solar radiation have impacted snow, but nights have been cool. It should not be hard to find northerly aspects at MCS (Pilot and Sunset) where skiing will be fun!

I noticed a skin track smacked in the middle of Freeman middle meadow. Not a big deal. I understand whoever get to put the uphill track can do it anywhere he wants. It is likely that the skin track was justified based on a pre-existing crust. However, the crust was gone from the meadow by Friday due to near surface faceting processes. Next time - Can we try to build the uphill tracks were we do not impact skiing terrain? THANKS!
Freeman middle glade with uphill track right in the middle of it.
Ahhhh .... It is good to be skiing in Idaho again!