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March 2nd, 2010
Snow Conditions Report
Rocky Mountain National Park
Snow conditions are still highly variable above 9500' in RMNP and another dose of snow brought a few more inches of depth to the park high country on the last weekend of February.
On a recent tour through the Loch Vale, Otis, and Tyndall Gorges, we found a snowpack that ranged from an average of 1 meter to more than 5 meters in depth with strengths ranging the full spectrum as well from weak to strong.
The snowpack profiles that we looked at in numerous locations last weekend showed substantial strong over weak layering in the top meter, yet our column tests gave minimal results at these interfaces and we found overall good stability.
Areas where wind loading usually produces a very deep snowpack by this time of year are strangely some of the thinner areas at the moment, and these include the Terrain Park and Banana Bowls.
Apparently the wind has not been busy enough loading these treeline east and north aspects at the right times as the snowpack is closer to 1m average in areas where it would usually be in the 3m range by this time of year.
Based on observations from over a decade in RMNP, I believe that in average years, at least 50% of the snowpack total in the Terrain Park is the direct result of lee loading.
A week-long
spell of calm weather following our biggest snowfall of the season was
then followed by high winds, but his lull gave the snow enough time to
settle and sinter, and bonding seemed to keep enough of it from sailing
away once the wind's returned.
 More than 500 avalanches have been reported in the state of Colorado in the last week, with one skier fatality nearby Aspen and a skier near miss in the Indian Peaks.
The reality is that there are still many trouble spots in the backcountry of RMNP and we observed crowns and debris in the glacial headwall of Chaos Canyon and on the lee slopes adjacent to the Dead Elk Couloir over this recent weekend's tours.
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Well developed Depth Hoar facets taken from the base of a 70cm snowpack (pictured below at left) on an east-facing slope in the Tyndall Gorge near the Bear Lake trailhead.
A collapsing snowpack in these treeline locations made for deep postholing in snowshoes off-trail, bouncing off rocks on ski's, and an obvious indicator of a very weak snowpack construction in these shallow areas.
If you're looking to increase your risk management skills in the alpine environment, I invite you to join my final Avalanche Field Seminar this season, taking place from March 20-21st in Rocky Mountain National Park. There are still openings for this field-based, hands-on course for skiers and snowshoers with previous backcountry experience who would like to train with an experienced avalanche instructor.
Click on outlined photos to enlarge.
Skiing nearby avalanche paths, such as the base of the Dragontail Couloir (pictured), presents some potential risk on a March 1st Outing. It's best not to gather at these most exposed areas of an up-track.
In this bowl, we found a pencil hard, 6" thick bed surface that had been formed and buffed by winds in the last week of February. This slick surface made for tougher skinning conditions. The riding was fast on this firm base as the 4-10" of non-cohesive snow on the surface was not bonding to this bed-surface very well at angles above 35 degrees. Sloughs were occurring without new snow, heat, or human influences while we were present on this calm Monday in March.
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Luckily for our Avalanche Seminar participants on the Feb. 27-28th weekend, we were greated by the sight of a fresh slab nearby the aspen covered slope, 300' above Bear Lake to the west. (Photo at right)
We were able to spend a morning studying the snowpack in this treeline, lee location, and found a pencil hard slab in the upper snowpack above a four-finger layer of loose facets that proved reactive in compression tests.
 (Above) Chris and Dan doing a test pit in the middle of the Otis Redding Couloir (41 degrees) on the ridge east of Otis Peak during a ClimbingLife Guides Avalanche Seminar. We often ski in this couloir and similar terrain on our one day Steep Skiing Clinics, taking place on March 7th and April 10th.
In the above location, we found some avalanche potential in the top 50cm where 30cm of new snow was resting on a finger hard 20cm thick slab sitting on a thin layer of 4-finger facets that gave us a CT14 result at the strong over weak interface. We had no results with extensive ski cuts in this tight terrain feature.
 (Above) Tyler Duncan dropping a knee in the Dead Elk Couloir on March 1st, 2010.
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(Above) Wind-loading on a slick bed surface in the middle of a 45 degree convexity helped produced this small slab release (20 x20m) above Bear Lake in RMNP; likely a natural that occurred around Feb. 26th.
The current avalanche danger rating is CONSIDERABLE for these lee and cross-loaded aspects in RMNP (N,E,S) and backcountry travelers should test the snowpack regularly with ski cuts, test slopes, column tests and hand shears to check slab cohesion, and pay attention to snowpack sensitivity and propagation potential.
With much of the weakest snowpack in the treeline areas, the 'forest strainer' terrain trap often present in these locations can make even a small slide produce bad results.
(Above) The resulting avalanche debris from the release of a 10cm thick hard slab with a foot of fresh snow on top that released on steeper slopes above Bear Lake and that were likely naturally triggered during snowfall on the 26th of February.
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(Above) Tyler perfecting his tele-turn in fresh snow and sunshine on the Dragontail Apron.
February through May are the biggest snow months in the Front Ranges, so we have plenty of time yet for skiing season to come into shape and we're looking forward to daily forays on ski's in the months to come.
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(Above) Matt Kaufman sliding on silk on the Dragontail Apron, March 1st, 2010.
Deeper snow in this location (avg. >3m) and stronger layering due to hard wind slabs, along with constant slouging which lays down a thick base that better supports this steeper terrain.
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Winds over the last twenty-four hours have increased again with gusts along the Front Range at 12k into the 30's and so ridgetop locations are being scoured as I write. Lee loading on the eastern aspects and north and south cross-loaded aspects will increase and sensitive soft slabs could result on many slopes where loading has occurred.
Always check the current Avalanche Danger rating from the CAICand especially the accident reports as these help identify snowpack issues and terrain features that are contributing to the rash of accidents that have been increasing in recent weeks in Colorado and the U.S. Rockies.
Unfortunately, we still have many weeks and months before there will be much change occurring to strengthen what is a mostly weak and faceted snowpack and it may be melted before it has time to metamorphose into the well-bonded snowpack that we desire for spring climbing and skiing.
 
(Left) The Hourglass Couloir on the NE corner of Otis Peak is a good example of unsupported terrain that requires a very strong and filled-in snowpack to support these steeper slopes. (Right) Chris and Dan investigating the snowpack in the 40 degree terrain of the Otis Redding Couloir. We found more than 3 meters of snow depth at this location.
 
( Left) Mike Caputo soaring down the Dragontail Apron on March 1st, 2010. (Right) Tyler Duncan traverses through the debris path before dropping a knee in the Dead Elk Couloir.
Eli Helmuth is an UIAGM Licensed Mountain Guide and AMGA Certified Rock, Alpine, Ski Mountaineering Guide, and the father of Finley Cameron Helmuth, on a new bike at his recent Second Birthday party.
Contact us at:
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or call 970.744.4898 to plan a fun-filled and educational mountain outing with Eli Helmuth, RMNP's most experienced mountain guide.
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