Spent the final day of the ACC Calgary AST2 going up Twin Cairns and skiing conservative terrain in the Sunshine slack country. Relevant observations:
Snowpack – variable 100 to 140cm deep and major wind damage. Whumpfing and cracking on the low angle terrain approaching the backside. Hollow like a drum in many areas up high. Ski penetration was 0 to 20cm. Foot penetration was variable but up to 60cm. The back side of Twin Cairns was wind-hammered sastrugi. The cornice along the ridge crest had built a bit since last week. Did a compression test on a nearly flat feature a few hundered meters outside the ski area boundary and got a moderate sudden planar (pop) result on the 11th tap down 20cm on 2mm stellar crystals (1 finger soft slab). Then got a sudden collapse (drop) on the 17th tap down 70cm on 1 to 2mm facets. Identical results on a second test.
Avalanches - Several size 1 to 3 natural avalanches in steep alpine terrain seen from the summit. Some failed near ridge crest; some just below rocky features. All on E and SE aspects. Notable is what appeared to be a size 3 in the Healey Creek slide path. Also notable is a size 2 and a size 1 that likely occurred during the storm on E facing lines that are sometimes skied off Twin Cairns. Crowns on the latter two now becoming obscured due to additional wind transport.
Weather – cool temperatures with variable sun and cloud with light to moderate winds all day. Not a lot of wind transport today as most of the snow had already been moved in the previous wind event.
Terrain Use – skied mellow terrain up to 25 degrees both up and down. Avoided overhead hazard. Ski quality poor to very poor on windward side and fair to good where sheltered or slight lee.
Cyril Shokoples MG
ACC AST2 Crew
Monday, February 8, 2016
Sunday, February 7, 2016
[MCR] Rockies, Lake O"Hara Feb 7th.
The wind blew like a bad movie here yesterday and it made a mess of most things TL and above. There seemed to be more scouring than wind loading and in the sunshine today we so only a few signs of avalanche activity. All the passes would be loaded on at least one side and we haven't made it up to Opabin pass once in the past 10 days because of windslab concerns. We certainly are not skiing big features like Schaffer bowl and generally still avoiding being under them. The snowpack is fairly facetted out in shallow areas so I am guessing travel on Cathedral and Collier would be poor unless it was wind packed.
The ice routes on Wiwaxy all look great. However the approaches must be assumed to be windslabs over facets so they would require a very careful approach.
Thinking forward to spring steep skiing, Mt. Lefroy and Glacier look much snowier than they have previous winters so they may just be in good shape if and when we get a trusty spring snowpack.
Larry Stanier
ACMG Mountain Guide
laristan@telus.net
_______________________________________________
These observations and opinions are those of the person who submitted them. The ACMG and its members take no responsibility for errors, omissions, or lapses in continuity. Conditions differ greatly over time and space due to the variable nature of mountain weather and terrain. Application of this information provides no guarantee of increased safety. Do not use the Mountain Conditions Report as the sole factor in planning trips or making decisions in the field.
See http://acmg.ca/mcr for more information.
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The ice routes on Wiwaxy all look great. However the approaches must be assumed to be windslabs over facets so they would require a very careful approach.
Thinking forward to spring steep skiing, Mt. Lefroy and Glacier look much snowier than they have previous winters so they may just be in good shape if and when we get a trusty spring snowpack.
Larry Stanier
ACMG Mountain Guide
laristan@telus.net
_______________________________________________
These observations and opinions are those of the person who submitted them. The ACMG and its members take no responsibility for errors, omissions, or lapses in continuity. Conditions differ greatly over time and space due to the variable nature of mountain weather and terrain. Application of this information provides no guarantee of increased safety. Do not use the Mountain Conditions Report as the sole factor in planning trips or making decisions in the field.
See http://acmg.ca/mcr for more information.
See http://informalex.org/subscribe.shtml#unsubscribe to remove your name from this list.
Saturday, February 6, 2016
[MCR] Whistler and Duffey Area Conditions
The Candadian Mountain and Ski Guide touring course spent the past week skiing in the Coast Range.
Whistler/Blackcomb Feb 1-3, 2016
Evidence of the Jan 28 rain event and associated natural avalanche cycle was widespread, with a supportive rain crust below 1800m and rugged refrozen debris on runs such as Husume, the Poop Chutes and Phalanx.
On Feb 2 visibility was good, and numerous aggressive lines in the Blackcomb backcountry were skied with sluffing to size one. A large cornice fall in the Trorey Col did not initiate an avalanche on the underlying slope.
A storm cycle began on Feb 3 with moderate to strong southerly winds, moderate rates of precipitation and increasing temperatures, with touchy windslabs developing near ridge tops. Cornices are growing rapidly.
Since our last field day in the Whistler on Feb 3, significant snowfall and continued winds have likely changed conditions considerably.
Duffey Lakes Rd - Marriot Basin and Cerise Creek Feb 4-5, 2016
Ski quality was very poor below treeline with 10-15cm of recent snow over the supportive Jan 28 rain crust.
A significant storm began on Feb 4 with snowfall, moderate to strong southerly winds and mild temperatures. By early in the day on Feb 5 the wind affect was widespread, one huge tree had fallen over the approach trail to the Keith hut, and windslabs were cracking with ski traffic at 1900m and above.
The early January SH layers were found down 1m and results on this layer in snowpack tests varied from resistant planar to sudden planar depending on location.
Jasmin Caton
Conny Amelunxen
Kirsten Knechtel
Marc Piché
_______________________________________________
These observations and opinions are those of the person who submitted them. The ACMG and its members take no responsibility for errors, omissions, or lapses in continuity. Conditions differ greatly over time and space due to the variable nature of mountain weather and terrain. Application of this information provides no guarantee of increased safety. Do not use the Mountain Conditions Report as the sole factor in planning trips or making decisions in the field.
See http://acmg.ca/mcr for more information.
See http://informalex.org/subscribe.shtml#unsubscribe to remove your name from this list.
[MCR] Rockies: Helen Shoulder
Up to Helen Shoulder today. Moderate winds most of the day with occasional strong gusts redistributing the recent storm snow. Precipitation was on and off with occasional snowfall amounts up to 2cm/hour. Likely less than 5cm new during the day with up to 10cm in the last 24 hours. Some soft slabs developing at treeline and in the alpine. A lot of cross loading on Dolomite peak. Limited visibility most of the day.
Of note: We did a Rutschblock on a short 37 degree safe slope on a slight convexity at the ridge crest on a lee wind loaded feature. Got an RB 2 whole block down 30cm in the recently deposited soft slab. Wow... Continued loading and got an RB4 whole block down 100cm on facets. Yikes !!!!!
Skied conservative terrain the entire day both up and down. Ski quality was good.
Cyril Shokoples MG
RescueDynamics.com
ACC Calgary AST2 crew
Of note: We did a Rutschblock on a short 37 degree safe slope on a slight convexity at the ridge crest on a lee wind loaded feature. Got an RB 2 whole block down 30cm in the recently deposited soft slab. Wow... Continued loading and got an RB4 whole block down 100cm on facets. Yikes !!!!!
Skied conservative terrain the entire day both up and down. Ski quality was good.
Cyril Shokoples MG
RescueDynamics.com
ACC Calgary AST2 crew
Friday, February 5, 2016
[MCR] Rockies: Bow Hut day trip
Well, the change that was in the wind has certainly arrived in the immediate environs of the Bow Hut.
Our ACC Calgary AST2 course went for a day trip to the Bow Hut today. By mid morning the west winds had already begun to pick up to moderate and light snow was falling at a rate of less than a centimeter an hour. At noon we ran into Nick’s group from Yamnuska descending from the hut and he mentioned that he felt soft slabs were already beginning to form.
We could see the snow starting to be redistributed in the rocks above and we decided to run up and down to the hut and see how good a track we could set and how safe we could be. We also felt the soft slab formation and a few isolated small features in the immediate lee of the wind were definitely beginning to behave like slabs. The final slope below the hut had some thin 10 to 15cm soft slabs that sheared very easily in isolated locations. We had already had the discussion that at the first sign of this becoming any thicker or more widespread we would just turn tail and run. We were doing pretty constant hand shears and pole tests to make sure we weren’t fooling ourselves. Conditions remained manageable and we reached the hut at our turn around time.
In the short time that it took us to have a snack and remove our skins the winds continued to accelerate and the precipitation rate was now a solid 1cm per hour. Brief intense gusts were now really beginning to move snow around. The headwall was now sluffing and we beat a hasty retreat with our group spaced out. The soft slabs were becoming more pronounced and more widespread but we were now out of harm’s way. We suspected that by morning the slope below the hut may even be a concern.
The large open slope directly above the entrance into the canyon (as you come down from the hut) was also distinctly different from the morning and we felt that by Saturday morning this would also be a more significant consideration. We felt it odd that even when we were breaking trail in untracked snow that we didn’t have any whumpfing today. Didn’t need it to tell us that the hazard was rising. We had far too many other indicators. Fortunately we made it in and out before things really started to get spooky.
As an aside, the creek in the canyon has a large number of open holes and it just doesn’t seem as well filled in as normal. The winds in the canyon were calm in the morning but had started to drift snow when we made our way out. The lake also had a “slushing event” (common during wind and snow events) and there was open water about 15cm below the surface snow. Managed to keep our skins and feet dry but a few unlucky “soles” hiking along were obviously not so lucky!
It was heartening to see that Parks had bumped the hazard to High/Considerable/Moderate for Saturday. Sure felt that things were heading that way to the group and me.
Cyril Shokoples MG
RescueDynamics.com
ACC AST2 Crew
Our ACC Calgary AST2 course went for a day trip to the Bow Hut today. By mid morning the west winds had already begun to pick up to moderate and light snow was falling at a rate of less than a centimeter an hour. At noon we ran into Nick’s group from Yamnuska descending from the hut and he mentioned that he felt soft slabs were already beginning to form.
We could see the snow starting to be redistributed in the rocks above and we decided to run up and down to the hut and see how good a track we could set and how safe we could be. We also felt the soft slab formation and a few isolated small features in the immediate lee of the wind were definitely beginning to behave like slabs. The final slope below the hut had some thin 10 to 15cm soft slabs that sheared very easily in isolated locations. We had already had the discussion that at the first sign of this becoming any thicker or more widespread we would just turn tail and run. We were doing pretty constant hand shears and pole tests to make sure we weren’t fooling ourselves. Conditions remained manageable and we reached the hut at our turn around time.
In the short time that it took us to have a snack and remove our skins the winds continued to accelerate and the precipitation rate was now a solid 1cm per hour. Brief intense gusts were now really beginning to move snow around. The headwall was now sluffing and we beat a hasty retreat with our group spaced out. The soft slabs were becoming more pronounced and more widespread but we were now out of harm’s way. We suspected that by morning the slope below the hut may even be a concern.
The large open slope directly above the entrance into the canyon (as you come down from the hut) was also distinctly different from the morning and we felt that by Saturday morning this would also be a more significant consideration. We felt it odd that even when we were breaking trail in untracked snow that we didn’t have any whumpfing today. Didn’t need it to tell us that the hazard was rising. We had far too many other indicators. Fortunately we made it in and out before things really started to get spooky.
As an aside, the creek in the canyon has a large number of open holes and it just doesn’t seem as well filled in as normal. The winds in the canyon were calm in the morning but had started to drift snow when we made our way out. The lake also had a “slushing event” (common during wind and snow events) and there was open water about 15cm below the surface snow. Managed to keep our skins and feet dry but a few unlucky “soles” hiking along were obviously not so lucky!
It was heartening to see that Parks had bumped the hazard to High/Considerable/Moderate for Saturday. Sure felt that things were heading that way to the group and me.
Cyril Shokoples MG
RescueDynamics.com
ACC AST2 Crew
Thursday, February 4, 2016
[MCR] Rockies: Bow Summit
Spent Day two of an ACC Calgary AST2 course at Bow Summit today. Saw some relatively recent avalanche activity in the major slide paths on Observation Peak, including the skier triggered avalanche reported previously. I have the feeling that despite the fact that the snow pack is not as reactive as it was a week ago there are still some big surprises lurking out there. Certainly a few folks have a higher risk tolerance than I do based on the location of some of the tracks on and beneath major features.
Made for interesting group discussions regarding risk tolerance and where to place your up track when avalanche hazard is Considerable. The fact that I find interesting is that the definition of the rating Considerable begins with the statement “Dangerous avalanche conditions...”
Be that as it may, we had time to do some quick compression tests below treeline and found the January 5 Surface Hoar down 25cm and the December Surface Hoar down 50cm in a snowpack that was around 100 to 120cm deep. We had failures in the moderate range in compression tests on these layers with some tests producing sudden results (pops and drops). Our extended column test did produce a failure in the moderate range but no propagation.
We postulated that this was due to the fact that where we were below treeline the snowpack was not stiff or cohesive enough to propagate. For example, the upper 25cm in our location was low density or soft snow that you could easily push your fist into (ie. fist resistance). Another 25cm beneath this and above the December surface hoar the snow allowed you to relatively easily push four fingers into it (4F resistance). We felt that if the snow above either of these two buried surface hoar layers was a bit stiffer, as you might find on an open or lee loaded slope, that it may be conceivable that the weak layer would fail and the fracture would propagate in a slab avalanche.
Looking around and doing a bit of digging didn’t inspire all that much confidence in me to ride the bigger features yet. I am probably going to still be fairly conservative, especially in light of the weekend forecast for more snow together with some wind. Things that make you go “Hmmmmm.”
Going touring again tomorrow. Ride safe!
Cyril Shokoples MG
ACC Calgary AST2 Group
Made for interesting group discussions regarding risk tolerance and where to place your up track when avalanche hazard is Considerable. The fact that I find interesting is that the definition of the rating Considerable begins with the statement “Dangerous avalanche conditions...”
Be that as it may, we had time to do some quick compression tests below treeline and found the January 5 Surface Hoar down 25cm and the December Surface Hoar down 50cm in a snowpack that was around 100 to 120cm deep. We had failures in the moderate range in compression tests on these layers with some tests producing sudden results (pops and drops). Our extended column test did produce a failure in the moderate range but no propagation.
We postulated that this was due to the fact that where we were below treeline the snowpack was not stiff or cohesive enough to propagate. For example, the upper 25cm in our location was low density or soft snow that you could easily push your fist into (ie. fist resistance). Another 25cm beneath this and above the December surface hoar the snow allowed you to relatively easily push four fingers into it (4F resistance). We felt that if the snow above either of these two buried surface hoar layers was a bit stiffer, as you might find on an open or lee loaded slope, that it may be conceivable that the weak layer would fail and the fracture would propagate in a slab avalanche.
Looking around and doing a bit of digging didn’t inspire all that much confidence in me to ride the bigger features yet. I am probably going to still be fairly conservative, especially in light of the weekend forecast for more snow together with some wind. Things that make you go “Hmmmmm.”
Going touring again tomorrow. Ride safe!
Cyril Shokoples MG
ACC Calgary AST2 Group
Wednesday, February 3, 2016
[MCR] Mallard Lodge, Canadian Rockies
Hi all,
We have been enjoying good skiing and a unique wilderness experience out of the Mallard Lodge for the last 4 days. This area is located just west of Jasper National Park. The height of snow at treeline in this area is about 145cm. The snowpack here is a typical continental snowpack with much thickness variation in the alpine. The upper 30-40 cm is supportive and skis very well at all elevations. It displays a nice hardness increase from fist to one finger plus snow. The mid-pack is faceted, softer and weaker. Snowpack tests on various aspects and elevations are producing moderate to hard resistant shears down 30-35cm and moderate to hard sudden shears down 45-75cm. The deeper weak layer is most likely the early January layer and consist of decomposed surface hoar to 5mm overlying a 10-15cm softer (one finger minus) faceted snow layer below. The lower snow pack is much firmer and appears stable at this time.
We have been skiing treeline and alpine terrain to 38 degrees with an emphasis on supported slopes. We have been experiencing lots of dynamic snowpack settlements (whumpfing) at all elevations however, none of them triggered avalanches. We have been avoiding convex slopes and exposure to overhead avalanche terrain. Today the ridge top winds picked up to moderate from the southwest and new wind slabs started to become a concern in alpine lee start zones. Cornice growth was significant today. We saw a few natural cornice falls and in one case a size 2 slab was triggered by a cornice fall. We also saw a natural size 2 in a cross-loaded slope at treeline today. Both avalanches appear to release on the early January weak layer down 45-75cm. Skiing is still really good in protected areas however, this may change with foretasted winds and warming trend.
Mallard Lodge is a great venue for folks looking interested in a small modern and comfortable lodge with varied and interesting terrain.
Regards,
David Lussier
acmg mountain guide
http://summitmountainguides.com/
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