There was an Avalanche incident on the Eastern flanks of Strata Mountain at 1300hrs on the 8th of January. A party of 4 was ascending out of trees into open terrain around 1350m when a small (size 1-2) avalanche released above them.  The depth was approximately 25 cms deep. The width of the fracture line was hard to see due to darkness. One skier was caught in the debris flow and taken over a 9 meter cliff (Approx.). The skier landed in open terrain and was swept an additional 30 meters. The skier caught sustained lower leg injures just above the boot top.  This forecaster and the Comox Valley Search and Rescue Team located the group at approximately 9pm. A decision was made to airlift the patient out and the 442 squadron out of Comox was dispatched.  Weather and winds hampered the rescue but the weather improved rapidly through the night and the patient was airlifted to Hospital at 3am.

The party was equipped with self rescue gear and were adequately equipped for travel in the backcountry. There was a mix of experience levels within the group but they were mostly experienced tourers with many miles of ski touring behind them.

Many thanks and Kuddos to the Comox Valley Search and Rescue Team and the 442 Squadron out of Comox. Were are very lucky to have these resources close to home. They made a difference last night as they do many times throughout  the year.

Points to take away from this incident:

Small avalanches can have serious consequences in relation to terrain traps.

Be cognizant of what danger ratings mean.

If you are a backcountry skier you need to take a first aid course.

Equip yourself for self rescue and always bring enough gear to get through a night. Even if its just matches and a saw and light bivy/tarp. Learn survival skills for winter environments.

Published by: Cliff Umpleby

Date: Saturday, 18 February.

Time: Approximately 10:30 AM

Location: West Bowl Mount Cain, Main Gully, skiers left hand side at first rock outcrop on skiers left in descent.

Elevation: 1450m

Aspect: NW

Slope Angle: approximately 32-33 degrees.

Trigger: Skier accidental.

Size: Estimated as size 2 (Could bury, injure or kill a person. Approximately 100 tons of snow).

Fracture height: 10cm to 80cm.

Fracture width: Approximately 40-50m.

Failure plane: Persistent crust/facet.

Distance ran: full path, approximately 300m.

Bulletin hazard rating on the day: Alpine: Considerable, Tree line: Considerable, Below tree line: Moderate.

Bulletin Main Concerns on the day: Wind Slab, Persistent Slab.

Description:

The skier was part of a group and descended on his own while the others waited above. He skied in under the first rock out crop on the skiers left on descent of the main gully feature. The fracture initiated there and quickly propagated skiers left for 40-50m. The skier fell immediately and rode the full length of the avalanche to near the trees at the bottom of the run out. He sustained no injuries but was partially buried and lost his skis.

Notes:

Two other avalanches where observed adjacent to this area.

The first was triggered about thirty minutes previously in the adjacent “Sliders” feature to the skiers left of the main gully when a snowboarder entered from above. Second hand reports state that the snowboarder sustained facial injuries when he hit a tree while being swept down by the avalanche. Estimated size: 1.5 (Between relatively harmless to people and large enough to bury, injure or kill a person. Between 10 and 100 tons of snow.).

The third avalanche was a natural release that happened around mid day the same day further skiers left in the sliders feature. This appears to be the largest avalanche of the day in the west bowl estimated at size 2.5 and running the full length of the path. Mid day was about the time that temperatures spiked to near zero at tree line that day.

Information for this report was compiled from interviews with the person involved in the main gully avalanche and two others who made observations.

One persons account of some of the incidents that day can be found at http://citizenclass.cp-sms.biz/entries/snow/near-death-experiences.

Summary:

Large natural avalanche (likely about size 3) on NW through W aspect in the Able Bowl in the Mount Cain area on Friday 18 March, 2011. No humans involved.

Details:

A large avalanche of note occurred in the Mount Cain area on Friday 18 March with details having come in only Tuesday 22 March, 2011. The slide took place some time in the afternoon on that day with an estimated 700-900m wide fracture line that spanned from NW through to W aspects in the Able Bowl below the true and false summits of Mount Able. The fracture line was about 200m below ridge line and was estimated to be between one metre and four metres in height. The avalanche ran the full path to fill the bottom of the bowl with deep debris and almost spilled over into the main east bowl drainage below the east bowl. One local described it as the largest avalanche he had seen in the Cain area in twenty years of skiing the area. The cornice above the slope was said by a number of observers to remain in tact meaning a cornice trigger was not the cause. Wind loading which had been happening for many days previously and continued on Friday is the probable trigger. The failure may have been wind loaded snow on the previous surface, or the failure may have been on our February crust layer deeper down. Further investigation is required.

This avalanche bulletin had the hazard in the alpine at CONSIDERABLE on that day. The part of the definition of this hazard rating under the "Likelihood of Avalanches" heading is that "natural avalanches are possible and human triggered avalanches are likely". This incident is a very good illustration of why it is so important to also make careful note of the "Avalanche Size and Distribution" descriptors in the Avalanche Danger Scale.  At a CONSIDERABLE rating this definition reads "small avalanches in many areas or large avalanches in specific areas or very large avalanches in isolated areas". Clearly there was a very large avalanche in an isolated area on this day. I mention this because it is important for users of the bulletin to recognise that even when hazard is dropping because natural avalanches are less likely and larger triggers may be required to start avalanches, large avalanches are still possible. It is important to read and understand all of the aspects of the hazard definitions (Likelihood of avalanches as well as size and distribution) and to read all of the details in the text of the avalanche bulletin and to apply them correctly to the terrain. We must not become complacent as hazard ratings drop.

It is also interesting to note that this forecaster departed from the Mount Cain area on that day likely within hours of the event, with a feeling of trepidation for what might happen at the mountain that week end. The wind had been blowing hard for most of the previous five days and slabs were fat and well primed for triggering while the wind continued to load. Additionally the wind was forecast to drop with a possibility for improvement in the weather and a big group of spring break skiers was arriving. This is the stuff that we forecasters can lose sleep over!

Reported by VIACS forecaster Jan Neuspiel with information from Cain local Cyril Douglas and observer Jim Stepan. Photos and further details to follow.

Skier triggered slab in the north bowl at Mount Cain.

The slab pulled out on a NNE aspect at about 1600m when the skier was two or three turns into skiing the line. The skier narrowly missed being swept over cliffs and lost equipment which was later recovered. There were no injuries or burials though the skier went for a fairly long ride. The slab was approximately 15-20m wide and perhaps about 30-50cm deep. It ran for about 200m. This avalanche bulletin had the hazard at moderate in the alpine and tree line for that day with a caution about triggerable wind slab. Photographs to follow.

Saturday 27 November, 14:00hrs. Skier triggered avalanche West Bowl Mount Cain, 1500m (tree line), West aspect, size 2.

A group of three skiers in the "Door Number Three" feature in the west bowl of Mount Cain were involved in a size two avalanche which resulted in one injured person and a lost ski.

The avalanche was triggered by a single skier high in the start zone, about 10 metres below ridge line in a soft slab on an unsupported feature. The fracture line was approximately 40 meters wide with a depth of 70 to 130cm. It is speculated that the slab was the result of both cross loading from North winds during our recent cold/clear spell and more recent storm winds. As the avalanche ran down the path a "step down" fracture occurred on a deteriorating crust which sits below all of our new snow since 17 November. This crust became soft and somewhat faceted during our cold, clear spell. The avalanche scoured out snow nearly to ground as it proceeded down the path.

The person triggering the avalanche rode with it the full length of the avalanche path (approximately 400m) hitting small trees as he went. The result was some bad bruising and ligament damage to the victim. The two other skiers were situated on a prominence to the skiers left of the path a short distance below the start zone. One of the two was torn from his stance by moving snow and rode for about 5 to 10 meters before grabbing a tree to stop. This person lost a ski. The other person stayed in their position.

Snowmobilers triggered a size 2 wind slab at 1800 m SE aspect on Jutland Mountain in Strathcona Provincial Park. The Wind slab was 1 meter deep and reported to be 50 meters wide. One machiner was decending onto the slab while a second was climbing up it when it released. The climber mangaged to climb through and on top of it while the descender escaped to the side. No injuries or burial were reported. The avalanche was formed by strong Northerly winds that redistributed cold Northerly and faceted snow into South and South East Aspects.  The slab was quite hard. I measured a slab in a safe place on Mt washington on the same day and it was 35% water content or 350 kilograms per cubic meter. The bed surface would likley have been a pencil hard crust. This was reported to me second hand by cell phone from the site to one of my students and the names and other information were withheld. Submitted by Niko Weis