Friday, March 29, 2019

Hells today, Lust Avalanche.

      
From Joe, (the reporting party)

      Riding hells canyon today one skier one boarder came into 2.5 in between pride and gluttony. I came in a little low to a small ridge that is often wind loaded. Skier one was high and took the line to skiers right. We discussed me going one ridge over to avoid triggering the wind slab. As skier one cut right I moved about 8 ft to get a better angle for a video where I then released the wind slab. I quickly yelled to skier 1 and he stoped well out of the slide path. We then decided I would ride down where we regrouped and both agreed we had made a bad call in dropping in with the conditions. Skier one then skied down to a tree high in the cemetery on left hand side (out of slide path) were he stoped I road to him where we regrouped quickly to head out the exit. Within a few seconds of stopping “lust” or #1 avalanched above us. The powder cloud almost reached us and we could see a large slide running full track. After we both stopped shaking we made a quick exit feeling uneasy about what was above us. We saw no signs of anyone involved. We both knew the instabilities in the new snow and chose to thread the needle. Poor decision and far to close of a call for either of us. You can never be sure of what’s above you and today was not the day to push. Lucky to take this one as a learning experience. 


       From Ogden Avalanche.  Joe did the right thing and instantly spoke we ski patrol and reported the accident.  If he had not ski patrol would have responded to look for someone in the debris.  Please, if you see or trigger an avalanche around Snowbasin please report to Ski Patrol.





Monday, March 25, 2019

Surface Hoar close call.


From Reporting Party;

I was almost fully buried today on the skin up.  We knew that SF was a possible problem and were trying to avoid steep slopes that may have preserved SF.  We were skinning up a sub ridge when we collapsed the slope once.  My partner said "did you feel that"  I said "no" than the slope collapsed again and and avalanched.  My partner collapsed the slope. We were on the far right flank, I was breaking trail and my partner was not caught.  I tried to ski (with skins on) off the slab but could not gain enough speed.  I was caught and carried.  I tried to grab the first tree but could not hang on.  I grabbed the second tree I came to and hung on.  I was buried on the up slope side of a tree.  
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Surface hoar was the culprit we were headed to ridge walk and find an area to look for surface hoar and test it.  We found it.  Here are some photos.  We were being super conservative with route finding.  We had to go around a tree on sub-ridge and that is where we were caught.  This one is hard.  Could have gone left of tree onto east aspect but there were a couple rocks on a convex roll.  Just went with instinct I guess.


Red is Up Track, Yellow is how group planned to reach ridge.


Crown Depth between 24-30"




Ben Lomond Avalanche on March 21 and how we got to a myriad of avalanche problems.



      High Pressure set in for 7 days from March 14- March 20 during that time our snow surface faceted and we grew surface hoar on the snow surface.  These persistant grains were than preserved by the wind event on March 20-21 and buried even more with snow on Friday March 22.  We followed up with easy to trigger wind and storm slabs on Friday.  We now have added more weight (~2" of SWE ) and 16 inches of snow.  This will lead to interesting avalanche conditions today.

Surface hoar from last week.
Facet Loose Dry avalanches from last week


Avalanche from Friday March 22 failing on NSF and Surface Hoar


On Wednesday March 20 a party camped near Ben Lomond for the Spring Full moon.  They went to ski Ben Lomond head wall on March 21 and triggered this avalanche.  


From the party "We skinned it and set up camp at about 7:00pm. Camp was at about 8600 ft. We summited Ben Lomond at 1am skied the ridge down to our camp and then summited again the fallowing morning when this happened. The snow was very inconsistent with soft patches and hard patches that blended together so you couldn’t really see it to expect the sudden change. "  Instagram @shred_wards


Thursday, March 21, 2019

From Reporting Party


"We skinned up out of Porkies and cut across the top of Malan's, which showed signs of lots of wet, heavy slides from the previous warm days.  The surface was hard, bonded, and concrete.

We made out way down the ridge separating Malans from Taylor Canyon and decided to drop in east of the burn.  We skied down the south side of the ridge in hard, but slightly softening snow until we made it around the major rock outcrops.

We skied over the ridge and decided to ski into Taylor Canyon. We made 6-8 turns in gorgeous wind deposited powder snow above the trees, then cut one or two hundred yards west through dense trees to a more open area on the top of our run.

We skied one pitch down a wide area that narrowed into a gulley 150 feet east of where I would eventually slide.  We took turns and once my partner was down with me in the trees, I cut to the west looking for another line to ski out of the funneling gulley.  We cut west in an open area fifty feet above more closely spaced trees.

I stopped when I saw a gap to ski.  I turned to tell my partner I was skiing the gap when he yelled that I was sliding.  It broke above and around me and slowly started to move.  I was quickly knocked off my feet.  I deployed the airbag, and while the slide was moving relatively slowly I hoped to grab a small tree, but as it accelerated through the gap I just tried to avoid the trees. My skis stayed on for the entire slide.

The slide spilled out into the major ravine and turned left.  It slowed down in this ravine, and while it ran quite a ways down the drainage, I was able to come to a stop on the edge of the drainage.

I told my partner on the radio that I was fine and he cautiously skied down to me.  I deflated my airbag, gathered one pole.  We continued down and out the canyon.

Lessons - 
1. While the avy danger is low, and these dangerous pockets are scarce, we were in very high consequence terrain with 35+ degree slopes and trees.  We should have continued farther down to the burn and skied lower angle areas.
2. We were prepared and worked well as a team - proper spacing, skiing one at a time, talking about the dangers, slope angle, aspect, etc.  Our beacons were on and my ABS bag was armed.  This all helped mitigate what could've easily been a worse situation.
3. My partner was very surprised about the slide and unsure what to say.  He thought the slide might just be sluff.  His call is what let me know for certain that I was caught in a slide.
4. The slide was absolutely silent.
5. Proper spacing between us kept him from being caught in the slide, too.
6. The radios were critical and I was able to let my partner know I was uninjured and not buried.
7. I remained calm during the ride, but during the last half of the ride it would've not been good if I hit a tree.  That's what was really on my mind after the bag inflated.
8. Good thing I had the instruction card for the ABS or I wouldn't have known how to deflate it.  (We looked pretty silly reading instructions over an inflated bag). "


 From Ogden Avalanche
          My best guess; this was a newly formed windslab from yesterdays (3/20) heavy winds.  The wind slab appeared to have failed on the NSF (Near Surface Facets) or Surface Hoar that have formed in areas like this over the past week with cold clear nights.  These avalanches will be pockety in areas that are protected.  This was a small wind slab (30' wide) that could not burry a person but a scary ride none the less.   The  party was carrying avalanche rescue gear and was practicing safe travel protocols.  This helped only one person get caught and they were able to ski away.  

A similar accident occurred in Stairs Gulch of BCC (SLC) yesterday.  Link (https://utahavalanchecenter.org/avalanche/46181)