montoya 0 Posted January 22, 2007 Share Posted January 22, 2007 for anyone interested, there were 3 separate avies in the bc around kagura this Jan 20-21 weekend: *Jan 20, caused by skier, soft slab, East face on Karagamine course, 50cm depth 100meter wide, 25-degree slope. looks like new snow from Jan 19 on top of Jan 16 surface hoar *Jan 20, caused by skier, soft slab, East face on a bowl behind Nakaone, 20cm depth 50meter wide, on steep convex rollover, starting zone probably 35-degrees *Jan 20/21?, looks like a cornice dropped, soft slab, South face just above #5 Kagura Romance lift, 20cm depth 50cm wide We did a quick compression test before dropping in a south-slope (1800m) on Sat, result was Moderate/15 taps/shear at 30cm Link to post Share on other sites
Fattwins 0 Posted January 22, 2007 Share Posted January 22, 2007 nice montoya Link to post Share on other sites
SerreChe 2 Posted January 24, 2007 Share Posted January 24, 2007 I saw one of these avalanches on the 20th, missed the other 2 (maybe on the 21st?). Saw a few lone skiers on their own riding fairly unsafe terrain on the 20th... Link to post Share on other sites
montoya 0 Posted January 24, 2007 Author Share Posted January 24, 2007 got the pics from some friends, here they are in order as listed above: Anyway, I think the snowpack is trickier than last year. At least last year you had big glide cracks that were pretty obvious. This year we are seeing lots of surface hoar and crust layers. Even Nakaone will slide, given the right conditions. There were +100 people in the bc both Sat/Sun, lots of tours and newbies and people who usually go to other areas (eg Arai) and now come to Kagura instead. Given the numbers, I think it's just a matter of time before we see some big accidents. Link to post Share on other sites
jgraves 0 Posted January 24, 2007 Share Posted January 24, 2007 Thanks for the info. Your second to last comment reminded me of an article I came across last year in Japanese about glide cracks. If memory serves, it was saying that glide cracks were the result of slow movement and didn't make catastrophic failure any more or less likely to happen. I think they were saying that it had something to do with sasa bamboo ground cover. Link to post Share on other sites
SerreChe 2 Posted January 24, 2007 Share Posted January 24, 2007 The 3rd one looks pretty fluid. Kagura was warm on that w/e, looks like the snowpack has gone through quite a transfo recently (sun + heat + wind). Just out of curiosity, when was the last accident on the Kagura sector in recent memories? I have seen a pic from Montoya in the past on SJ of Nakaone sliding almost all the way to the restaurant... Link to post Share on other sites
montoya 0 Posted January 24, 2007 Author Share Posted January 24, 2007 I haven't heard of any recent avie fatalaties at Kagura. However, I think 2 years ago, someone died on the winding genzan-course from Mitsumata down to the parking lot, he hucked off the course-side, landed upside down and suffocated in deep snow. If you want to go way back in time, there are the 4 yama-skiers who I think 50 years ago (before the Kagura ski-resort was created) skied down Bosawa in Jan or Feb, couldn't make it back up and died of exposure in a blizzard. Quote: Originally posted by SerreChe: The 3rd one looks pretty fluid. Kagura was warm on that w/e, looks like the snowpack has gone through quite a transfo recently (sun + heat + wind). Just out of curiosity, when was the last accident on the Kagura sector in recent memories? I have seen a pic from Montoya in the past on SJ of Nakaone sliding almost all the way to the restaurant... Link to post Share on other sites
tsondaboy 0 Posted January 24, 2007 Share Posted January 24, 2007 Didnt nakaone slide last spring also? Link to post Share on other sites
tsondaboy 0 Posted January 24, 2007 Share Posted January 24, 2007 Going back to the picks I took last Sat, I found some that might represent the conditions under which these avalanches occurred. It seems that there has been some serious meltfreeze going on the days before the snowfall and also there was some rain. You can clearly see the ice on the trees and above it the fresh snow that followed later on in the week. Also from the second tree you can see that there were some South winds blowing during the snowfall (the picks are taken facing more or less towards east). So that would probably mean that the North slopes would be wind loaded on top of a meltfreese crust. Remember talking about it at the top of Nakaone last weekend and the desision was to stay on the Nakaone although it was heavily tracked that is Southfacing and was on the windward side. Link to post Share on other sites
montoya 0 Posted January 24, 2007 Author Share Posted January 24, 2007 not that I can remember.. if you have any pics, would be interested to see. Link to post Share on other sites
tsondaboy 0 Posted January 24, 2007 Share Posted January 24, 2007 No I don’t have any, wish I had. I was also told about it from one of the older guys at the resthouse. My last day last season was in March, way before spring. Link to post Share on other sites
montoya 0 Posted January 24, 2007 Author Share Posted January 24, 2007 looking thru my notes this is what I have for that week: 16th clear skies/extensive surface hoar 17th fog (according to a friend) 18th fog -> snow (according to a friend) 19th 30-40cm new snow I don't think there was any rain during this particular cycle. I'm thinking that there was some melt from the fog/greenhouse effect on the 17th and 18th. this could account for the crust we found on the 20th beneath the new snow. Link to post Share on other sites
tsondaboy 0 Posted January 24, 2007 Share Posted January 24, 2007 Do you also have a record of the weather conditions from Sunday up to today montoya? I wanna do a fast pit next weekend, but befor that I would be interested to know what the contitions were and if I can predict before I dig it what I will find. Link to post Share on other sites
montoya 0 Posted January 24, 2007 Author Share Posted January 24, 2007 nope, too busy with work so no data this week. best bet is to follow the weather reports on sj.com, Yahoo! and WeatherNews, and check the live-cams for Naeba, etc. Link to post Share on other sites
tsondaboy 0 Posted January 24, 2007 Share Posted January 24, 2007 Yap I do that anyway, thanks. Link to post Share on other sites
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