From text message: “I was out with a friend and his 2 daughters. We were east of Jefferson 8990’ elevation. East aspect ECTP 22. Down 78cm from surface. Melt freeze layer I would describe as breaking up?? garbage.”
All elevations in Island Park experienced heavy snowfall combined with high winds,this made for unstable wind slabs and cornices. Photo: K Allred
All elevations in Island Park experienced heavy snowfall combined with high winds,this made for unstable wind slabs and cornices.
We saw a handful of avalanches above treeline terrain that seemed to be wind slabs. However wind and snow had obscured them and I suspect there had been a lot more.
In the last five days, this area has received snowfall containing 4.5-5.3 inches of water which has settled to about 3 feet of new snow.
In the last five days, this area has received snowfall containing 4.5-5.3 inches of water which has settled to about 3 feet of new snow. Winds last sunday night from the southwest reached speeds up to 80 mph before easing, but then they blew from the north today.
We saw a handful of avalanches above treeline terrain that seemed to be wind slabs. However wind and snow had obscured them and I suspect there had been a lot more.
No cracking in the new snow and one possible collapse. Interestingly - My stability test scores had actually improved since Friday when there was less new snow. They broke and propagated just under a crust under the new snow. ECTP12's on Friday. ECTN & ECTP25 today. The reason is that they have been breaking on old, broken snowflakes....not facets.
Key points
We observed two very recent natural storm slab avalanches about a 1.5 feet deep. One of them entrained a significant amount of snow an ran a long ways.
