Island Park

We were ski touring on the SW side of Mt. Henderson today, and noticed a large (natural?) avalanche on the NE aspect of Henderson.  First observed at around 1:15pm.  It appeared to be very fresh, possibly from a remote trigger this morning.  

2 photos attached.   A NE aspect, around 10,000'.

It looked to be 4-6' deep and about 500' wide.  And it failed on snow at/ near the ground.

Weather:  today alternated between heavy snowfall, and patches of sunshine.  Temps in the low/ mid 20's F, and calm winds.  A very nice day for ski touring.

No other avalanche activity observed in Miller Creek.

We experienced a couple of large collapses on westerly aspects/ in wind affected terrain around 10,000'.

From obs on 12/29: "On our way out near the cabin I cut a line close to a creek to see if I could trigger something."

From obs on 12/29: "On our way out near the cabin I cut a line close to a creek to see if I could trigger something."

We rode teepee sat morning. Pretty good snow but relatively baseless. Broke an arm so fixed and went up blue creek on the west side of IP down Yale Kilgore road. 
we went in about 3pm so it was warm and super dense fog up high towards reas peak. 
rode several draws southwest of the peak prolly about 8000 but could be wrong. 
as we got to the open areas it was already super trenched out and setting up fast forming a nasty ice layer that was everywhere. Open areas, in tight trees etc. 

it was setting up but also warm so kind of turning to corn snow but the ice layer was so thick and rigid it was audible over the sound of the sleds. If you stuck a leg in it wouod grab your leg etc and it was everywhere we rode. 
 

rode until dark then rode out. Seemed to be getting worse the later it got. 
 

heard from others that they experienced similar conditions in big springs. 
 

hope this is helpful :) pin is approximate 

Thick and robust ice crust layer widespread above white elephant.  Photo: Ride Rasmussen Style 

Riding in the vicinity of Fish Creek Trail. Conducted a snowpit, result, ECTX. Snow was stable in this particular spot, did not have enough time to conduct another snowpit. HS 115, melt freeze crust 6-8" below surface, SH at 75cm, facets approximate lower 1/3 snowpack, 2-3 melt freeze crusts in snowpack. Overall 2 cohesive slabs make up the snowpack in this particular snowpit, split by MFcr.  Also in the area signs of wind slabs on N, NE, E, and SE aspects. Airtemp -6C, moderate winds from SW, light snow, and OVC.

Thick and robust ice crust layer widespread above white elephant.  Currently 4-5” of fresh snow on top of crust. Currently snowing heavily with moderate winds SW with gusts.