Photos

From an email:

"We did observe a natural slide at around 8300ft that failed on the high pressure facets that formed prior to these last two shots of snow. It appears that it was triggered by a slough from steeper, rocky terrain above, the crown was about 14 inches deep and around 50ft wide, in complex rocky terrain. The debris pile was approx. 200cm deep, plenty deep to bury a person."  Photo: A. Pohl

The new snow and wind formed wind slabs on Mt. Blackmore that were cracking. Photo: B. VandenBos

Winds blew the new snow around. Ripples on the snow surface are evidence of wind slabs. Photo: B. VandenBos

Snow water equivalent at SNOTEL stations in the GNFAC advisory areas for the 18-19 season to date. Weak layers formed on the surface of the snowpack during the dry weather (flat section of lines), then they were buried by the recent 10-14" of snow (steep increase at end of graph). Image: GNFAC

Skiers saw this natural avalanche near Mt. Blackmore on Saturday (11/24). Almost a foot of new snow fell and buried weak snow that formed on the surface of the snowpack during cold and dry weather. Be cautious of avalanches breaking at this weak interface for a few days and with the next storm. Photo: M. Staples

Wind is moving snow creating wind slabs on the east face of Blackmore up Hyalite. This avalanche was seen on Thanksgiving. More snow and wind will create more wind drifting and more avalanches. Photo: B. VandenBos

A layer of surface hoar is on many slopes in Cooke City. These feathery crystals can be unstable when buried. We will be keeping an eye on them with the approaching storm. Photo: GNFAC

Alex Marienthal stands by the Lulu Pass weather station outside Cooke City. We put it up today and you can view the hourly data HERE.Photo: GNFAC

The surface snow is feathery crystals of surface hoar and small facets. These crystals are weak and will become unstable once buried. Today's snow surface may be tomorrow's problem. Photo: GNFAC

Plenty of traffic on Blackmore since the last storm. No signs of instability for now, but we did find near-surface facets and surface hoar on some slopes. This will be something to watch out for with the next storm, and they should be easy to identify in snow pits and stability tests. Photo: GNFAC

From BSSP: "There has been some significant surface hoar observed at treeline and below.  It is not melting and light to non-existent winds are allowing it to persist for now.  The attached pic is some of the biggest SH observed." Photo: BSSP

Winds during the snow storm on Friday rippled the snow surface up Hyalite. This is a clue that the snow drifted and loaded high elevation slopes. Photo: G. Antonioli

Winds over the weekend are growing the Bridger Range's cornices. Photo: T. Hoefler

Feathery crystals of surface hoar are seen on Mt. Blackmore in Hyalite. These crystals can be notorious weak layers once buried, but only time will tell if they survive until the next snowstorm. Photo: Z. Tondre

A snowmobiler triggered this small wind slab near Lulu pass outside of Cooke City. Wind loaded slopes are primary avalanche concern across the advisory area. Photo: J. Temple 

Strong winds in the Bridger Range formed dense slabs on leeward slopes. Yesterday, A skier north of Bridger Bowl triggered multiple wind slabs near the top of Wolverine Bowl. The skier turned around and chose a safer objective. Photo: S. Whitefields 

Climbers triggered this very small wind slab on the way to a climb up Flanders in Hyalite (11/11). A tiny slide to a skier can be bad news for a climber since losing one's balance or getting pushed off a cliff can be deadly. From an email (edited):

Photo: S. Magro

From an email:

"By and large right side up snowpack. Some small facets below the 11/1 ice crust at the ground, but well bonded snowpack overall. Pit observations consistent with hand pits dug throughout the day touring north out of Bridger Bowl." Photo: M. Zia

From an email: "ECTP 5 at the top of a chute on the south face of the Texas Meadows knob. Propagated on a layer 15cm from the top of the snowpack." Photo: J. Zimmerer