20-21

Natural avalanche on Woodward Mountain

Taylor Fork
Southern Madison
Code
HS-N-R3-D3-O
Elevation
10400
Aspect
E
Latitude
45.01260
Longitude
-111.41300
Notes

We saw this crown while riding in Taylor Fork on 1/31/21.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
3
D size
3
Bed Surface
O - Old snow
Problem Type
New Snow
Slab Thickness
48.0 inches
Slab Width
1000.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Natural and snowmobile triggered avalanches in Taylor Fork

Taylor Fork
Southern Madison
Code
SS-N-R2-D2-O
Aspect Range
E, NE, N, SE
Latitude
44.96450
Longitude
-111.33400
Notes

GNFAC forecaster were in Taylor Fork on 1/31/21: There were many small(er) pockets R2-D1/2 along the northeast facing ridge of Carrot and Sage Basins. Some looked like they broke below the new snow or on surface hoar, and some broke deeper to the facets at the ground. We dug a pit above one of the crowns that and got an ECTP16 on surface hoar 40 cm down, and ECTN 29 on the depth hoar. PST 37/120 end on the depth hoar. HS 150cm. 

Also numerous slides in Lightning and Beaver Creeks in the Wilderness. Also noticed a large crown in Sunlight Basin spanning across the lookers left half of the heavily wind-loaded/corniced bowl. R3-D2/2.5 probably, 500’+ wide

Number of slides
4
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
24.0 inches
Vertical Fall
100ft
Slab Width
150.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

Divide/Hyalite

Date
Activity
Skiing

I toured around the upper end of Hyalite creek with a couple friends. On the way up, we observed point release sloughs that were larger (up to 30’+ wide) and ran longer than I can remember seeing in recent memory. None stepped down to anything, or gave the appearance of forming a slab.
Our first stop was Divide Peak. Two very large sloughs had run down the main south face with no results, so we felt good about the snowpack. We dug on a south aspect at about 9400’, and found 160cm of snow. The newest snow did not propagate in an ECT, but we had a failure ~40 cm down (maybe 1/17-1/18 snowfall) at ECTP18, and then on the depth hoar at ECTP22. We turned around.
The next stop was the west-facing chutes near Hyalite Lake, since I had not been on anything on that aspect yet this season. At the base of the slope, we found a highly variable snowpack, with very large-grained facets in shallower areas. A pit at 9200’ had HS 155 and ECTP28, failing with a poor quality shear on large, loose facets 60-65cm from the ground. We turned around there, too.
The base of the snowpack seems to be getting more cohesive as time goes on, but the process has been very slow and the starting point was dismal. We observed dozens upon dozens of sloughs and no activity beyond the new snow, but I do not trust this snowpack. As the wind picked up in the afternoon, it transported a great deal of snow near the ridgelines.

Location (from list)
Hyalite Peak
Observer Name
Sam Reinsel