18-19

Y.C. explosive triggered slide

Yellowstone Club
Northern Madison
Code
HS-ABc-R2-D2-G
Elevation
7280
Aspect
NW
Latitude
45.22980
Longitude
-111.41200
Notes

"The YC Ski Patrol conducted avalanche mitigation work above another one of our roads today. The area is outside of our ski area boundary and receives no skier traffic. A 4lb explosives charge was detonated from an aerial tram and triggered a R2/D2 avalanche that ran to the ground. The crown was 2', the path width was around 100', and it ran 350 vertical feet (crossing the road) to the bottom of the runout zone. The elevation was 7280' on a NNW aspect and max slope angle of 34 degrees. Other sections of this slope were tested with explosive charges, yielding only black holes." Photos and observation courtesy YC Ski Patrol.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
An explosive detonated above the snow surface (air blast)
Trigger Modifier
c-A controlled or intentional release by the indicated trigger
R size
2
D size
2
Bed Surface
G - Ground
Problem Type
Persistent Weak Layer
Slab Thickness
24.0 inches
Vertical Fall
350ft
Slab Width
100.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

"The YC Ski Patrol conducted avalanche mitigation work above another one of our roads today. The area is outside of our ski area boundary and receives no skier traffic. A 4lb explosives charge was detonated from an aerial tram and triggered a R2/D2 avalanche that ran to the ground. The crown was 2', the path width was around 100', and it ran 350 vertical feet (crossing the road) to the bottom of the runout zone. The elevation was 7280' on a NNW aspect and max slope angle of 34 degrees.

Northern Madison, 2019-03-04

"The YC Ski Patrol conducted avalanche mitigation work above another one of our roads today. The area is outside of our ski area boundary and receives no skier traffic. A 4lb explosives charge was detonated from an aerial tram and triggered a R2/D2 avalanche that ran to the ground. The crown was 2', the path width was around 100', and it ran 350 vertical feet (crossing the road) to the bottom of the runout zone. The elevation was 7280' on a NNW aspect and max slope angle of 34 degrees.

Northern Madison, 2019-03-04

Multiple Naturals, Fan Mountain

Fan Mountain
Northern Madison
Code
SS-N-R2-D2.5-O
Elevation
9600
Aspect
NE
Latitude
45.29760
Longitude
-111.52400
Notes

Multiple natural avalanches released on Fan Mountain in the past few days. Some of the smaller slides were confined to the new snow, while two larger slides broke on deep persistent weak layers an ran a long distance. Photo: M. Delguidice

Multiple Avalanches
Number of slides
3
Number caught
0
Number buried
0
Number killed
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
2
D size
2.5
Bed Surface
O - Old snow
Vertical Fall
1500ft
Slab Width
300.00ft
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

Multiple natural avalanches released on Fan Mountain in the past few days. Some of the smaller slides were confined to the new snow, while two larger slides broke on deep persistent weak layers an ran a long distance. Photo: M. Delguidice

Northern Madison, 2019-03-03