24-25

Snowboarder triggered wet loose slide in Bridgers

Bridger Range
Code
L-AS-R1-D1.5
Elevation
8800
Aspect
E
Notes

A snowobarder tagged us in an IG story of triggering a long running, powerful wet loose slide in the Bridger Range.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Loose-snow avalanche
Trigger
Skier
R size
1
D size
1.5
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Skier triggered wind slab on Saddle

Saddle Peak
Bridger Range
Code
AS-R1-D1.5-I
Elevation
9000
Aspect
NE
Latitude
45.79430
Longitude
-110.93600
Notes

From BBSP: " At 2.45?pm a... solo skier triggered a wind loaded pocket on the main face of Saddle Peak that ran down over the cliff and produced an impressive powder cloud.... I met him... and confirm he was alone and no one was in front of him. The avalanche looked to be 2' deep on the southern flank and 5" deep on the northern flank... It entrained more snow on the way down, one 2' deep downhill wind loaded pocket and some loose wet snow. It ran into the bottom of the going home chute, gouging a large hole and then 100ft downhill left a 200ft by 30ft wide shallow debris pile."

Number of slides
1
Number caught
0
Number buried
0
Trigger
Skier
R size
1
D size
1.5
Bed Surface
I - Interface between new and old snow
Problem Type
Wind Slab
Slab Thickness
18.0 inches
Vertical Fall
1200ft
Slab Width
100.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

From BBSP: " At 2.45?pm [Apr 5] a... solo skier triggered a wind loaded pocket on the main face of Saddle Peak that ran down over the cliff and produced an impressive powder cloud.... I met him... and confirm he was alone and no one was in front of him. The avalanche looked to be 2' deep on the southern flank and 5" deep on the northern flank... It entrained more snow on the way down, one 2' deep downhill wind loaded pocket and some loose wet snow. It ran into the bottom of the going home chute, gouging a large hole and then 100ft downhill left a 200ft by 30ft wide shallow debris pile."

Bridger Range, 2025-04-06

(Apr 5 ) "Observed multiple D1-1.5 natural dry loose avalanches (and some tiny wind slab pockets under the ridge cornice) that likely occurred during peak warming around 2-3 PM. North/sheltered aspects from ~9- 8.5k held an average of 8+ inches of dry, drifted snow...." Photo: G. Antonioli

Bridger Range, 2025-04-06

Reactive wind slabs, future wet snow hazards

Date
Activity
Skiing

We skied near Henderson Mtn. and Lulu Pass. Skies were clear with a light breeze near the ridgelines. Temperatures stayed below or just barely above freezing.

We saw a couple 3-6" deep natural wind slab avalanches and a few dry loose slides that looked to have happened within the last 24 hours. On southerly slopes below 9,000' there were some wet loose slides from yesterday afternoon. 

Wind slabs were still reactive today. We triggered 3 small, 3-8" deep x 5-15' wide, hard wind (1F+) slabs on convex test slopes well below the main ridgelines. 9,800', NE aspects. Also triggered one softer (4F) wind slab just below the high ridgeline, 10,200', NE aspect. 10-15' wide x 6-8" deep.

Snow stayed dry on northerly/shady slopes. Any sunny slopes got moist and had a crust formed by late this afternoon. We did not notice any fresh wet loose slides or roller balls on southerly slopes above 9,000'.

Stay alert for unstable drifts of snow, wind slabs formed last week are still breaking. Anticipate wet snow hazards to increase in size and distribution as the days get hotter this week.

Region
Cooke City
Location (from list)
Henderson Mountain
Observer Name
Alex Marienthal

N. Madison snow obs

Date

We snagged an early morning tour to avoid the heat today and it (mostly) worked. We saw no avalanches, cracking or collapsing while out. 

-We found a 2-4cm thick breakable crust on SE, S, SW, and W aspects that probably formed during Friday’s sunshine capping 6-10” of fresh snow above 9k’

-There was much less fresh snow below 9k’ (baked off?)

-Northerlies held stable soft snow!

-Small natural dry loose activity started around 11am on steep NE and E slopes initiating from around rocks/trees

-We sniffed out some south facing corn, but it was generally grabby/sloppy wherever a few inches of recent fresh snow remained

Region
Northern Madison
Observer Name
Zach Miller