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Wet Loose along GTSR
Location Name:
Going-to-the-Sun Road
Observation date:
Tuesday, April 27, 2021 - 12:00
Is this an Avalanche Observation:
Yes
Observation made by:
Public
Tabs
Quick Observation
High humidity and warm temperatures on Monday formed a thin fragile crust on the snow surface despite lack of direct sunshine.
Tuesday started sunny and below freezing.
New snow since last Thursday (12-16 inches above 6k feet) settled rapidly by noon forming a cohesive slab.
No change in PST scores/critical cut length at old/new snow interface over the course of 2.5 hours on east facing slope at 7200 feet. No change likely due to increasing cloud cover and lack of direct solar input.
Cloud cover limited natural wet loose activity but we observed around >10 D1 avalanches with 2 D2 avalanches by 2:00 p.m.
Snowpack, Avalanche, Weather Images:
Travel Details
Region:
Glacier National Park - McDonald Lake Area
Activity:
Skiing
Avalanche Details
Avalanche Details:
Date and Time of Avalanche:
Tuesday, April 27, 2021 - 12:00
Number of avalanches:
15
Avalanche Type:
Wet Loose
Failure Plane/Weak Layer:
New/old snow interface
More information or comments about the avalanche:
See Quick Obs. for more info.
Sizes up to size D2 and multiple locations (only identified one pin on map).
All occurred on steep upper elevation (>6500 ft.) slopes from cliffs/rocky outcrops/trees.
Occurred on E,SE,S,SW,W,NW aspects by 2:00 pm. Onset of D1 sized avalanches began around 11:00 a.m.
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
38
Starting Elevation:
above-treeline
Size
Destructive Size:
D1.5
Avalanche Location:
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