Avalanche

Grant Ridge

Cam JohnsonFlathead Range & Glacier NP
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Quick report

Cracking
specific
Collapsing
specific

A wet and soggy day in the Flathead. We stayed on trails and ridgelines to access upper elevations. Getting off-trail at low and mid-elevations right now is not recommended.

  • Rain turned to snow at 5000 feet. Wet and isothermic snow turned to dry snow at roughly 5800 feet.
  • We began to receive signs of unstable snow at the transition to dry snow at 5800 feet.
    • We got it all: audible collapses, shooting cracks,  and triggered small avalanches.
    • Large cornices failed with a simple poke of a ski pole.
  • NOTE: The shooting cracks and slabs we triggered broke surprisingly far back on the ridge. This was the type of hard slab that would pull into lower-angle terrain or far back on the ridge.
  • Slabs were hard (1 Finger) and 1 to 2 feet thick.

We kept slope angles low and gave ridgelines a wide berth.

Bountiful signs of instability. We triggered small avalanches, initiated surprisingly long shooting cracks, and had numerous audible whumpfs while traveling along the ridge.

Weather

Cloud Cover
overcast
Wind Loading
intense
Rain Elevation
5000
Recent Snowfall
12
Snow Avail For Transport
moderate amounts

Warm, wet, windy. 37 degrees F at parking lot. Rain turned to snow at roughly 5000 feet. Wind speeds gusted to "blow you over" force at upper elevation ridgelines.

Snowpack

We dug a snowpit at 6600 feet on a ESE aspect.

HS: 100cm. We found a buried layer of surface hoar and near-surface facets at 55 cm. The surface hoar was broken pieces and not standing upright. Other than that the snowpack really looked pretty good. 

Avalanche

Size
D1 R1
Type
HS
Aspect
E
Trigger
AS
Elevation
6300 ft

Triggered on test slopes. Triggered multiple hard wind slab avalanches