Alud

Mid-day Middle Fork

FACFlathead Range & Glacier NP
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Quick report

Lots of blowing snow and plenty of thin, soft slabs of drifted snow near crossloaded, mid-elevation ridgelines.  Unreactive, except for one soft slab released on a ski cut. Cornice drops did not produce slides. We did not linger in the maelstrom of winds at the main ridgeline to investigate more exposed terrain. Stuck to sheltered, north through east slopes with short pitches of 30-35*. Very good riding on soft, settled, boot-top drifted and new snow. Snow profile and tests on a northeasterly slope at 6700 ft did not produce propagation or sudden shears under the wind slab, on a layer of graupel, or near the mid-January crust (~130 cm below the surface).

Weather

Air Temp
24
Cloud Cover
overcast
Wind Loading
intense
Recent Snowfall
5 cm
Snow Avail For Transport
moderate amounts

Westerly and southwesterly winds most of the day, reaching into valley bottoms at times. Gale-force gusts at ridgeline, with an hourish break mid-afternoon. Snow much of the day, S-1 to S2, pushing S5 briefly. Mostly heavily rimed precip particles that were not cohesive. Hard to tell how much fell because of moderate-intense blowing snow.

Snowpack

HS almost 300 cm on a northeasterly, leeward slope at 6700 feet. No concerning layers in the top meter of the profile, though wind slabs are probably reactive and dangerous where they're thivker and harder. A layer of graupel under a thin, decomposing crust was obvious in the pit wall, but not reactive. 

The mid-January ice/ crust was buried about 130 cm below the surface. I found a thin layer of facets above it that are starting to round. These did not fail in an ECT or Deep Tap Test, but the ECT column did shear off cleanly when we pulled/ pried on it after the test. Did not notice a soft layer of facets under the ice.

New snow covers a 1-5 cm melt-freeze crust below about 4500 ft.

Avalanche

Size
D1 R1
Type
SS
Aspect
N
Trigger
AS
Elevation
6000 ft

Cornices on mid-elevation ridge hard but reactive. Microwave- to fridge-sized cornice drops did not trigger any slabs in the soft, wind-drifted snow below. 1 soft released from a ski cut. No cracking or collapsing.