Northwest Avalanche Center

Observation: Public

All Observations

Observation Details

Name:
Jeremy Jones
Observation Date:
February 4, 2023
Submitted:
February 4, 2023
Zone or Region:
West South
Activity:
Skiing/Snowboarding
Location:
MRNP Castle

Signs of Unstable Snow

Did you see shooting cracks? 
Yes, Isolated
Did you experience collapsing or whumpfing? 
No

Observations

Rain transitioned to snow @ 4150’ on the drive in. Moderate snow and generally calm winds all day, with some moderate NNW winds at ridgeline.

Near treeline in the open bowl below Castle featured stiffer snow. Stepping out of the skinttack @5800’ and stomping on a test slope yielded isolated shooting cracks (see photo).

A pit at 6175’ on a NNW aspect below the ridge just E of Castle showed 7cm of new snow over increasingly firm snow below. Tests yielded consistent failures on a layer 38cm deep, CTM(15) SP, CTM(20) SP. Compression test photo attached. Did not see the large facets at this layer I expected based on obs last weekend, seemed more like 2mm faceted rounded particles.

Media

Cracks in wind slab pocket on test slope
Pit profile
Results of Compression Test. Failed 38cm down on 15th hit, clean planar fracture Replicated results, with fracture on 20th hit.
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