Observation: NWAC Forecaster

All Observations

Basic Information

Observation Date:

February 27, 2022

Submitted:

February 28, 2022

Observer:

NWAC Forecaster - Josh Hirshberg

Zone or Region:

East North

Location:

Cutthroat creek (SW-N-SE. 2,600-6,800ft)

Recent Avalanches?

Yes

Cracking?

None Experienced

Collapsing?

Isolated

A natural loose dry avalanche, size D1.5 that occured on February 27th. 6,500ft WSW, Cutthrout creek.

a natural windslab crown (D1) with wind transport visible. WSW, 6,700ft, Cutthroat creek drainge

The northeast ridge of Hinkhouse peak in the foreground with Vasiliki ridge in the background. Wind features are visible from NE and SW winds on February 27th.

https://youtu.be/florqQKEp7U

Advanced Information

Wind:

Moderate , NE

New/Recent Snowfall:

35cm

Overcast skies and heavy snowfall tapering off by mid-AM followed by clearing. Locally moderate NE wind with strong gusts driving moderate to intense blowing snow through 12:00p. Then tapering and becoming more SW. Valley fog moved up valley from the east, reaching 5,500ft in Cutthroat ck by 3:30p

#	Date	Location	Size	Type	Bed Sfc	Depth	Trigger	Photos	Details
1	Feb 27, 2022 9:00 am ()	Cutthroat creek SE 6700ft	D1	SS-Soft Slab	I-New/Old Interface	1ft	N-Natural		Report

Map of listed avalanches:

Cutthroat creek

Avalanche Observation Comments:

Numerous small loose dry avalanches in the storm snow on most slopes 40deg and steeper. Mostly D1 but up to D1.5.
Natural wind slabs in the AM w wind loading. Activity may have continued into PM.
It appeared that most avalanches were running on the 2/26 interface.

Lots of new and recent light, low-density snow. Surfaces gained light cohesion where wind-stiffened, but mostly lacked slab qualities near and below treeline. On shaded slopes, 2/26 interface was very reactive in tilt test and avy obs. Minimal hardness difference made it difficult to pick out the interface. Notable test results on the late-Jan facets indicate propagation likely with enough loading. One small, localized collapse in a boulder-filled drainage around 5,000ft, NE.

Profile 6500ft, NNE
HS 310cm, HST 37cm
↓37cm 2/26 interface- easy tilt test
63-65cm 2/19 crust- CTM (RP), ECTN 20 ↓65cm
↓79cm Late Jan facets- (FCxr, 1.0-2.0mm), F+ hard, CTH (SC), ECTP 23, PST 30/100 END
See profile photo and graph for more details

Problem	Location	Distribution	Sensitivity	Size	Comments
Dry Loose	N E S W	Isolated Specific Widespread	Unreactive Stubborn Reactive Touchy	D1 D1.5 D2 D2.5 D3 D3.5 D4 D4.5 D5	Layer Depth/Date: 2/26
Wind Slab	N E S W	Isolated Specific Widespread	Unreactive Stubborn Reactive Touchy	D1 D1.5 D2 D2.5 D3 D3.5 D4 D4.5 D5
Persistent Slab	N E S W	Isolated Specific Widespread	Unreactive Stubborn Reactive Touchy	D1 D1.5 D2 D2.5 D3 D3.5 D4 D4.5 D5	Layer Depth/Date: 80cm Weak Layer(s): Jan 30, 2022 (FCsf) Comments: Recent loads may already be stressing this very weak layer. Expect this to potentially re-activate in the coming 24-48hrs