Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
February 15, 2021
Submitted:
February 15, 2021
Observer:
SAC - Scott Savage
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Boulders - Spring and Cherry Ck (RECREATIONAL day) (7100-9500', NW-W-SW-S-SE)

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
None Experienced
Collapsing? 
None Experienced

Snow Stability

Stability Rating: 
Good
Confidence in Rating: 
Moderate
Stability Trend: 

Bottom Line

We stayed on slopes below about 32* and did not get into alpine terrain or any wind-loaded terrain. Stability was GOOD where we were, unknown at upper elevations. Recent snow and wind had filled in the skin tracks above about 9000'. With 2-3" of new snow this afternoon and winds transporting snow above treeline, I would expect to find sensitive fresh wind slabs at upper elevations.

Advanced Information

Weather Summary

Cloud Cover:
Overcast
Temperature:
20s F road, maybe teens 9000'?
Wind:
Light , NW
New/Recent Snowfall:
2 inches (5cm) new snow at HWY 75 parking at 1400hrs.

Flurries and some sun until about 1500 hrs, snowing hard 1530-1700 with about 5-8cm (2-3") of low density new snow while we were out. Winds increased to moderate above 9500' (at 1600hrs, while it was snowing fairly hard/S3). There'a a fair amount of snow available for transport at the middle/upper elevation transition if the winds pick up.

Snowpack Observations

Steep solars (SW-S-SE): 1cm crust beneath about 5-12cm storm snow below 8500'. FC under the crust, then a mess of crusts + FC to ground. HS=40-70cm.
Below 8800' W-SW: HS=70-90cm, almost entirely F-4F FC below the new storm snow in shady locations, facetlanches (loose snow avalanches) could be possible in very steep, shady+sheltered terrain. Some thin crusts below the recent storm snow in sun-exposed areas.
Above 8800' W-SW: HS=90-120cm, not a pretty snowpack with plenty of weak snow below the recent storm snow. Not much of a slab on NW-W-SW sheltered, some harder wind-affected snow in places. Still finding spots where ski pen was to the ground while skinning uphill.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Persistent Slab
Isolated
Specific
Widespread
Unknown
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Comments: Location graphic shows where we traveled. Lots of weak facets still there, but not a lot of stiff snow (slab) above the facets in sheltered areas: I called the problem isolated because of this. Wind-loaded slopes (recent or previous) would paint a different picture.

Recreational day skiing with the family, so I did not perform any stability tests - just a lot of probing/pole probing/hand pits. Given the snowfall rates, snow available for transport, and noisy winds in the alpine, I feel confident there would be a wind slab problem there.

Terrain Use

We planned to stay off of all slopes steeper than 32* and all wind-loaded slopes steeper than 30* so we did not have to worry about snow stability today.