Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
March 17, 2021
Submitted:
March 17, 2021
Observer:
SAC - Scott Savage
Zone or Region:
Banner Summit
Location:
Copper and Banner Summit area (6900-8300': N-W-S-SE)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced
Stability rating: varied from very good to fair depending on aspect and elevation.

Snow Stability

Stability Rating: 
Good
Confidence in Rating: 
Stability Trend: 

Bottom Line

Lower and middle elevation slopes facing the sun (W-SE-S-SE) became mush/glop by 3 PM, and very steep slopes would have been suspect for triggering wet loose avalanches. A nice southerly breeze and cloud cover kept exposed upper elevation slopes in this area cool enough for good skiing+riding conditions (corn) and minimal wet avalanche hazard today (as of 3 PM). Brief observations of northerly lower elevation slopes indicated they were staying cool and did not pose wet snow hazards.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Cloudy
Temperature:
40s F
Wind:
Light , S
New/Recent Snowfall:
None.

Sky was clear in the AM, increasing clouds all day, mostly cloudy with some flurries and graupel by 3 PM. Temps were low 40s F at Banner Summit on the road, 30s F at middle elevations. Wind was steady light, gusting to moderate speeds.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Comments Photo
1 McGown Peak
E 9100
D1.5 WL N-Natural Also a fresh D1 to looker's right of the bigger slide.
Wet loose avalanches in alpine terrain on the east side of McGown Peak.
1 Gladiator Ck
W 9100
D1 WL N-Natural Several generations of WL in this area, seemed like one or 2 were quite fresh.
Several generations of small wet loose slides on a west aspect near the middle-upper elevation transition in the Gladiator Creek drainage.

Its getting hard to tell how fresh or old various wet avalanches are.

Snowpack Observations

HS Copper 6900-8300=110-180 cm.
W-SW-S-SE got sloppy (top 20cm, suction cup skiing) in wind-sheltered terrain below about 7800' by 3 PM. Sun-exposed lower elevation slopes below about 7500' were getting spooky - falling a little deeper into the snowpack on skis in isolated spots.
Shady aspects did not have wet issues today. Upper elevation S aspects stayed cool enough (nice supportable corn) by 3 PM, probably because of the steady breeze.

Terrain Use

We avoided W-SW-S-SE facing avalanche terrain below about 7800' once the surface softened significantly. We also stayed out of the northerly >38* terrain just above the highway (don't trust it given that it piles into a creek...).