Pro Field Report

Basic Information

Observation Details

Observation Date:
March 26, 2021
Submitted:
March 26, 2021
Observer:
SAC - VandenBos (off duty)
Zone or Region:
Sawtooth and Western Smoky Mtns
Location:
Profile/Fishhook (6,500-10,600', all aspects)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
Isolated
Collapsing? 
None Experienced
Cracking in new snow, in both wind-affected and largely sheltered areas.

Bottom Line

New snow was not bonding well to the old surface.

Media/Attachments

Advanced Information

Weather Summary

Cloud Cover:
Mostly Sunny
New/Recent Snowfall:
3-4cm on moraine, 15-30cm at upper elevations, really hard to gauge with confidence. Snowfall seemed variable even within individual basins

Cloud deck hanging at 10,000' around sunrise, clearing rapidly by 10. Light to moderate winds blowing at upper elevation for much of the day. Temperatures remained cool, despite intense solar gain. Cloud cover built during mid-afternoon but cleared again towards sunset.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Comments Photo
2
SW 9,800' 		D1 SS I-New/Old Interface AS-Skier
r-Remote 		Remotely triggered two small pockets (less than 50' wide each) that picked up a good bit of speed and snow on the descent, and flanked out where possible. Debris piles weren't huge, but would've taken you for a high-speed ride. Triggered from 100-150' away.
The two thin avalanches in the center of the photo were remotely triggered from over 100' away. Sawtooth Mountains, 9800', SW.
1
S 10,300' 		D1 SS I-New/Old Interface AS-Skier
c-Intentional 		Ski cutting produced a 80-100' wide slab near ridgeline that didn't run particularly far, due to the terrain.
Small wind slab triggered with a ski cut in the Sawtooth Mountains. 10,300', S.

Snowpack Observations

New/old interface was pretty reactive, even in areas without much of a sensible slab. Observed a dozen or so D1s that had failed during the storm at some point. Remotely trigger two D1.5s in terrain that hadn't seen more than a kiss of wind on a W/SW aspect at 9,800'. In general, these slabs seemed to be more common where associated with crusts but were present in shaded terrain as well. The initial pulse of loose snow activity went off this morning, with most obvious runners having already gone by noon. These slides were more of the solar-initiated dry loose variety. Plenty of ammo for larger wet loose slides with warmer temperatures, suspect we will see some of that in the coming days.

Avalanche Problems

Wind slabs were a clear problem, but new snow was quite touchy even in sheltered areas, particularly where associated with crusts.