Widespread Wind Redistribution

Map for Mountain Information Network report: Widespread Wind Redistribution

Information

Avalanche date/time
Wednesday, January 10, 2018 at 13:00
Estimated occurrence time of avalanche
Less than 12 hours ago
Number of avalanches in this report
1
The size of avalanche
1.5
Slab thickness
15cm
Slab width
25m
Run length
100m
Trigger type
Skier
Trigger subtype
Accidental
Start zone elevation
1,550m
Start zone incline
32°
Crust near weak layer
No
Wind exposure
Cross-loaded slope
Vegetation cover
Open slope

Comments

Came across a skier-triggered windslab today. Skier was fine, standing nearby, as was his partner. I did a little digging at the edge of the crown. Interestingly, the Friday rain crust was about 60cm down in this location. The crown was a stiff (crusty on the surface) wind slab that entrained a couple inches of more unconsolidated snow from below. Under that, I was surprised to find a layer of facets and then another more consolidated layer above the crust.

In the attached picture, I've dug out the area down to the crust. You can see the faceted layer underneath the surface slab, and the more consolidated snow underneath.

Skied across most polar aspects today and found a massive redistribution of snow since yesterday. Wind affect was widespread above 1300m and very pronounced above 1500m. Certain slopes were more skiable than others, but still had evidence of wind affect. Many slopes had a hard zipper-crust breakable wind slab on the surface ranging from 0.5-3" thick. We encountered reactive wind slabs up to 30cm in isolated areas that released on a single tap in a hand pit.

We skied some moderately steep terrain but tip toed around through obvious larger wind slabs. There was evidence of wind deposition of snow (since yesterday) as low as 1000m, and in open alpine terrain, the amount of snow on top of the crust ranged from 10cm-60cm.

Busy day up there, hopefully everyone stayed safe!