IB Path

The intention of this tour was to determine the accuracy of this mornings forecast and examine slopes for storm slab and wind slab instability, as well as gather general conditions information and examine the snowpack for PWLs.

Wx conditions were variable with shifting strong winds from the west to the north.  Winds along the Agassiz ridge were nearing 50 mph.  Leeward zones were calm until winds shifted to the north.  Overall a cold day with lots of wind transported snow.

Summary:  The big discovery of the day was that the ice lens is not covered by sufficient snowfall in IB path, Snow Survey and portions of Snowslide.  Wind drifts below the ridgeline showed some signs of instability with shearing and some shooting cracks, but no propogation occured on ski cuts.  Wind slabs along core ridge were reactive.  Two small D1 wind slabs were intentionally triggered on ski cuts on core ridge.  Larger slabs of D1.5 -D2 in size were intentionally avoided.  Slopes in both Snowslide and the Humphrey Cirque were highly wind affected, but not reactive.  

Test Results:  An ECT was dug at the top of IB path.  Results were 1F to P hard windslab 80 cms in depth.  Results were ECTX.

In general, shallow wind affected turns were available in specific locations, but accessing these turns and egress from the east side remains challenging.  Conditions are highly variable and snow surfaces are difficult to read. 

A near miss occured today when I took a fall on difficult to read conditions on the ice lens in the Inner Basin path.  Fortunately, I was able to arrest.  I lost a ski that traveled approximately 400 vertifical ft.  Glad I had crampons available to walk down and recovery the ski, and ski crampons to traverse the ice layer out of the bottom of the IB path.  Continue to ski cautiously and watch for thin cover above the ice sheet.

On the way out from Humphrey's cirque winds were picking up and starting to turn the surface layer of northern hardcore ridge north facing shoots to windboard.  Hopefully, these winds subside and leave some soft snow.

On a final note two naturally triggered wind slab avalanches were observed.  One in IB path and one in Snowslide.  These were both D2 in size and likely occured on the evening of or early morning of 2/19.  They were highly eroded but debrief piles were observed at trees and the bottom of the path.