Angle Mountain

Cleared the interval board:  13", 2.7" SWE (last cleared 2/11)  Total HS: 57"

Recent storm snow combined with wind during and shortly after the storm has created a dense slab. Ski pen was 5-10cm in most locations. Southerly tilts had a 1cm breakable crust from recent sun and warm temps. Settled powder surface conditions on shady aspects and widespread surface hoar up to 10,000 feet.

I dug two pits and got propagation in both. Both pits had buried surface hoar above the January drought facets. The surface hoar was not very well preserved at this point, but still present. There is also a hardness change of at least one step at both drought interfaces in these pits.

9400' northwest aspect: HS 69 inches. ECTP13 down about 20 inches on surface hoar capping the January drought facet layer.

10,050' north aspect: HS 91 inches. ECTP20 down 26 inches, also on surface hoar above the drought layer.

There is a stiffening slab on Togwotee Pass on top of weak snow from January and early February.  It might take a large trigger, such as a snowmobile or several people, to impact buried weak layers and trigger an avalanche. Or you might find a thin weak spot in the overlying slab and trigger an avalanche in steep rocky terrain. Either way, you might not see any signs of an avalanche before it's too late, and the resulting slide could be very large and destructive.

 

 

 

Two small localized collapses in sheltered NW facing terrain around 9,000'.