Tenki Diary

Hakuba weather and snowpack data for the 24 hours to 7am Jan 17: very light snow (S-1) all yesterday. Another 3cm has falledn at 860m asl.  At 1600m asl at 1500hr yesterday there was 27cm of new snow.  This will have increased since that time.  I took a resort lift to 1600m to dig some snow pits. Nick from Hakuba Powder Lodging  had called me in the morning to ask about faceting of old snow given the colder than normal temperatures.

Faceting (more so, the temperature gradient) is particularly accelerated at crusts of ice. Facets at the crust are also quite problematic from a stability perspective. We have two crusts in or snow pack. On is a thick laminated rain and wind crust from 11 Jan. It is now under about 30cm of new very dry snow. The other crust is from the rain event on Dec 29. It has consistently been buried at about 140-190cm, depending on aspect and altitude. At 1590m I found it down at 130-150. Both crusts are laminated and both have evidence of faceting. It is not casing the remotest instability issue now, but it may later in time.

Besides the very loose and dry HN24 on top of the ice, the snowpack is almost literally rock solid. Even the mid-pack rounds are pen-plus in hardness.

FYI, I broke my avalanche shovel digging this pit. Here is the profile.