Know the weather = know the snow pack = know the stability.  For previous weather and snow reports use the Diary link at the top of the page.

I haven't had the chance to update the weather diary in a few days.  And it has been a dramatic few days as well.  Since Friday-Saturday last week we have plunged horribly fast into late spring conditions, with no gradual transition.  Constant winter storms followed by instant warm weather.  I don't like it at all.  The anticipated clear weather was welcome, but not to this extreme.

Steep Deep Japan Hakuba  weather data for the 24 hours to 7am for 860m. Max temp +13C, min temp -3C and  +3C at 7am. 0cm of new snow  in the last 24 hours.  Depth of snow 170cm after settlement.  Barometer 9121mbar.  The sky is has 100% cloud cover (fog), not snowing, no wind. 

Field observations:  Yesterday we travelled in the backcountry to 2200m and observed south, east and northerly aspects in the Tsugaike-Otari area.  North aspects had fair stability even in the middle afternoon.  Any other aspects that has sunshine were unstable and releasing single pint and skier triggered slow wet sluffs and slides.  Previous evidence of solar triggered slides down long gullies and cornice fall triggers.  Below about 2000m avoid solar aspects after lunch on any day, all together on sunny days and generally only in the morning before they have thawed (assuming there was a sub zero night).

At altitude (above 2200m) we observed intense snow transport to the extent that we witnessed wind triggered slab avalanches.  We decided not to continue any higher.  Wind loading from the west through SW is significant and today we cancelled a trip to the alpine on a  loaded aspect.

The snowpack had rain to 1300m on Monday.