I spent 8 days back-country skiing in the Hakuba Region Dec 27 - Jan 3. We found that in spite of the extremely low snow conditions - we were able to find good to great skiing on all days. On all days but one, we used the lifts to access back-country ski areas above the piste and then used the lifts to download.
Ski resorts in the Hakuba region have more developed policies for accessing / leaving the back-country than in Hokkaido. Similarly - each ski area has its own method for accessing the back-country and strategy. Skiing the trees off piste in bounds is not allowed in most resorts and you can lose your pass. Be sure to familiarize yourself with the rules of each resort. I briefly include what I learned from the 3 ski areas we visited.
The best conditions report of all the regional resorts comes from the Happo-one snow report. There is a Japanese Avalanche bulletin - but it was not yet operational and is in Japanese.
This is one of the most versatile ski hills in the region for back-country skiing and my go to choice for stormy weather days when freezing levels and snow conditions demand that you go into upper elevations.
It is also a great choice when you want to access some bigger alpine lines without skiing to valley bottom
From the top of the ski hill most folks access the regions tree runs and upper blows via a cat road at 1600m.
Note: The S slopes above this road until the first switch-back MUST be avoided as part of a permanent closure where they threaten the Cat Road - in other words - the zone from the skin-up spot to the first switchback are permanently closed.
Happo-One Ski area.
This resort provides access to big alpine lines and long runs to valley bottom - when conditions allow.
There are also some lovley more conservative bowls to be skied near ridgetop - a short hike from the top of the lifts.
This resort tolerates folks leaving the resort at the top of the lifts to access the Happo-one ridge.
Skiing big lines to valley bottoms demands good hazard assessment, conservative terrain use and sufficient snow to the roads. Keep in mind that the gondola and upper lifts are prone to shut down in moderate winds leaving you waiting in horrific lines or having to "skin" up past closed upper lifts to access the good skiing.
Cortina / Norikura Ski areas.
This is one of the few resorts in the region that allows off piste tree skiing in bounds. Given the low snow conditions - we were only able to ski here one day. There are gates to leave the resort into the back-country.