Note: this bulletin is published in the pm and effective for the following day. Be alert to differences in the forecast and actual snowfall amounts and weather activity overnight.
Backcountry Avalanche Danger Rating
Upper (>1000m): LOW
Mid (800-1000m): LOW
Lower (<800m): LOW
Current Avalanche Problems
Storm Slab | Likelihood: Possible | Size: small-medium
Wind Slab | Likelihood: Unlikely | Size: small-medium
Glide Slab | Likelihood: Unlikely | Size: medium-large
Forecast models are indicating that our next wave of snowfall should be kicking into action tomorrow afternoon/evening. Assuming we wake up to little or no fresh snowfall, the danger level will be at LOW for most of the day. Hazard levels will be increasing as the flakes start to hit the ground, so be alert to significant new snow accumulation (ie, > 6” or 20cm). Many slopes have been either wind polished or sun baked leaving them firm and unlikely to bond as well as usual to a fresh coat of storm snow.
Expect hazard levels to increase rapidly to either MODERATE or even CONSIDERABLE as the next storm cycle sets in. Aside from slide potential within the storm snow layer, keep in mind that new snowfall will stress and place a new load on existing snowpack structures. If there are wind slabs, or even more likely, glide slabs primed to slide, this storm could set off some large natural avalanches. Unless you are extremely confident in your terrain assessment skills, I recommend sticking to the trusty old rules of thumb and giving the storm snow 24-48 hours to settle out before venturing into backcountry terrain. This includes side country terrain access out of resort gates. There is no distinction!
I don’t expect too much new snow until later tomorrow, however, be alert to a surprise early dump.
Please familiarize yourself with the danger rating scale. You can find some great information on it here
As a local guide and avalanche professional, I have chosen to share this hazard assessment in the interest of encouraging better information sharing within the local community. This avalanche bulletin is to be used at your own risk and is based on very limited data gathered by myself and other guides working for Japan Powder Connection. Please use this information in addition to other resources and take responsibility for your own actions in the backcountry. Also, please respect and abide by all Niseko Area Rules. This information applies only to backcountry areas accessed externally from area resorts. This information is published the evening before and in effect for the following day.
As always, remember that making good decisions in the backcountry takes years of practice and experience. Having the gear is a small part of the equation. Take an avalanche safety course and hire a properly trained guide so you don’t learn the hard way!
Japan Powder Connection - Professional Backcountry Guides and Instructors
Niseko Avalanche Information - Niseko’s avalanche information page. Not a ‘bulletin’ by Western standards, but Shinyasan has been doing this for 20+ years and knows these mountains far better than myself.
Snow-Forecast - Niseko Area Weather Forecast
Niseko Now - Local Weather and Conditions Summary