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
Current Avalanche Problems
Storm Slab | Likelihood: Likely | Size: small - medium
Wind Slab | Likelihood: Likely | Size: small - medium
No field observations today, but we woke up to another ~20cms of snow in the valley. While yesterday’s storm layer should be stabilizing, today’s snowfall has added an additional load to the snowpack and may or may not result in a thicker and stronger slab. You’ll need to assess that for yourself wherever you end up. Also worth noting is that yesterday’s storm had some significant graupel and rimed particles accumulating in the top few cms, which will make an nice sliding surface for today’s storm layer. Be alert out there. I’m keeping the danger rating at MODERATE for tomorrow, but it’s on the upper reaches of that rating and pretty close to CONSIDERABLE. Additionally, temps are forecasted to rise above freezing tomorrow afternoon. This could have critical effects on surface slabs and we will likely see some melt-freeze conditions in the afternoon and into Monday. Be extra cautious traveling beneath corniced ridges tomorrow as the temps warm!
Cornices are growing rapidly, but still manageable. Cornices are starting to overhang and release easily. Yesterday we observed one small, natural release directly below a corniced ridge (1 - NTL - S - N - SS - R1.0 - D1.0).
Be on the lookout for sudden changes in ski pen on cross loaded and leeward slopes, especially near ridges with visible cornice development. My main concern is going to be these wind slabs on isolated features.
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 all area resorts. This information is normally published the evening before and in effect for the following day.
As always, remember that making good decisions in the backcountry takes a lot 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 - Shinyasan’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