- Date
- Thursday, January 7, 2016
Cold dry weather continues ...
Avalanche Problem Summary
The most likely avalanche problem for this upcoming weekend is:
Wind Slabs: Where the wind blows dry snow into fresh pillows. This is most likely behind ridge crests, but also to the lee of ribs. Terrain features act like snow fences allowing drifts to build on one side, typically slopes facing northly and easterly
Travel advice
- Watch for wind loaded pockets of snow on the downwind side of ridges and use caution as you transition into wind affected terrain at treeline and alpine elevations.
- Ease into big terrain by first testing rolls and small features – looking for shooting cracks and trying to trigger baby slides – before riding smaller representative slopes (similar elevation, aspect, and steepness). This allows you to gain information and assess conditions before committing to bigger objectives.
- As always, ride slopes one at a time, have a buddy watching you from a safe spot, and set up so it’s easy to turn toward the exit (in other words toward safe terrain).
- If you’re riding slopes from the bottom up, trigger points are more likely near the top of the slope (close to the ridge) than mid- or lower-slope.
Kakwa Weather Information
The remote weather station at Babette Lake, just west of Kakwa Lake is a great new source of mountain weather information for an important riding area in the region. Check it out: www.avalanche.ca/kakwa. A big shoutout to Swan City Snowmobile Club for their support!
This week the Kakwa data shows it warmed to just touching zero on January 1 and 2, before falling to the -15 C range. The snow surface temperatures stayed cold, which suggests only South facing aspects formed a melt-freeze crust and it’s still dry and loose on shady slopes. Even though there hasn’t been any new snow, the snow depth remains around 150 cm. The data shows the snow surface temperature is much colder than the air temperature measuggesting to me that shady slopes have dry loose “facetted” snow. I’m guessing “sugary powder” for the top 30cm or so.
Snowpack Summary
From the limited information available, the snowpack looks relatively good, meaning softer & powdery snow near the surface with the snow increasing in hardness (and strength) with depth. There are reports, primarily from Pine Pass, that below the most recent storm snow there’s a layer of feathery surface hoar, but until the next storm I don’t think this layer is deep enough to pose much hazard.
Weather for the Weekend
The BC weather story remains the same: big cold arctic High is sitting over us, it’s blocking storms and sending them north to Alaska or south to California. Through the weekend it’s almost certain to be dry, very likely to remain cold, and quite possible to have a good amount of sun in the mountains. BC’s best mountain weather forecast is updated every morning at avalanche.ca/weather
Effect of the Weather on the Snowpack
Cold temperatures, little wind, and no new snow mean avalanche conditions are unlikely to change significantly. Additionally, last week’s warm temperatures helped settle and consolidate the snowpack at least now that it’s cooled off (In the longer term, after it cools off, the snow emerges stronger; in the short term heat weakens snow).
Low Hazard doesn’t mean NO Hazard. Normal caution is still required for windslabs. It is possible that strong sunshine starts some snowballing and small loose wet slides on steep solar slopes. Finally, there is also the more remote (but higher consequence) chance of a slab avalanche occurring in a lower weak layer.
The North Rockies is a data sparse region and therefore it’s hard to provide a “high confidence” assessment. That means assessing conditions for yourself is an important skill for managing your individual risk. You can both get local reports and share your observations on Avalanche Canada’s Mountain Information Network – it only takes a few minutes and you DO NOT need to be an Avi Guru. Finally, because none of us has perfect risk management skills, having rescue gear and knowing how to use it remains a necessary condition for riding in avalanche terrain.