Recent storm snow has been reactive on steep slopes. The presence of buried weak layers increases the potential size of avalanches.
Avalanche Problem 1: Storm Slabs




- The new snow may require several days to settle and stabilize.
- If triggered the storm slabs may step down to deeper layers resulting in large avalanches.
- Stay off recent wind loaded areas until the slope has had a chance to stabilize.
Avalanche Problem 2: Persistent Slabs




Several troublesome layers exist in the snowpack and may be reactive to large triggers such as a cornice or storm slab release. Human triggering may also be possible in shallow or thin, rocky areas.
- Pay attention to overhead hazards like cornices which could easily trigger persistent slabs.
- Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.
- Avoid steep convexities or areas with a thin or variable snowpack.
Avalanche Summary
On Wednesday, several avalanches were reported in recent storm snow up to size 2.5. Previously, a very large, widespread natural avalanche cycle up to size 4 was observed last week. Slopes of all aspects and elevations ran full path and reached valley floor. In some cases, mature timber was destroyed. Many of these failed on persistent weak layers mentioned in the snowpack discussion. Although natural avalanche activity on these layers has tapered-off, human triggering of very large avalanches remains a very real possibility.
Snowpack Summary
25cm of recent storm snow is settling into a slab in the upper snowpack. Wind data has been sparse, although I suspect strong winds have shifted these accumulations into deeper, reactive slabs in wind-exposed terrain. These accumulations overlie a mix of older wind slabs in exposed higher elevation terrain, a sun crust on steep solar aspects and surface hoar on sheltered slopes.
Below the snow surface, several persistent weak layers make up a troublesome snowpack. In the top 1-1.5 m of the snowpack, two surface hoar layers buried in January can be found. Expect to find at least one of these layers on all aspects and elevations.
Deeper in the snowpack (120-200 cm deep) is a facet/crust/surface hoar layer from December, most prevalent at and below treeline.
Near the base of the snowpack is a crust/facet combo, most likely to be triggered from thin spots in the alpine.
All of these layers have produced large avalanches recently. The wide distribution and ongoing reactivity of these layers suggests that avoidance through choosing simple terrain is the best strategy.
Weather Forecast
Friday: 5-10 cm new snow. Treeline temperature around -7C. Westerly ridgetop winds gusting to 50 km/h.
Saturday: 2-5 cm new snow. Treeline temperature around -12C. Light variable winds.
Sunday: Sunny but cold. Treeline temperatures around -17C. Winds light northeasterly.
Avalanche Forecasts in your Inbox
Avalanche Canada has switched to an RSS feed for its daily forecasts. This is a much more flexible method that allows automatic delivery to your email inbox, or to an RSS reader of your choice.
What are RSS feeds?
RSS (Really Simple Syndication) is a popular standardized file format allowing up-to-date delivery of web-based content. RSS feeds enable you to receive content updates from websites, delivered to your email through an RSS aggregator (such as blogtrottr.com) or viewed through applications called RSS readers (such as feedly.com).
Set up an RSS feed for your email:
Select a RSS aggregator
- Cariboos URL:
http://www.avalanche.ca/api/forecasts/cariboos.rss - Copy the url and paste it into the appropriate field of your RSS aggregator.
- Fill in your email address.
- Voila! Watch the Avalanche Canada forecast roll into your inbox.
Forecast Disclaimer
Avalanche Canada's Public Avalanche Bulletin, and other information and services provided by Avalanche Canada, are intended for personal and recreational purposes only.
**THIS INFORMATION IS PROVIDED "AS IS" AND IN NO EVENT SHALL THE PROVIDERS BE LIABLE FOR ANY DAMAGES, INCLUDING, WITHOUT LIMITATION, DAMAGES RESULTING FROM DISCOMFORT, INJURY, OR DEATH, CLAIMS BY THIRD PARTIES OR FOR OTHER SIMILAR COSTS, OR ANY SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, ARISING OUT OF THE USE OF THE INFORMATION.**
The user acknowledges that it is impossible to accurately predict natural events such as avalanches in every instance, and uses the data in this bulletin with this always foremost in mind. The accuracy or reliability of the data is not guaranteed or warranted in any way and the Providers disclaim liability of any kind whatsoever, including, without limitation, liability for quality, performance, merchantability and fitness for a particular purpose arising out of the use, or inability to use the data.
New storm slabs may be especially reactive in wind-exposed terrain, and may be slow to gain strength due to a mix of underlying weak surfaces. Watch for new wind slab development and reverse loading due to northwest winds on Thursday.