Avalanche Forecast
Purcells
Tricky conditions warrant a conservative approach. A little warming, precipitation and/or wind-loading could be all we need to awaken a volatile persistent slab, especially at treeline.
Avalanche Problem 1: Persistent Slabs
What Elevation?
Which Slopes?
Chances of Avalanches?
Expected Size?
Travel and Terrain Advice
- Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Approach steep open or sparsely treed slopes cautiously.
Avalanche Problem 2: Loose Wet
What Elevation?
Which Slopes?
Chances of Avalanches?
Expected Size?
Loose snow avalanches may fail with human or solar triggers at alpine elevations.
Travel and Terrain Advice
- Use conservative route selection. Choose moderate angled, well supported terrain.
- Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.
Avalanche Summary
Little avalanche activity was reported in the last two days, but whumpfing and cracking was observed in the north of the region on Tuesday between 1700 and 2100 m. Last weekend, a size 1.5 avalanche involving two people near Invermere was reported. It was suspected to have run on the mid-December weak layer. On Saturday a skier triggered a size 2 persistent slab avalanche running on a layer of facetted snow from mid-December. This happened in the north of the region's Dogtooth Range on a west aspect at 2400m. Expect the potential to trigger persistent slabs to increase as last week's storm snow continues to settle into a cohesive slab.
Snowpack Summary
Warming is starting to turn dry powder into a cohesive slab in some areas. The main troublemaker in the snowpack at the moment is a layer of feathery surface hoar down 40-70 cm, buried in mid-December. In places this interface exists as a crust/facet combo. It is most prevalent around treeline, but has been reported as high as 2400 m. A little more warming, precipitation and/or wind-loading could be all that is needed to turn powder into an easy-to-trigger slab above this touchy interface. It's tricky to predict and even professionals are scratching their heads a bit about exactly when and where this beast will wake up. It’s a good time for conservative decision-making.
Deeper in the snowpack (about 70-110 cm down), a rain crust from November remains in the back of our minds, but it is considered dormant for now. If you have any recent observations, please share them through the Mountain Information Network.
Weather Forecast
Thursday: Clear in the alpine, with valley cloud. A layer of warm air is expected between about 2000-2500 m, while valleys remain cold. Light variable winds. Increasing cloudiness in the evening, with flurries possible overnight.
Friday: Cloudy with flurries. Light southwesterly winds.
Saturday: Light snow (~5 cm). Light westerly winds.
More details can be found in the Mountain Weather Forecast.
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
- Purcells URL:
http://www.avalanche.ca/api/forecasts/purcells.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.
A weak layer of surface hoar buried 30-50 cm deep is expected to become more reactive as warmer temperatures help settle recent new snow into a cohesive slab.