Avalanche Forecast
Purcells
Tune in to patterns of wind redistribution to help you navigate around newly formed wind slabs. Surface clues won't help with more dangerous deep weak layers, so seek out simple terrain that is free of overhead hazard.
Avalanche Problem 1: Wind Slabs
What Elevation?
Which Slopes?
Chances of Avalanches?
Expected Size?
Travel and Terrain Advice
- If triggered, wind slabs may step down to deeper layers and result in very large avalanches.
- Seek out sheltered terrain where new snow hasn't been wind-affected.
- Use ridges or ribs to avoid pockets of wind loaded snow.
Avalanche Problem 2: Persistent Slabs
What Elevation?
Which Slopes?
Chances of Avalanches?
Expected Size?
Several deeply buried weak layers continue to produce very large avalanches on a regular basis. This is happening both naturally and with large triggers. This is a time to carefully limit your exposure to avalanche terrain and avoid overhead hazards.
Travel and Terrain Advice
- Either avoid or space out and travel quickly through runout zones of avalanche paths.
- Seek out low angle, low consequence terrain as well as terrain that has seen heavy traffic.
- Solar radiation may act as a natural trigger for very large avalanches on Monday.
Avalanche Summary
Reports from Saturday showed new storm slabs and wind slabs releasing from size 1-2. These occurred naturally as well as with remote (from a distance) triggering and explosives control. Crown depths ranged from 15-60 cm, owing to snow redistribution from recent strong winds.
Friday's reports included observations of a size 2 persistent slab that was remotely triggered on a northeast aspect at 1900 metres in the north of the region, failing on the mid-January weak layer down 70 cm. Another report details a size 3.5 persistent slab that released naturally in the past couple of days in the north of the region. This avalanche initiated at 1400 metres and ran to the bottom of its path, producing a 3 metre high deposit of debris.
On Thursday, explosive control work produced slab avalanches up to size 3 on a variety of aspects between 1900 m and 2500 m.
Reports from Wednesday included observations of explosives control in the Bugaboos and surrounding area producing numerous persistent slab results from size 2-3.5. Many of these avalanches ran on the mid-December layer buried 150-200 cm deep. Northwest through northeast aspects in the alpine were the primary targets.
Snowpack Summary
Recent storms have produced variable new snow accumulations of 20-50 cm. This snow overlies a complex and generally weak snowpack structure with three active weak layers that we are monitoring:
70-120 cm of snow overlies a crust and/or surface hoar layer (from mid-January). The crust is reportedly widespread, except for possibly at high elevations on north aspects. The surface hoar is 10-30 mm in size and exists at all elevation bands.
Deeper in the snowpack (down about 80-130 cm), a persistent weak layer known as the early-January layer is present at all elevation bands, and composed of surface hoar on sheltered slopes and sun crust on steep solar aspects. Recent snowpack tests have shown sudden fracture characters with moderate loads and high propagation potential.
Another persistent weak layer that was buried mid-December is 90 to 200 cm deep and consists of a facet/surface hoar/crust combination. It is most problematic at and below tree line and features prominently in recent avalanche reports.
Weather Forecast
Monday: Mainly cloudy with isolated flurries and a trace of new snow. Light west winds. Alpine high temperatures around -11 in the north of the region and closer to -7 in the south.
Tuesday: A mix of sun and cloud. Light northwest winds. Alpine high temperatures around -12 in the north of the region and closer to - 8 in the south.
Wednesday: Cloudy with light flurries bringing a trace to 3 cm of new snow over the day. Snowfall increasing overnight. Moderate west winds. Freezing level rising to a possible 1500 metres with alpine temperatures around -4.
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.
New snow and steady southwest winds have been building touchy wind slabs in lee terrain. Be especially cautious around slopes that see sunshine on Monday. Slabs are likely to exist on all aspects in areas that received more snow from recent storms.