Avalanche Forecast

Kootenay Boundary

Date issued

Mar 19, 2018 - 4:13 PM

Valid until

Mar 20, 2018 - 2:00 PM

Prepared by

ghelgeson

It is a good time to be traveling in the mountains, but remember that low danger does not mean no danger. Loose wet avalanche activity should be limited Tuesday, but stubborn old wind slabs and large cornices demand our respect.

Regular season
Monday - March 19, 2018
Alpine

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Treeline

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Below Treeline

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Tuesday - March 20, 2018
Alpine

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Treeline

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Below Treeline

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Wednesday - March 21, 2018
Alpine

3 - Considerable

Dangerous avalanche conditions. Careful snowpack evaluation,cautious route-finding and conservative decision-making essential.

Natural avalanches possible;human-triggered avalanches likely.

Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas.

Treeline

2 - Moderate

Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

Natural avalanches unlikely; human-triggered avalanches possible.

Small avalanches in specific areas; or large avalanches in isolated areas.

Below Treeline

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Avalanche Problem 1: Wind Slabs

What Elevation?
Which Slopes?
Chances of Avalanches?
Expected Size?

It is a good time to be traveling in the mountains. Increased cloud cover should put the brakes on loose wet activity. Use normal caution and be aware that small wind slabs near ridge crest may be sensitive to human triggering.

Travel and Terrain Advice
  • Be careful with wind loaded pockets, especially near ridge crests and in extreme terrain.
  • Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.
  • Give cornices a wide berth when travelling on or below ridges.

Avalanche Summary

No significant avalanche activity to report from Saturday or Sunday.

Avalanche activity on Friday was limited to snowballing on solar aspects.

On Thursday small loose avalanches were reported on steep features as the new snow ran on a crust. A few small skier triggered wind slabs were also reported from east facing alpine terrain.

Snowpack Summary

A crust has formed on all solar aspects. Fresh surface hoar has begun to form on polar aspects (those that face north and east) near ridgetop.

About 5 cm of snow is between the surface and another interface that mirrors the surface; crust on solar, surface hoar on high elevation north.

Snow that fell March 8th/9th was redistributed by west/southwest wind, forming wind slabs at high elevations. These wind slabs rest on a layer of surface surface hoar about 25 to 40 cm below the surface which has not been recently reactive.

A mix of weak layers exist 50 to 100 cm below the surface, including small surface hoar on shady aspects and a crust on solar aspects. These layers are expected to have gained strength from recent cycles of warming and cooling. Like other deeper weak layers that formed in January and December, they are considered dormant at this time. These deeper layers include several surface hoar and facet layers 1 to 2 m below the surface and a crust/ facet interface near the base of the snowpack.

Weather Forecast

Tuesday offers a bit of a drying trend for most of the province. A low approaching from the Gulf of Alaska may bring some precipitation to the region beginning Wednesday afternoon.

TUESDAY: Broken cloud cover with a bit of clearing in the afternoon, freezing level beginning at 600 m rising to 1500 m, moderate southwest wind, trace of precipitation possible.

WEDNESDAY: Few clouds initially with scattered cloud cover building in the afternoon, freezing level beginning at 600 m rising to 1600 m, light to moderate southerly wind, trace of precipitation possible.

THURSDAY: Overcast, freezing level beginning around 1200 m rising to 1900 m, strong southerly wind, 8 to 15 mm of precipitation possible.

Danger Ratings Explained

1 - Low

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

2 - Moderate

Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

Natural avalanches unlikely; human-triggered avalanches possible.

Small avalanches in specific areas; or large avalanches in isolated areas.

3 - Considerable

Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

Natural avalanches possible; human-triggered avalanches likely.

Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas.

4 - High

Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.

Natural avalanches likely; human-triggered avalanches very likely.

Large avalanches in many areas; or very large avalanches in specific areas.

5 - Extreme

Avoid all avalanche terrain.

Natural and human-triggered avalanches certain.

Large to very large avalanches in many areas.

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

  1. Kootenay Boundary URL: http://www.avalanche.ca/api/forecasts/kootenay-boundary.rss
  2. Copy the url and paste it into the appropriate field of your RSS aggregator.
  3. Fill in your email address.
  4. 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.