[SS]

Avalanche Bulletin - Banff, Yoho and Kootenay National Parks

Issued Sat Apr 19, 2014 17:00
Valid Until Sun Apr 20, 2014 17:00
Hazard is subject to rapid change based on the duration and intensity of the sun over the day. Start early, get up high for the best skiing and get back early. DK

        

Danger Ratings: Sunday

alpine treeline below treeline alpine: 2 - Moderate, treeline: 1 - Low, below treeline: 2 - Moderate
alpine: 2 - Moderate
2 - Moderate Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
  • 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.
More...
treeline: 1 - Low
1 - Low Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
  • 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.
More...
below treeline: 2 - Moderate
2 - Moderate Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
  • 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.
More...
Forecast Monday Tuesday
alpine
2 - Moderate 2 - Moderate
treeline 2 - Moderate 2 - Moderate
below treeline 2 - Moderate 3 - Considerable
Confidence: Good

Weather Observations

Past 24 Hr WeatherN Kootenay 1985/2405mBow Summit 2000mSunshine 2200m
Maximum (°C)-3-23
Minimum (°C)-7-710
Snowfall (cm)Not AvailableNot AvailableNot Available
Snow Pack (cm)242167190
Wind speedLight (1-25 km/h)Light (1-25 km/h)Light (1-25 km/h)
Ridgetop wind directionSWSW
Past 24 Hr WeatherN Kootenay 1985/2405mBow Summit 2000mSunshine 2200m
Maximum (°C)-3-23
Minimum (°C)-7-710
Snowfall (cm)Not AvailableNot AvailableNot Available
Snow Pack (cm)242167190
Wind speedLight (1-25 km/h)Light (1-25 km/h)Light (1-25 km/h)
Ridgetop wind directionSWSW
Low Moderate Considerable High Extreme
  • 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.
  • 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.
  • 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.
  • 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.
  • Avoid all avalanche terrain.
  • Natural and human-triggered avalanches certain.
  • Large to very large avalanches in many areas.

Problem 1: Loose Wet

Which Elevation?

Which Elevation? below treeline, treeline

Which Slopes?

Which Slopes? west, southwest, south, southeast

Chance of Avalanches?

Chance of Avalanches? possible

Expected Size?

Expected Size? small - large
Subject to the duration and intensity of the sun. Areas near and around rocks will break down quick and steeper areas have real potential to move and build volume quickly.

Travel and Terrain Advice

  • Start and finish early before the surface crusts melt.

Problem 2: Cornices

Which Elevation?

Which Elevation? alpine, treeline

Which Slopes?

Which Slopes? east, southeast, southwest, south, west

Chance of Avalanches?

Chance of Avalanches? possible

Expected Size?

Expected Size? small - large
Cornices appear to be more sensitive to temperature fluctuations. They are just so unpredictable that it would be prudent to give them a wide berth.

Travel and Terrain Advice

  • Cornices become weak with daytime heating, so travel early on exposed slopes.
  • Give cornices a wide berth when travelling on or below ridges.

Problem 3: Deep Persistent Slabs

Which Elevation?

Which Elevation? alpine

Which Slopes?

Which Slopes? south, southeast, east, northeast, north, northwest, west, southwest

Chance of Avalanches?

Chance of Avalanches? unlikely - possible

Expected Size?

Expected Size? small - large
This layer is just so unpredictable. Super stubborn, but terrible consequences if you trigger it; most likely from a shallow rocky location.

Travel and Terrain Advice

  • Be aware of the potential for full depth avalanches due to deeply buried weak layers.