[SH]

Avalanche Bulletin - Banff, Yoho and Kootenay National Parks

Issued Thu Apr 17, 2014 17:00
Valid Until Fri Apr 18, 2014 17:00
Fresh snow has reset the ski conditions and overall we have a stable snowpack. When you plan your trip, remember that the basal weak layers are still present in thinner areas, and that we are not in full spring mode as of yet. SH

        

Danger Ratings: Friday

alpine treeline below treeline alpine: 2 - Moderate, treeline: 1 - Low, below treeline: 1 - Low
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: 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...
Forecast Saturday Sunday
alpine
2 - Moderate 2 - Moderate
treeline 1 - Low 1 - Low
below treeline 1 - Low 1 - Low
Confidence: Fair - Freezing levels are uncertain on Thursday

Weather Observations

Past 24 Hr WeatherN Kootenay 1985/2405mBow Summit 2000mSunshine 2200m
Maximum (°C)Not AvailableNot AvailableNot Available
Minimum (°C)Not AvailableNot AvailableNot Available
Snowfall (cm)Not AvailableNot AvailableNot Available
Snow Pack (cm)Not AvailableNot AvailableNot Available
Wind speedNot AvailableNot AvailableNot Available
Ridgetop wind directionNot AvailableNot AvailableNot Available
Past 24 Hr WeatherN Kootenay 1985/2405mBow Summit 2000mSunshine 2200m
Maximum (°C)Not AvailableNot AvailableNot Available
Minimum (°C)Not AvailableNot AvailableNot Available
Snowfall (cm)Not AvailableNot AvailableNot Available
Snow Pack (cm)Not AvailableNot AvailableNot Available
Wind speedNot AvailableNot AvailableNot Available
Ridgetop wind directionNot AvailableNot AvailableNot Available
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: 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
The basal layer is still a prominent feature of the snowpack in thin and variable areas. It is being well bridged and is unlikely to be triggered, but the consequences could be large if you hit the right spot.

Travel and Terrain Advice

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

Problem 2: Loose Dry

Which Elevation?

Which Elevation? alpine

Which Slopes?

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

Chance of Avalanches?

Chance of Avalanches? possible

Expected Size?

Expected Size? small - small
With more snow and some wind in the forecast, watch out for power sloughing on steep slopes and gullies (40 deg +) as well as small pockets of wind slab near ridge crests.

Travel and Terrain Advice

  • Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.

Problem 3: Loose Wet

Which Elevation?

Which Elevation? alpine, treeline, below treeline

Which Slopes?

Which Slopes? west, southwest, south, southeast

Chance of Avalanches?

Chance of Avalanches? possible

Expected Size?

Expected Size? small - large
Although the forecast is mainly cloudy for Friday, any period of sun will be intense enough to affect the new snow.

Travel and Terrain Advice

  • Start and finish early before the surface crusts melt.