[AH]

Avalanche Bulletin - Jasper National Park

Issued Sat Apr 19, 2014 17:00
Valid Until Sun Apr 20, 2014 17:00
The avalanche hazard will rise on slopes with prolonged exposure to the sun.  Plan to travel early to take advantage of the crust and be off big slopes by mid-day.

        

Danger Ratings: Sunday

alpine treeline below treeline alpine: 1 - Low, treeline: 1 - Low, below treeline: 2 - Moderate
alpine: 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...
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 3 - Considerable
treeline 2 - Moderate 3 - Considerable
below treeline 2 - Moderate 3 - Considerable
Confidence: Fair - Timing or intensity of solar radiation is uncertain on Sunday

Weather Observations

Past 24 Hr WeatherMarmot Basin 0800Columbia Icefields area
Maximum (°C)34
Minimum (°C)-7-5
Snowfall (cm)0.10
Snow Pack (cm)136100
Wind speedLight (1-25 km/h)Light (1-25 km/h)
Ridgetop wind directionSESW
Past 24 Hr WeatherMarmot Basin 0800Columbia Icefields area
Maximum (°C)34
Minimum (°C)-7-5
Snowfall (cm)0.10
Snow Pack (cm)136100
Wind speedLight (1-25 km/h)Light (1-25 km/h)
Ridgetop wind directionSESW
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? southeast, south, southwest, west

Chance of Avalanches?

Chance of Avalanches? possible

Expected Size?

Expected Size? small - large
Little overnight recovery of the melt freeze crust is expected.  Loose wet slides are possible by mid-day especially if exposed to intense solar radiation.

Travel and Terrain Advice

  • Start and finish early before the surface crusts melt.
  • Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

Problem 2: Deep Persistent Slabs

Which Elevation?

Which Elevation? alpine, treeline

Which Slopes?

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

Chance of Avalanches?

Chance of Avalanches? unlikely - possible

Expected Size?

Expected Size? small - large
No recent activity on this layer however triggering may be possible from thin rocky areas on loaded features.

Travel and Terrain Advice

  • Be aware of thin areas that may propogate to deeper instabilites.
  • Avoid convexities or areas with a thin or variable snowpack.