1. Avalanches Current Weather Avalanche Triangle Avalanche Types Slides
For Next Class: Read Chapter 18

2. Avalanche Triangle

3. WEATHER
Snow Storm
Wind

4. WEATHER DANGERS
Big Snow Storm
30+ cm
Wind
20+ kph

5. TERRAIN DANGERS Slope Angle Terrain Traps Convex Slopes Cornices
30 to 45 degrees
Terrain Traps
Convex Slopes
Cornices

6. 38 degrees
Slope angles
From Staying Alive In Avalanche Terrain p. 63, Bruce Tremper after Schweizer& Jamieson

7. Valleys/Canyons
Moraines
Crevasses
Terrain Traps

9. CONVEX SLOPES

10. Cornice Formation

11. Cornice Falls Most commonly release due to daytime warming
Less commonly from overburden of drifting snow
Other factors include:
Weakening on windward side (solar warming, wind-erosion)

12. SNOWPACK DANGERS
Shooting Cracks
Collapsing Snow
Recent Avalanches

13. T. Murphy

14. Slab Avalanches Strong snow over weak snow Fractures in rapid sequence
Releases as a unit
Can be small or large and highly destructive

15. SLOPE ANGLE >30 degrees
SLAB Dense snow layer
Weak Layer
Trigger you or me

16. ROUTE FINDING
Peter Thurston Photo

17. Route-Finding
Avoiding the hazard ?
Snow Japan

18. This must include everyone in your group!!
REQUIRED Avalanche Rescue Equipment When Traveling in Avalanche Terrain…
Photo of ski touring
This must include everyone in your group!!

19. Required Avalanche Rescue Gear
A working AVALANCHE BEACON
Metal SHOVEL
Collapsible PROBES
(digital -triple antenna)

20. KEY POINT:
Avalanche rescue skills & equipment – Is NOT a justification for choosing high consequence terrain when avalanche hazard and uncertainty exist.

21. Take Home Point To Remember
New Snow
30+ cm Storm
Best to Wait 1-2 days

22. Avalanche Awareness

23. Tunnel Creek