Data Class | Information category | Observations Made | Red Flag Values | Your Observations |
Weather |
Precipitation | Type | Rain/heavy wet snow | |
Intensity | >3 cm / hr | |||
Accumulation | >30 cm/ 12 hr | |||
Wind | Speed | Strong enough to move snow | ||
Direction | Moving snow onto/across route | |||
Duration | Long | |||
Temperature | Current | ≥ 0◦c | ||
Maximum | ≥ 0◦c | |||
Minimum | ≥ 0◦c | |||
Trends | Rapid change | |||
Solar radiation | Cloud cover | Allowing a lot/ intensifying | ||
Intensity | Strong | |||
Duration | Long | |||
Snowpack |
Snow Cover | Height | < 1.5m | |
Strength | Weak | |||
Variability | High | |||
Layers | Strength | Strong over Weak | ||
Temperature | Near/= 0◦c | |||
Grain Characteristics | Large, loosely packed, angular grains | |||
Bonding | Strength | Compression test ≤20 Rutschblock ≤4 |
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Plane Characteristics | Smooth, Clean | |||
Failure Layer | Large, loosely packed, angular grains | |||
Whumping | Initiation | Natural/Human Trigger | ||
Propagation | Far (>3m) | |||
Extent | Widespread | |||
Avalanche Activity |
When | Current | Observed | |
Recent | <24 hr (Maritime climate) lt;48 hr (Continental) |
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Past | If condition still exists | |||
Where | Area | Widespread | ||
Terrain Type | Similar to route | |||
Terrain Traps Angle/Aspect | Traps exist where avalanches are running | |||
What | Natural Triggers | All Natural Triggers | ||
Human Triggers | All Human Triggers | |||
How | Destructive Potential | ≥ Class 2 | ||
Propagation | Wide fracture lines running far | |||
Failure Layer | Large, loosely packed, angular grains |