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Snowstorms and Avalanches

What is snow? Soil particles that have been dressed up in ice Crystals that have formed around tiny bits of dirt that have been carried up into the atmosphere by the wind Causes If the air in a cloud is below freezing, water vapor turns to ice instead of rain. Ice crystals stick to one another to form snowflakes If the air temperature is 32 degrees or below, it will snow. Effects Blizzards Avalanches Damage to people and property Dangerous traveling Loss of electricity Isolation

Types of Snowflakes

Types of Avalanches

• Dust Avalanche- the snow is not tightly packed, instead the snow is loose, fluffy and powdery
• Slab Avalanche- a mass of snow or ice breaks loose and slides down the slope
• Snow Avalanche- snow that has not been packed starts to crack and falls down the slope

States with Avalanche Fatalities

Safety Tips in an Avalanches

• Cup your arm or hand in front of your face to create an air pocket
• If you are buried do not panic, relax and try to save your oxygen
• If you are near the surface, try to dig yourself out slowly
• If you are not sure how covered you are, wait for a rescue team
• If you are not under the snow, climb up to a high spot
• Bring an avalanche beacon with you if you are going into the mountains

Danger Level and Color	Natural Probability	Human Triggers	Degree of Avalanche Danger	Recommended Action
Low (green)	Very unlikely	Unlikely	Generally stable snow with isolated areas of instability	Travel is generally safe. Normal caution advised.
Moderate (yellow)	Unlikely	Possible	Unstable slabs possible	Use caution in steep areas.
Considerable (orange)	Possible	Probable	Unstable slabs probable	Increased caution in steep areas.
High (red)	Likely	Likely	Unstable slabs likely	Travel not recommended.
Extreme (red with black border)	Certain	Certain	Extremely unstable slabs certain.	Travel not recommended and should be avoided.

Try this at home:

• Collect snow in a container and mark the level.
• Measure how much water forms when the snow melts.
• There should be less water than snow.