An avalanche in a dream symbolizes a loss of emotional control.
The snow in an avalanche represents repressed (numbed) emotions. If you dream of an avalanche, it may be sign that you have repressed your emotions so much that they are in danger of overwhelming you.
An avalanche dream may be a warning that you need to express yourself more. You need to make your feelings more apparent to yourself and to others.
The avalanche in your dream may also represent another person who you feel is controlling you or dominating you, especially someone who tends to have emotional outbursts.
If you dream that you are rescued from an avalanche, your dreaming mind is sending you a message that you have the power to overcome great obstacles.