Predicament: You're crossing a snowy backcountry bowl when you hear it: the telltale whumph of a slide just starting to happen.
Lifeline: Yell to alert your group, then run or ski out of the avalanche's path. If there's no escaping, drop your pack, crouch behind a tree or rock, and turn away from the slide. If the snow sweeps you away, mimic swimming strokes to stay near or above the surface. When the slide begins to slow, move aggressively: Stand up (so you're closer to the surface); put your arms in front of your face, elbows out (to create an air pocket); take a huge breath and hold it (to give your chest room, once the snow sets); and, at the last second, thrust an arm toward the surface (to help rescuers find you). You'll have only about 3 seconds to carve out space before the snow settles. If it settles loosely and you have some mobility, dig upward. Don't know which way is up? Spit, then observe where gravity pulls your saliva. To avoid depleting your limited air supply, stay calm and yell only when rescuers are close.