You're above tree line and about to drop onto a nice face when suddenly the weather moves in and all depth perception is lost. You can't tell the difference between sky and snow - up from down, left from right. It's tough to know if you're even moving. And then you remember that cliff. Now where was it?
Experienced ski mountaineers are ready for this scenario; most keep a roll of fluorescent orange tape (the bio-degradable kind, available at a local hardware store) in their packs. If they've really thought ahead, they'll even have a bundle of small sticks or wands to tie the tape to and stick in the snow to mark a safe route.
But while wanding the terrain will help the people skiing behind you, it doesn't do much for you as you stare into the milk. To find your way through a whiteout, tie a section of the orange tape around a rock or snowball leaving a long tail behind it, and throw the missile several feet down the hill. Follow the neon, making slow, cautious turns with a widened stance until you reach your rock . Pick it up and toss it again. Repeat the process - unless the tape drops over a cliff - until you're out of the soup.
Ski mountaineer Hilaree O'Neill works as a heli-ski guide in Alaska's Chugach Range and has bagged first descents in Mongolia, Russia, and India.