After searching for more than 48 hours, rescuers finally found the US teen, who went missing while skiing off-piste Sunday near the Alpine resort in western Switzerland, police in the canton of Vaud said in a statement.
"The man was found conscious, in a state of hypothermia and exhaustion, and stuck waist-deep in the thick blanket of snow," police said, describing his survival as "miraculous".
He had told his rescuers that he had left the prepared slopes to "freeride" back to the resort.
But on his way down the mountain, he got lost and broke one of his bindings.
He tried to continue on one ski, but fell into a stream.
Exhausted and soaked, the 19-year-old was then caught in a storm, which snowed him under and trapped him for the next two days.
"The skier was relatively well-equipped when it came to clothing, but had no working means of communication and none of the vital material needed when skiing off-piste," such as a shovel or sensor, police said.
The skier, whose life was not in danger, was taken by helicopter to the Zweisimmen hospital near Bern.
The American's rescue came after 12 off-piste skiers were killed in avalanches in the Swiss Alps over a period of five days, following heavy snowfall.