The very first case of snow immersion in the Midwest happened right here in the U.P at Mount Bohemia.

LAC LA BELLE -- Snow immersion is a serious type of skiing accident that kills about a dozen people in the U.S. every year. It's when a skier falls into an area of deep, soft snow and becomes immobilized. It is rare, but it does happen. Just ask David Marsek of Milwaukee. Friday afternoon, he had the scare of his life.

"I was just going around a tree," explains Marsek. "The nose of my snowboard got stuck in the snow, and the next thing I knew, I flung forward. I just went straight in like I was diving into a pool of water, but I was diving into a pool of snow."

Luckily, Marsek had one hand free and was able to move the snow away from his mouth so he could breath--until his friend arrived to help.

"Well, he's a trickster and a jokester," says Marsek's friend Rob Summervell. "So at first, I didn't take him seriously. I just saw these two legs sticking out of the snow waving around."

But summervell quickly realized this was no joke.

"So I just started digging around his head," recalls Summervell. "I got it cleared out around his head right away. It was something to dig him out."

A few minutes later, the ski patrol was on the scene.

"The hill employees were right on it," says patrol director Patty Asselin. "They went right there and dug around him and pulled him out by the shoulders."

They had him out in less than 10 minutes. Anything longer, and Marsek would have run the risk of suffocation.

Ski patrol staff say the recent warmer temperatures are causing the snow to soften. And parts of the hill are reaching 4 feet in depth. This means the chance for sinking is high.

Experts say snow immersion is preventable. Avoid skiing around the base of trees and ungroomed trails, and always ski with a partner.