When you're hurtling high through the air on an upside down snowmobile, the difference between glory and ruin comes down to a few miles per hour.

Minnesota native and Winter X Games gold medalist Levi LaVallee hit that sweet spot Saturday afternoon when he launched himself over Nicollet Mall for his signature back-flip jump and stuck the landing — a thrilling punctuation mark at the UpsideDowntown event hosted by Polaris.

A snow-dusted crowd counted down the moment to LaVallee's leap and yelped in surprise when he soared into the air. For a few surreal seconds, the athlete floated from one ramp to the other, his Vikings apparel visible even from the ground.

"Can you imagine being his mom?" Jenny Semenkewitz asked.

Semenkewitz, who was visiting from Florida, watched a replay of the stunt on a nearby screen moments after the real jump ended.

"It was nerve-racking," she said.

The supersized jump left plenty of room for nerves for LaVallee. The daredevil has done plenty of back flips before, sure. But they're typically performed with only 70 feet between ramps. On Saturday, the distance stretched about 100 feet.

That means a bigger ramp, a bigger landing and bigger consequences if something had gone wrong.

"It's something I'm confident in but at the same time, the bigger the jump gets, the more you have to be focused and the more you have to do it spot on," LaVallee, 35, said Friday.

Minutes before the event began, there was nary room to take a selfie as bundled up onlookers packed around the ramp area, jostling for a better look. "It's like the state fair cookie line!" one man yelled.

Frank Heaney, a 20-year-old Minneapolis native, craned his neck over bulky winter hats and kids perching on parents' shoulders as a series of opening stunts began.

"I think they did a good job Minnesota-fying everything," Heaney said, gazing around Nicollet Mall. "If it's going to be cold, it might as well be snowing."

Cathy Burriss, of Minnetrista, agreed about the large, sloppy snowflakes.

"It kind of drives it all home," Burriss said. "We're a hardy bunch."

Hannah Covington • 612-673-4751