Top American skier Lindsey Vonn, the standout face of the 2010 Winter Games, sent tremors through the Olympic world on Wednesday with news that injury might stop the women's downhill favourite from competing.

While Vonn dropped the bomb two days before Games open in Vancouver, organisers finally got good news on the weather front as flakes fell on Cypress Mountain, the freestyle skiing and snowboard venue notorious these days for its lack of snow.

Snow also dusted the high-mountain slopes of Whistler, home to the Alpine events, but came with thick fog that aborted the first day of training for the men's downhill and raised the spectre of race postponement.

No amount of snow or nasty weather, however, could take the spotlight off the leading lady of what pundits have coined the "Vonn-couver" Games.

"Now I'm questioning whether I'll be able to ski," the fresh-faced Minnesotan told a news conference on Wednesday ahead of the 25-year-old's attempt for her first Olympic medal.

Vonn sustained a shin injury while in training in Austria last week and said it "was the most painful injury I have ever had," although she has not yet taken any pain medication.

Despite her scepticism, team doctors said Vonn should be able to train as scheduled on Thursday and they will make a final decision early in the day.

"I think she is heading in the right direction to be 100 percent ready for Sunday's super combined," said Bill Sterett, U.S. ski team doctor.

VONN'S COMPETITIVE DRIVE

The American is a gold medal contender in five events and arrives in Canada in a class of her own, with wins in eight of the 11 World Cup super-Gs and downhills so far this season.

Her absence could run deep in these Games, robbing broadcasters, sponsors and spectators of golden moments from a bone fide golden girl.

"Lindsey Vonn was going to be one of the great stars of these Olympics and probably the standout American heading into these Games," said Robert Boland, professor of sports management at New York University.

Some in the ski world wondered, however, if it was all just a bit of pre-Olympic drama that would evaporate as soon as the February 12-28 Games start.

"Knowing her, her competitive drive, if anybody can be ready to go when the gun goes off, it will be Lindsey Vonn," said Bill Marolt, president and chief executive of the U.S. Ski and Snowboard Association.

As the worries around Vonn surfaced, others eased.

The biggest headache for organisers thus far subsided somewhat as welcome snow arrived at a key venue craving a fresh dumping of the white stuff.

A record warm January in Vancouver forced organisers to mount a massive snow lift to Cypress this week and threatened to dampen the spectacle in this weekend's inaugural races.

"We have had a nice little dumping that's covering the trees. We expect more of this in the next couple of days. We are very happy," said venue spokesman Stephen Bourdeau.

POSSIBLE DOWNHILL DELAY

Fog and snow up on Whistler made organisers call off the first men's downhill training session after 42 of the 87 skiers had completed the course.

Skiers worried that weather might thwart training on Thursday and Friday also, which would lead to a postponement in Saturday's race since all competitors must complete one training run.

Some 5,000 athletes and officials will descend on Whistler and Vancouver for the Games, which will kick off on Friday with the first indoor opening ceremony ever in the 86-year history of Winter Olympics.

Under the traditional blanket of secrecy conferred to opening ceremonies, speculation swirls around the Canadian city who will light the Olympic flame and whether it will burn inside the stadium.

Buzz was building about a second cauldron that will burn on the Vancouver waterfront, a few minutes' run away from the opening ceremony.