THE CANADIAN PRESS -- OTTAWA - The freak windstorm that toppled the main stage at the Ottawa Bluesfest may be a sign of weather to come, warns a top climatologist.

Provincial investigators combed the gnarled wreckage at the grounds of the festival on Monday for clues to explain how a violent summer gale destroyed the stage during a Cheap Trick concert the night before.

But one of Canada's foremost weather experts has his own theory: climate change.

Environment Canada senior climatologist Dave Phillips said it's not the days that are getting hotter -- it's the nights.

According to Phillips, there are more and more nights when the mercury stays above 20 Celsius. That means there is less time for the air to cool down at night, causing a build-up of hot air. When a cold front comes in, like it did on Sunday night in the Ottawa region, it's the perfect storm fuel.

"You do get the element of severe weather under something like this, when it's so hot and humid," Phillips said.

A century ago, Toronto would get three or four nights a year above 20 C. Now it's more like 20 nights a year, he explained.
"It's the fuel that drives storms."

He said Canadians can expect more of the extreme weather that howled through the concert grounds, sending thousands of people scurrying for cover as scaffolding buckled into a heap.

The storm also killed two people in boating accidents in west Quebec.

"This is really just a dress rehearsal of what we will see more likely in the future," Phillips said.

At least three concert-goers were hurt -- including the band's truck driver -- but the head of the festival says all have now been released from hospital.

Concertgoer Pamela Cogan, a respiratory therapist, was at the foot of the stage and jumped the barricades after the collapse to see if anyone required assistance. She said it was a "miracle" that nobody died.

"It was like a scene out of 'Armageddon.' Right before the collapse, it was sunny and lovely, and then moments later, dark clouds appeared, and the atmosphere changed. A gust of wind blew confetti from the ground up, the drapes blew inwards, the stage collapsed, and someone yelled, 'Get off,'" Cogan said.

She said she was shocked when the only injured person she could find was the truck driver behind the stage.

"It's a miracle, even the way the stage fell back and not forward onto the people at the show. There were fans sitting on the stage right behind the rigging. I have no idea how everyone made it out alive," said the 47-year-old veteran Bluesfest attendee, who watched the show with her son and his friends.

Cheap Trick manager Dave Frey, who was on stage seconds before the collapse, told Rolling Stone magazine that the driver's leg was broken and the band lost all of its equipment.

The veteran rock band -- best known for hits including "Surrender" and "I Want You to Want Me" -- said they were merely shaken, not hurt.

"Everyone is okay and we are so lucky to be alive and hope that all the fans are OK too," the band said in a message posted on their Facebook page.

Video of the Bluesfest site posted on YouTube showed the stage, which stood several storeys tall, being propelled backward before crumpling and damaging a tractor-trailer truck parked behind it.

A team from Ontario's Ministry of Labour was on site Monday looking for anything that might explain how the stage came tumbling down. The ministry will produce a report on the incident.

There are still more questions than answers. Namely, should organizers have called off the show when the weather turned nasty?

The executive director of Bluesfest says that's what they did.

"We were monitoring the weather and what was a watch turned into a more severe situation," Mark Monahan said at a morning news conference.

"And when that happened we called it immediately."

Environment Canada issued a severe thunderstorm warning about an hour before the stage collapsed. But Monahan said the festival can't stop every time the weather deteriorates.

"We deal with weather every day and we don't automatically call a show because we have weather we see coming in, because if we did that we wouldn't be able to run a festival."

He said the Sunday storm came in fast and left fast.

"It was a very unusual situation," Monahan said. "The fact that it brought that stage down and nothing else came down in the park was just a freak situation."

Monahan said he's now looking at closer liaison with the weather office.

He added the stage was a rental from Montreal firm Groupe Berger and was inspected regularly during the festival. The festival has rented the stage for the last five years. The company didn't return a request for comment.

The storm caused power outages on both sides of the Ottawa River. Hydro Quebec says about 61,000 households were left without power, mostly in the Outaouais and Laurentides, which still had outages in some areas Monday.

Quebec provincial police say two men in their sixties drowned in the area in separate incidents on Sunday night.

A police spokeswoman said a 61-year-old man from Saint Colomban, Que., drowned in the Baskatong Reservoir after the pontoon boat he was on flipped over in strong winds.

In the other incident, a 68-year-old Ottawa man lost his life after his pedal boat turned over on Lac la Blanche, near Papineauville.
In the Ottawa region, police said they received more than 300 emergency calls in a two-hour period on Sunday.

Environment Canada's Phillips said it's nearly impossible to predict these kinds of storms.

"Very difficult to forecast. It's like a pot of pudding on a stove and trying to guess where the firs bubble is going to break," he said.
"There's a lot of dynamics in the air. And, boy, there's not many structures that can withstand those kinds of winds."

Bluesfest is one of North America's largest musical events. The festival first took place in 1994 and has since grown from a one-stage, three-day event to a multi-staged, 12-day music showcase featuring some of the best international talent.

Bluesfest issued a statement saying that "due to extreme weather conditions, we have regrettably had to shut down all stages for the night." A keenly anticipated show by indie rockers Death Cab For Cutie was among those cancelled.

A deadly storm shut down a country music festival in Camrose, Alta., in July 2009. Actor Kevin Costner and his band Modern West were just going on stage at the Big Valley Jamboree when the storm hit.

The stage collapsed killing one woman and injuring 75 people.

-- with files from The Associated Press

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