A powerful storm in southern Yukon Thursday knocked out power in a few communities and started at least one new forest fire.

Yukon Energy said the thunderstorm damaged its main power line carrying electricity from the Aishihik Dam. As many as eight towers on the main power line were damaged or knocked down.

That knocked the power out in Champagne and Mendenhall.

Yukon Energy Operations Manager Guy Morgan said power was re-routed from the Whitehorse dam to feed Champagne and a back-up diesel generator was started up to power Mendenhall.

Morgan believes one of the cross members on the main power line coming out of the Aishihik Dam failed and the weight of the line and the wind caused a domino effect causing other towers to fail. He said crews and replacement parts are on their way but repairs are going to take some time.

 "Haven't had something like this in quite a few years so it will be a couple of days here yet," he said.

Crews are still checking for damage on smaller powerlines in the area.

Fire at Mount Lorne

In Mount Lorne, a lightning strike started a forest fire at Cowley Lake Thursday afternoon.

Residents Bob and Clara Sharp were first to notice it and called in the alarm.

"We saw the lightning strike hit beyond our property," said Bob Sharpe.

"There was smoke and in 30 seconds we noticed flames above the tree line and I called 911, then Wildland Fire, then the Mount Lorne hamlet council fire department."

Sharpe said within about 10 minutes a helicopter was overhead and the Mount Lorne volunteer crews had responded.