The ferocious thunderstorm that rolled through southern and central Yukon Wednesday night brought thousands of lightning flashes.

"It was definitely an intense system,” Environment Canada meteorologist Doug Lundquist said this morning.

Lundquist said the storm was brewing for some time over Alaska before moving across the Yukon.

Within 50 kilometres of Whitehorse alone, there were 300 lightning flashes, Lundquist pointed out.

Yukon Wildland Fire Management is reporting a total of 5,000 flashes across the entire Yukon on Wednesday.

Aircraft are out today flying much of the territory to look for new fires as a result of the lightning activity, fire information officer George Maratos said this morning.

He said most of the lightning activity was accompanied by rain.

Firefighters are staffing three new lightning fires detected Wednesday in the Mayo district, two of which are estimated at under three hectares, the other estimated at one tenth of a hectare.

Another lightning fire detected yesterday in the Carmacks district is burning in the wilderness zone.

Quick action Wednesday by the Wildland Fire crew in Haines Junction along with the community's volunteer firefighters is being credited for containing a fire that started in the Pine Lake subdivision after a tree fell onto the power line.

The fire hazard across the territory is low to moderate, with the exception of the Dawson City district, where the risk remains high.

Lundquist said last night's storm was accompanied by varying amounts of rainfall.

At Environment Canada's station at the top of Two Mile Hill, for instance, there was 1.8 millimetres of rainfall recorded but a private station in Hidden Valley measured 11.7 mm, he pointed out.

The level of Marsh Lake rose by 1.6 centimetres – just over half an inch – from Wednesday morning to this morning, according to the federal lake monitoring station.

The lake level, however, remains at 25.4 cm, or 10 inches, below the flood stage. The Yukon government's weekly flood-risk report issued Wednesday says the threat of flooding in the Southern Lakes region remains low.

Lundquist said recent daytime heating in the Yukon and Alaska resulted in the buildup to last night's storm, which caused a power outage on one road in the MacPherson subdivision.

While more thunderstorms could occur in the next few days as the warm weather continues, it's not likely they would be as intense as last night's, he said.

"The ridge is rebuilding not that that system has moved off, so it will still remain warm for the next week,” said Lundquist.

"We are looking at 23 to 25 for the next week, and normal daytime high is 20.

"But August is a really cooling-down month for the Yukon.”

Lundquist said July was 1.4 degrees above average.