Wildfires make own weather systems

A combination of intense heat and drought conditions is causing wildfires in Canada to generate their own weather systems, experts say.

Michael Fromm, a meteorologist with the U.S. Naval Research Laboratory, said the phenomenon is known as a pyrocumulonimbus firestorm and has been tracked this year in B.C., Saskatchewan, Alberta, Manitoba and Ontario.

Scientists have been tracking the storms since May. The first one was seen this season in Manitoba, Fromm said. The Village of Lytton in B.C. saw firestorms on two successive days in late June, he said.

“It was probably the single largest pyrocumulonimbus storm of the year so far,” Fromm added. “In fact, we're still tracking the smoke plume from that storm as it's travelling around the world and it's about to kind of come full circle back over U.S.A. and Canada.”

An abundance of fuel, heat and wind create perfect conditions for the firestorms.

Lytton hit a Canadian temperature record of 49.6 C the day before a wildfire erupted there, destroying much of the community.

“When you get all those three things together, you get the perfect triple that we call fire weather,” Fromm said. “So, hot, dry and windy.”

Simon Donner, a climate scientist from the University of British Columbia, said the storms also generate lightning that cause more fires.

“The fire creates the storm and then the storm creates lightning, which can cause more fires,” he said.

“That runaway feedback is the dangerous part.”

Above average temperatures for many parts of B.C. aren't expected to ease soon. Environment Canada said there's no hint of rain until at least the weekend for some southern regions that have been hit hard by wildfires.

Emergency Management BC said more than 250 active wildfires were burning in B.C. on Monday afternoon. Since the fire season began April 1, 4,142 square kilometres of land has been charred from the 1,216 wildfires that had started as of Sunday night.

Canadian Forces have been deployed to B.C. and Manitoba to fight the fires.

Four teams, each with 21 soldiers, were sent to four locations in Manitoba on the weekend. Another team of 21 is expected to arrive in northwestern Manitoba by the end of Tuesday, Lt.-col. Jesse van Eijk said Monday.

The soldiers are assisting crews from the province in monitoring wildfires in Sherridon, Nopiming, Gympsumville and Swan River.

“Most of them are actually camping along the fire lines overnight. During the day, they walk the fire line and check for any areas where there's flare ups or hot spots, and they suppress those,” said van Eijk.

The federal government previously committed to sending up to 120 members as the number of wildfires grows in Manitoba.

While van Eijk is familiar with this type of work because he helped with the Saskatchewan fires in 2015, he said it's rare for the army to help with wildfires in Manitoba.

“It's been an exceptional year, ” he said.

The Manitoba government said the number of fires so far this year is slightly above average.

“We have a total of 351 fires for this year, whereas our normal average is about 322,” said Don Hallett, assistant director of Manitoba Wildfire Service.

There are about 130 active wildfires in the province, with about two dozen considered out of control.

More than 2,500 members from five First Nations had to leave their communities last week due to smoke and wildfires.