Drought, abnormally hot temperatures last month as well as forecasts of hot and dry conditions in June mean the “table has been set” for significant wildfire activity this summer, an official from the British Columbia Wildfire Service.
Matt MacDonald, fire weather forecaster, said he and his colleagues are waiting to see if the month will bring the desperately needed rain.
“The classic saying, which we hear every year, is that the intensity of the fire season depends greatly on the amount of rain received in June,” he said.
Now that they are announced, the June forecast does not bode well.
MacDonald said the service looked at the amount of rain needed to alleviate persistent dry conditions and reduce the risk of wildfires. They found that it would take two to three millimeters of rain a day for 10 to 20 days in a row.
“I can almost guarantee that won’t happen,” he said.
A day or two of heavy rain here and there probably won’t reduce the risk, Matt MacDonald said, explaining that it’s more likely that runoff rain will replenish moisture in soils, which lose their ability to absorb water after a prolonged dry spell.
The Donnie Creek wildfire, which is currently burning over more than 1,700 square kilometers north of Fort St. John, is a perfect example, the weather forecasting official pointed out.
The fire received about 40 millimeters of rain on May 22 and 23, about 10 days after it was discovered, which slowed its activity for about a day, he said.
But within three days it was burning at an intensity of class five on a scale of one to six, with a “crown fire”, igniting and destroying entire trees.
Forty or 50 millimeters of rain sounds like a lot, “but given the underlying dry conditions, it’s just a drop in a very empty bucket,” MacDonald said.
British Columbia experienced a relatively dry January with snow accumulations well below normal levels, before catching up in March and April as temperatures remained relatively cool.
Then “May came like a lion,” MacDonald said, referring to the record-breaking heat wave that helped spark early-season wildfires in the province’s northeast.
Matt Loney, an Environment Canada meteorologist, said it was the first or second warmest May on record for at least 15 stations in British Columbia.
As late spring arrives and temperatures are once again warmer than normal in the forecast, Mr MacDonald said he expects to see the grass dry out, turn yellow and become ready to ignite by the third or fourth week of June.
“We’re going to start turning the corner, and these deeper and more persistent drought conditions are going to start showing their consequences,” he said.
The story of the 2023 wildfire season actually began last fall, he said.
Abnormally hot and dry conditions last October meant an extension of summer activities for many people in British Columbia, but also “increased the pace of the drought,” he said.
The province then headed for an early winter freeze. When spring 2023 arrived “we discovered even deeper drought conditions” in many areas, MacDonald said.
“It concerns a lot of us, to be honest,” he said. I think we are lining up for what could be a very active fire season. »
MacDonald said there are different types of drought, and they don’t always happen at the same time.
This year is “one of the few times when all droughts, no matter how you define them, whether it’s rivers, soil moisture, fuels, forests, all very clearly indicate high drought” in some parts of the province, he said.
Currently, these areas extend from the Cariboo region west of the Fraser River, approximately from the Municipality of 100 Mile House in Prince George, to the Smithers region and the Peace region on the east, where BC’s largest fires are currently burning.
The suspected causes of the fires are currently split 50-50 between humans and lightning this year in British Columbia, MacDonald said.
While people tend to imagine that a cigarette tossed out of a car window is the spark of human-caused forest fires, that’s not so common anymore, the specialist said. Ignition can be from a train, a chainsaw, a campfire that has not been fully extinguished, or people driving gasoline-powered vehicles through brush.
“If you ride a dirt bike, ATV or SUV, you may not have a spark arrester on your muffler, on your tailpipe,” MacDonald said. We really try to encourage people to be extremely careful. »