Extreme lightning sparks more Alaska wildfires in already historic season

An unusual spate of lightning has ignited more than 50 new wildfires in Alaska, worsening air quality, preparing communities to evacuate and exacerbating an already historic fire season in the state.

More than 2.4 million acres have burned across the Interior this year – among the most burned acres so early in the year in at least eight decades. As of Wednesday, more than 200 fires are actively burning across the state, straining firefighting resources.

Wildfire smoke has worsened air quality over the central and eastern Interior and the western Yukon Territory. On Tuesday, communities in Anderson, Clear and Clear Space Force Station were advised to prepare to a “go bag.” Predicted thunderstorms could bring lightning that could spark new wildfires.

The Alaska Interagency Coordination Center (AICC) issued a Preparedness Level 5, the highest level, for the seventh day in a row . The designation is assigned “when large fires that require incident management teams are occurring in several areas” and based on “burning conditions, the probability of new ignitions, the potential for extreme fire behavior, predicted weather, and resource availability.”

Hot, dry conditions are fueling this year’s unprecedented activity. Snowpack was unusually sparse in the state’s southwest this winter, followed by a dry and warm spring. A warming atmosphere, brought on by human-caused climate change, has also lengthened the growing season and increased the number of trees and plants, which act as fuel.

Then the lightning came, providing the necessary initial spark. An outbreak of thunderstorms in late May and early June brought lightning and ignited vegetation. Communities evacuated, and dense smoke plumes appeared over Fairbanks.

More than a million acres had burned by June 18, over a week earlier than any other season in the modern record.

This past weekend, another round of thunderstorms brought an exceptional siege of lightning – worsening fire conditions. An unusual weather pattern over the North Pacific pumped moisture into the heart of Alaska beginning on Friday, allowing daily rounds of thunderstorms to develop over the mountains of eastern portions of the state and northwest Canada’s Yukon Territory. As these storms crawled northwest through Alaska’s interior, thousands of lightning strikes lit up the region.

On Saturday, more than 7,180 lightning strikes hit Alaska and neighboring sections of Canada, per the Bureau of Land Management’s Alaska Fire Service. Another 10,500 lightning bolts struck the next day. The tally is among Alaska’s highest two-day lightning totals in the past decade.

Thunderstorms are not uncommon in the Alaskan summer, but this degree of storminess is unusual.

Rick Thoman, a climate expert who works with the University of Alaska’s International Arctic Research Center, acknowledges that historical counts of lightning strikes are hard to come by, but in his experience, “the amount of lightning over the weekend, with a two-day total of nearly 18,000 strikes in and near Alaska,” was exceptional; the type of barrage that “likely only happens once every few summers.”

Monday and Tuesday had seen an additional cumulative 10,195 strikes. Forecasters believe the active lightning will worsen the fire situation for the state, leading to numerous ignitions that could each grow into large wildfires.

Forecasters believe the unusually active lightning will worsen the fire situation for the state, leading to numerous ignitions that could each grow into large wildfires.

More than fifty wildfires have started since Sunday, and more will likely develop through the coming weekend as lightning continues and fires initially too small for detection expand.

The National Weather Service office in Fairbanks, Alaska has issued a Red Flag Warning for fire weather across much of the state’s interior. “Ample lightning,” the warning advises- as many as “5000 lightning strokes a day”- “could lead to numerous new fire starts” through Friday.

Wildfires are common in the 49th state. Sparked by lightning and human activity, they rip through the extremely flammable black spruce forests that dot Alaskan permafrost between May and August. The average wildfire season between 1950 and 2019 in the state saw around 975,000 acres burn, according to data from the AICC.

Some years see almost no wildfire activity, while others feature a combination of atmospheric conditions for wildfire development and spread, such as dry conditions, frequent lightning-producing thunderstorms and hot spells.

2022 is gearing to be one of the more active years. Only one other year – 2015 – has experienced more burned acres at this point in the season in the reliable record. Fires in 2015 continued to burn more than 5 million acres of Alaskan wildland.

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Kasha Patel contributed to this report.