Four wildfires broke out on the North Slope within 17 minutes Thursday

Alaska 511 recorded four wildfires within 17 minutes of each other Thursday afternoon on the North Slope, spread across roughly 40 miles at their widest in the Brooks Range foothills. The Heather, Etivluk, Ivotuk and Imiaknikpak fires were all logged between 3:01 and 3:18 p.m., and all four are under fire investigation. The records show when each was discovered, not when it started, and don't yet list a size.

The cluster stands out in a quiet fire year. About 43,000 acres had burned statewide through July, the third-lowest total since 1993, and tundra fires have been rarer still: only 286 acres of Alaska tundra had burned through July 24, the lowest since 1998, according to climate specialist Rick Thoman.

Four ignitions in 17 minutes across 40 miles of tundra is the kind of pattern a single lightning system produces. And it's the kind of event expected to grow more common in this part of Alaska. The Brooks Range foothills sit in a tundra ecoregion projected to face rising wildfire risk as the climate warms, through hotter summers, more lightning and drier ground. What caused these four remains undetermined.