The Greenwood Fire barreled through northern Minnesota forests like a “freight train” Monday, doubling in size and burning so fiercely it created its own weather. “Once it starts rolling,” incident commander Brian Pisareck told reporters Monday night, “it starts to build up steam and feed off itself.” The intense heat from the fire, which had burned nearly 20,000 acres as of Tuesday evening, created pyrocumulus clouds (a.k.a. “fire clouds”) towering an estimated 10,000 to 12,000 feet into the atmosphere.

Severe and exceptional drought conditions across Minnesota, the Northern Plains, and Western U.S., made worse by climate change, have set the stage for the massive conflagration, one of 13 within Superior National Forest, including four new fires on Monday alone. Those fires, and specifically the John Elk and Whelp Fires have forced the closure and evacuation of the Boundary Waters Canoe Area Wilderness. (Greenwood Fire: New York Times $, Star Tribune, Duluth News Tribune, MPR, KSTP5, KBJR6, KMSP9, KARE11; Drought: New York Times $; BWCAW: Duluth News Tribune, Star Tribune, E&E $, Duluth News Tribune, AP, MPR; Climate Signals background: Drought, Wildfires)