Lightning, which is more common in hotter temperatures, is usually the cause of wildfires that burn the most land. In 2023, scientists at Canada’s natural resources department found that lightning sparked fires that burned 93 percent of the total wildfire area, and the remaining seven percent of the area burned from human causes.

Authorities in Manitoba, which shares a border with the U.S., issued a state of emergency. Winds will likely blow wildfire smoke into Midwestern states.