Japan hits 40°C for the first time under a new heat warning

On July 21, 2026, Japan saw its first "kokushobi" — a new top-level heat warning the weather agency created in April 2026 for days that reach 40°C (104°F) or hotter. Three cities, including Toyota and Gujo, hit or passed that mark, setting records. The agency made the category because such extreme days now happen often enough to need their own label. Dangerous heat was expected to last past July 22.