Yuma County, Arizona

A prolonged late-season heat wave has pushed Arizona toward its deadliest summer on record, with new data showing sharp increases in heat-related deaths across both urban and rural areas. In Maricopa County, home to Phoenix, officials confirmed 150 heat-related deaths so far this year, with 629 more under investigation. In Yuma County, 26 heat-related deaths have been recorded, already surpassing the 19 deaths reported for all of 2025, as extreme heat warnings remain in effect after Labor Day.

Emergency responders are strained by the ongoing crisis: Yuma firefighters responded to 78 heat-related calls this year, including 11 requiring intensive cooling therapy. Officials warn that outdoor workers, the elderly, and unsheltered residents face the greatest risk, often not realizing they are in medical danger until it's too late. Yuma County is keeping roughly 20 cooling stations open past their planned September closure if high temperatures persist into October.