Arizona recorded 977 heat-related deaths in 2024, with Maricopa County accounting for about 63% of the fatalities, according to the Arizona Department of Health Services. Officials said the state’s extreme heat, which lasts from May to September, continues to drive one of the highest heat-related death rates in the nation despite recent declines.
The county’s heat-related fatalities numbered 430 in 2025, marking a second consecutive year of decline from 645 deaths reported in 2023, according to the county’s annual report and NPR. Despite the decrease, Maricopa County experienced a heat-related death every day from June 13 to September 5, 2025, officials said.
Maricopa County, home to the Phoenix metropolitan area, accounted for about 63% of Arizona’s 977 heat-related deaths in 2024, according to the Arizona Department of Health Services (ADHS).
Most heat-related deaths in Maricopa County occurred outdoors, with 74% of fatalities in 2025 happening outside, according to county data. The timing of deaths shifted slightly, with 37% occurring in August, compared with previous years when July accounted for the majority. The ADHS 2024 report indicated that over 45% of Arizona’s heat-related deaths happened in July. Furthermore, 42% of the 2025 deaths took place during periods when excessive heat warnings were in effect, while about half occurred on days with moderate heat risk, the county reported.
Substance use and homelessness were significant factors in the heat-related fatalities. Maricopa County reported that 236 deaths, or 55% of heat-related fatalities in 2025, involved substance use, with stimulants implicated in 82% of those cases. The Guardian reported that individuals experiencing homelessness represented 40% of the county’s heat-related deaths that year, and substance misuse was linked to two-thirds of the fatalities. A University of Arizona white paper highlighted that rising deaths are associated not only with temperature increases but also with social factors such as homelessness, drug use patterns, housing costs, and social isolation.
Statewide, ADHS data show that more than 4,320 people died from exposure to excessive heat in Arizona from 2013 through 2024. The University of Arizona white paper noted that the state’s heat-related death rate has increased roughly tenfold over the past two decades and now far exceeds rates in other hot states, including Texas. The paper estimated that warming temperatures since 2001 contributed to approximately a 40% increase in heat-related deaths in Maricopa County, translating to roughly 40% more deaths in 2023 than would have occurred without the temperature rise. The analysis indicated that each one-degree increase in daily median temperature corresponds to a 15% to 20% increase in heat-related deaths.
The demographic profile of heat-related deaths in Arizona shows that 65% of fatalities in 2024 were among people aged 50 or older, and males accounted for three out of every four deaths, ADHS reported. Half of the heat-related deaths involved substance use, and over 55% of decedents had lived in Arizona for more than 20 years.
In addition to fatalities, heat-related illnesses place a substantial burden on emergency services. ADHS reported that approximately 4,298 people visit Arizona emergency rooms annually due to heat-related illnesses. Between 2012 and 2022, there were 1,879 deaths statewide attributed to exposure to heat from weather conditions.
The state’s extreme heat season, which lasts from May to September, remains a significant public health concern. ADHS described Arizona as “one of the hottest places on earth” during this period, underscoring the ongoing challenges posed by rising temperatures and associated social vulnerabilities.
Comments are closed.