Phoenix's record summer heat killed over 600 people, new report says
Phoenix's summer proved the deadliest on record. Over 50% more people died of heat-related illnesses than during the previous record year, officials said.
Historic heat wave sets several all-time records in Phoenix
File: Phoenix became the first major city to average 100 degrees for an entire month.
PHOENIX – The record number of heat-related deaths in Phoenix's Maricopa County for 2023 trounced the previous record by more than 50%. This is the seventh consecutive record-setting year.
The county's Department of Public Health concluded that heat killed 645 people in 2023 compared to the 425 heat-related deaths in 2022.
HOW TO TELL THE DIFFERENCE BETWEEN HEAT EXHAUSTION AND HEATSTROKE
The number of heat related deaths per year in Maricopa County from 2013 to 2023.
(Maricopa County Department of Public Health / FOX Weather)
HEAT KILLS MORE AMERICANS THAN FLOODING, TORNADOES, HURRICANES OR LIGHTNING
Heat deaths include "heat caused" deaths where environmental heat was directly involved in the sequence of events causing deaths. The number also includes "heat contributed" deaths where the environmental heat contributed to the death but was not in the sequence of events causing the death. Of the deaths, 59% were caused by heat.
More than half the number of deaths occurred in July. On average, 13 people died per day that month, 10% higher than any previous year.
July was the hottest month ever on record for Phoenix, with an average temperature (low and high averaged together) of 102.5 degrees. It was the first major U.S. city to ever average over 100 degrees for a month. The normal average for July is 95.5 degrees, according to NOAA.
EVEN CACTI IN DESERT SOUTHWEST ARE HAVING A TOUGH TIME IN HISTORIC HEAT
A sign reading 'Today's High: 115' is posted in South Mountain Park amid the city's worst heat wave on record on July 25, 2023 in Phoenix, Arizona.
(Mario Tama / Getty Images)
From the last day of June to the last day of July, the mercury hit 110 degrees or higher every day. That destroyed the previous record stretch from 1974 of 18 consecutive days at the Phoenix Sky Harbor Airport. On three days, the city hit 119 degrees for a high.
The NWS issued an Excessive Heat Warning every day from July 1-29 and a total of 42 days for the entire year.
DOCTORS SEE MORE HEAT-RELATED ILLNESSES IN OUTDOOR WORKERS AS HEAT WAVE DRAGS ON
A billboard displays a temperature of 118 degrees Fahrenheit (48 degrees Celcius) during a record heat wave in Phoenix, Arizona on July 18, 2023.
(Patrick T. Fallon / AFP / Getty Images)
Officials also released some other statistics about the heat-related deaths in the Phoenix area.
- 71% of the deaths occurred on a day the NWS issued an Excessive Heat Warning. Over the past five years only 32% of deaths occurred when that warning was in place.
- More than three out of every four victims were male.
- About 67% of outdoor deaths occurred in an urban area. About 6% of those happened at a bus stop. Only 26 deaths occurred in cars.
- One out of every 2 victims had a history of physical and/or medical conditions.
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Image 1 of 4Indoor versus outdoor deaths. (Maricopa County Department of Public Health)
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Image 2 of 4Indoor versus outdoor deaths. (Maricopa County Department of Public Health)
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Image 3 of 4Since 2013 a greater share of the deaths were unhoused. (Maricopa County Department of Public Health)
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Image 4 of 4Types of physical conditions of those that suffered heat-related deaths. (Maricopa County Department of Public Health)
"This tragic number shows us how much work we still have to do," said Dr. Rebecca Sunenshine, medical director for MCDPH, in a statement. "With a coordinated county-wide strategy, nearly every one of these deaths can be prevented."
Phoenix was not the only city to suffer a heatwave. The year 2023 is now in the record books as the warmest year recorded in the world's history. Scientists warn that 2024 already has a 99% chance of being among the five hottest years on record.