Excessive Heat and Heat in Arizona, August 15 to 17, 2023

Name: Excessive Heat and Heat in Arizona, August 15 to 17, 2023
Start: 2023-08-15T00:00
End: 2023-08-17T20:00
Location: Arizona

August 15 to 17, 2023 · NWS PSR · 24 events in 21 counties and zones

Where it happened

Every event with a place to put it; 24 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 21
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 24

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS PSR wrote it up.

An upper level ridge of high pressure strengthened over the Intermountain West going into the latter part of August, leading to excessive heat conditions across south-central Arizona. Afternoon high temperatures observed at Phoenix Sky Harbor climbed between 111-115 degrees during the August 15-17th timeframe. On the 16th, the high temperature of 115 degrees tied the record high for the date set back in 2020. According to the Maricopa County Department of Public Health, there were 20 heat-associated fatalities that occurred during this event. Additionally, one heat-associated fatality occurred in La Paz County during this time.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Phoenix, AZ wrote its last area forecast discussion before the first event at Aug 14, 10:43 PM MST, 1 hour 17 minutes earlier.

Area forecast discussion, Aug 14, 10:43 PM MST, 1 hour 17 minutes before

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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

20 excessive heat, 4 heat. Local standard time, as filed.

Heat, Central Phoenix

When: August 15, 12:00 AM MST to 11:59 PM MST
Where: Central Phoenix forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

One direct fatality was reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Heat, North Phoenix/Glendale

When: August 15, 12:00 AM MST to 11:59 PM MST
Where: North Phoenix/Glendale forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

One direct fatality was reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Heat, East Valley

When: August 15, 12:00 AM MST to 11:59 PM MST
Where: East Valley forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

One direct fatality was reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Heat, Central la Paz

When: August 16, 12:00 AM MST to 11:59 PM MST
Where: Central la Paz forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 33.729, -113.981 (the zone’s center; the record gives no point)

One direct fatality was reported in La Paz County, with their details, such as age, gender, circumstances, and exact location unavailable.

Excessive Heat, Central Phoenix

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Central Phoenix forecast zone
Deaths: 8 direct, 3 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Eleven heat-associated fatalities (8 direct and 3 indirect) were reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Excessive Heat, Scottsdale/Paradise Valley

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Scottsdale/Paradise Valley forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

One direct fatality was reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Excessive Heat, North Phoenix/Glendale

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: North Phoenix/Glendale forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

One direct fatality was reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Excessive Heat, East Valley

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: East Valley forecast zone
Deaths: 3 direct, 0 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Three direct fatalities were reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Excessive Heat, Buckeye/Avondale

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Buckeye/Avondale forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

One direct fatality was reported by the Maricopa County Department of Public Health, with their details, such as age, gender, circumstances, and exact location unavailable.

Excessive Heat, Aguila Valley

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Aguila Valley forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Northwest Valley

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Northwest Valley forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Tonopah Desert

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Tonopah Desert forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Gila Bend

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Gila Bend forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Cave Creek/New River

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Cave Creek/New River forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Deer Valley

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Deer Valley forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Fountain Hills/East Mesa

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Fountain Hills/East Mesa forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, South Mountain/Ahwatukee

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: South Mountain/Ahwatukee forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Southeast Valley/Queen Creek

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Southeast Valley/Queen Creek forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Northwest Pinal County

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Northwest Pinal County forecast zone
Reported by: County Official
Coordinates: 32.904, -111.345 (the zone’s center; the record gives no point)

Excessive Heat, West Pinal County

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: West Pinal County forecast zone
Reported by: County Official
Coordinates: 32.904, -111.345 (the zone’s center; the record gives no point)

Excessive Heat, Apache Junction/Gold Canyon

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Apache Junction/Gold Canyon forecast zone
Reported by: County Official
Coordinates: 32.904, -111.345 (the zone’s center; the record gives no point)

Excessive Heat, Sonoran Desert Natl Monument

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Sonoran Desert Natl Monument forecast zone
Reported by: County Official
Coordinates: 33.349, -112.491 (the zone’s center; the record gives no point)

Excessive Heat, Parker Valley

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Parker Valley forecast zone
Reported by: County Official
Coordinates: 33.729, -113.981 (the zone’s center; the record gives no point)

Excessive Heat, Yuma

When: August 16, 10:00 AM MST to August 17, 8:00 PM MST
Where: Yuma forecast zone
Reported by: County Official
Coordinates: 32.769, -113.906 (the zone’s center; the record gives no point)

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

Event	Date	Where	Kind
Heat, Central Phoenix	2023-08-15	Unknown	Direct
Heat, North Phoenix/Glendale	2023-08-15	Unknown	Direct
Heat, East Valley	2023-08-15	Unknown	Direct
Heat, Central la Paz	2023-08-16	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-18	Unknown	Indirect
Excessive Heat, Central Phoenix	2023-08-17	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-16	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-16	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-16	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-17	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-17	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-18	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-18	Unknown	Direct
Excessive Heat, Central Phoenix	2023-08-18	Unknown	Indirect
Excessive Heat, Central Phoenix	2023-08-18	Unknown	Indirect
Excessive Heat, Scottsdale/Paradise Valley	2023-08-16	Unknown	Direct
Excessive Heat, North Phoenix/Glendale	2023-08-17	Unknown	Direct
Excessive Heat, East Valley	2023-08-16	Unknown	Direct
Excessive Heat, East Valley	2023-08-17	Unknown	Direct
Excessive Heat, East Valley	2023-08-17	Unknown	Direct
Excessive Heat, Buckeye/Avondale	2023-08-17	Unknown	Direct

What these are

Heat: Heat below excessive heat criteria that still caused deaths, injuries or significant impacts.
Excessive Heat: Heat at or above the local excessive heat warning criteria, or heat that caused deaths.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Arizona in 2023 Every state in 2023 This day in weather history Warnings in Arizona, August 2023

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 1214048, 1214049, 1214050, 1215524, 1214052, 1214054, 1214055, 1214057, 1214058, 1218097, 1218098, 1218099, 1218100, 1218102, 1218103, 1218109, 1218110, 1218111, 1218112, 1218113, 1218114, 1218115, 1218117, 1218118.