Name: Heat in Arizona, July 30 to 31, 2023
Start: 2023-07-30T11:00
End: 2023-07-31T22:00
Location: Arizona

Where it happened

Every event with a place to put it; 3 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: 4
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 3

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 TWC wrote it up.

Strong high pressure continued to create hot temperatures 2 to 8 degrees above normal July 30-31 in parts of southeast Arizona and caused the Moderate Heat Risk category to be reached. A total of 5 heat-related fatalities were reported by the Pima County Medical Examiner in Pima and Cochise counties.

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 Tucson, AZ wrote its last area forecast discussion before the first event at Jul 30, 9:04 AM MST, 1 hour 56 minutes earlier.

Area forecast discussion, Jul 30, 9:04 AM MST, 1 hour 56 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

3 heat. Local standard time, as filed.

Heat, Eastern Cochise County Below 5000 Feet

When: July 30, 11:00 AM MST to 8:00 PM MST
Where: Eastern Cochise County Below 5000 Feet forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 31.880, -109.751 (the zone’s center; the record gives no point)

Hot temperatures 6 to 8 degrees above normal caused the Moderate Heat Risk category to be reached in the Sierra Vista area where temperatures topped out near 100 degrees. The Pima County Medical Examiner determined heat to be the primary cause of death for one individual found in the desert 25 miles northeast of Douglas.

Heat, Tucson Metro Area

When: July 31, 11:00 AM MST to 10:00 PM MST
Where: Tucson Metro Area forecast zone
Deaths: 1 direct, 1 indirect
Reported by: County Official
Coordinates: 32.097, -111.790 (the zone’s center; the record gives no point)

Hot temperatures 2 to 4 degrees above normal caused the Moderate Heat Risk category to be reached in the Tucson Metro area where temperatures topped out between 98 and 102. The Pima County Medical Examiner determined heat to be the primary cause of death for one individual who was found in the car in which he was living in southwest Tucson. Heat was found to be a contributing factor in the death of another person who died in their Oro Valley home in which the A/C unit was either broken or turned off. Heart disease was a complicating factor in this fatality.

Heat, Upper San Pedro River Valley

When: July 31, 11:00 AM MST to 8:00 PM MST
Where: Upper San Pedro River Valley forecast zone
Deaths: 1 direct, 0 indirect
Reported by: County Official
Coordinates: 32.109, -110.569 (the zone’s center; the record gives no point)

Hot temperatures 3 to 5 degrees above normal caused the Moderate Heat Risk category to be reached in the Sierra Vista area where temperatures reached the mid to upper 90s. The Pima County Medical Examiner determined heat to be the primary cause of death for an elderly man who died on a hiking trail.

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	Age	Sex	Where	Kind
Heat, Eastern Cochise County Below 5000 Feet	2023-07-30	21	Male	Outside/Open Areas	Direct
Heat, Tucson Metro Area	2023-07-31	55	Male	Permanent Home	Indirect
Heat, Tucson Metro Area	2023-07-31	71	Male	Vehicle/Towed Trailer	Direct
Heat, Upper San Pedro River Valley	2023-07-31	88	Male	Outside/Open Areas	Direct

What these are

Heat: Heat below excessive heat criteria that still caused deaths, injuries or significant impacts.

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

The same day elsewhere

More

Every storm in Arizona in 2023 Every state in 2023 This day in weather history Warnings in Arizona, July 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: 1127708, 1127676, 1127693.