Arizona, 2023

Excessive Heat and Heat in Arizona, August 16, 2023

August 16, 2023 · NWS TWC · 3 events in 3 counties and zones

Very hot temperatures were observed across southeast Arizona August 16. Both high and low temperatures were 4 to 9 degrees above normal causing the Moderate to Major Heat Risk categories to be reached.

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.

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  • Tropical storms and surge
  • Floods
  • Wind
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  • Winter weather
  • Heat and drought
  • Cold
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  • Marine and coastal
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Open the live radar over this ground

The toll

Deaths
6
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.

Very hot temperatures were observed across southeast Arizona August 16. Both high and low temperatures were 4 to 9 degrees above normal causing the Moderate to Major Heat Risk categories to be reached. A total of six heat-related fatalities were reported by the Pima County Medical Examiner.

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 Aug 16, 2:47 AM MST, 6 hours 13 minutes earlier.

Area forecast discussion, Aug 16, 2:47 AM MST, 6 hours 13 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

2 excessive heat, 1 heat. Local standard time, as filed.

Excessive Heat, Western Pima County

When
August 16, 9:00 AM MST to 8:00 PM MST
Where
Western Pima County forecast zone
Deaths
1 direct, 0 indirect
Reported by
County Official
Coordinates
32.097, -111.790 (the zone’s center; the record gives no point)

Very hot temperatures 4 to 6 degrees above normal caused the Major Heat Risk category to be reached across western Pima County. The low temperature at Organ Pipe Cactus National Monument was 85 degrees and the high was 110. The Pima County Medical Examiner determined that heat was the primary cause of death for one individual found in the desert near Lukeville.

Excessive Heat, Tucson Metro Area

When
August 16, 9:00 AM MST to 8:00 PM MST
Where
Tucson Metro Area forecast zone
Deaths
2 direct, 2 indirect
Reported by
County Official
Coordinates
32.097, -111.790 (the zone’s center; the record gives no point)

Very hot temperatures around 9 degrees above normal caused the Major Heat Risk category to be reached across eastern Pima County. The low temperature at the Tucson International Airport was 84 degrees and the high was 108. The Pima County Medical Examiner determined that heat was the primary cause of death for two individuals in Tucson. Heat was determined to be a contributing factor in the deaths of two others (one outdoors who had a complicating factor of drug toxicity; and an elderly individual in a vehicle who had other health issues).

Heat, Upper San Pedro River Valley

When
August 16, 10:00 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 4 to 7 degrees above normal, in the upper 90s, caused the Moderate Heat Risk category to be reached across southern Cochise County. The Pima County Medical Examiner determined that heat was the primary cause of death for one individual found in the desert near the International Border.

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.

EventDateAgeSexWhereKind
Excessive Heat, Western Pima County2023-08-16MaleOutside/Open AreasDirect
Excessive Heat, Tucson Metro Area2023-08-1646MaleOutside/Open AreasIndirect
Excessive Heat, Tucson Metro Area2023-08-1644MaleVehicle/Towed TrailerDirect
Excessive Heat, Tucson Metro Area2023-08-1691FemaleVehicle/Towed TrailerIndirect
Excessive Heat, Tucson Metro Area2023-08-1660MaleOutside/Open AreasDirect
Heat, Upper San Pedro River Valley2023-08-1660MaleOutside/Open AreasDirect

What these are

Excessive Heat
Heat at or above the local excessive heat warning criteria, or heat that caused deaths.
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 2023Every state in 2023This day in weather historyWarnings 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 2026-09-30. Each event’s entry at NCEI: 1138782, 1138795, 1138787.