Arizona, 2020

Heat in Arizona, September 29, 2020

September 29, 2020 · NWS TWC · 2 events in 2 counties and zones

Hot temperatures were experienced on September 29th with high temperatures around 100 degrees in southeastern Pima County. The Pima County Medical Examiner confirmed that heat was the primary cause of death for two males found in the desert, one near Three Points and another on the Tohono O'odham Nation southeast of San Miguel.

Where it happened

Every event with a place to put it; 2 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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The toll

Deaths
2
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
2

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.

Hot temperatures were experienced on September 29th with high temperatures around 100 degrees in southeastern Pima County. The Pima County Medical Examiner confirmed that heat was the primary cause of death for two males found in the desert, one near Three Points and another on the Tohono O'odham Nation southeast of San Miguel.

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 Sep 29, 3:21 AM MST, 7 hours 39 minutes earlier.

Area forecast discussion, Sep 29, 3:21 AM MST, 7 hours 39 minutes before
Area Forecast Discussion
National Weather Service Tucson AZ
321 AM MST Tue Sep 29 2020

.SYNOPSIS...High pressure will push temperatures back to near
record levels the second half of the week into the weekend.

&&

.DISCUSSION...Our weather will be dominated by a strong ridge of
high pressure from the west coast into the Great Basin and desert
southwest for the next 7 days. That will mean dry conditions with
afternoon highs running 8 to 12 degrees above average.

The hottest days will be Wednesday through Saturday with near
record highs and Tucson continuing to flirt with adding 100 degree
days to the total for the year. We currently stand at 98, only 1
behind the record of 99. October is going to start out way above
average, following what is now guaranteed to be the warmest
September on record. The all time record hottest temperature in
October is 102, and that will be threatened Thursday and/or
Friday.

&&

.AVIATION...Valid through 30/12Z.
Clear skies. Surface winds out of the east and southeast at 12 to
18 kts this morning, diminishing this afternoon. Aviation
discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Dry conditions and warmer than normal for the next
7 days. 20-ft winds will be easterly through Wednesday morning then
settle into normal diurnal trends Wednesday afternoon into the
weekend. Wind speeds will be elevated this morning. Min RH values
will be in the low teens today then drop into the single digits
for some locales Wednesday through the weekend.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
None.
&&

Meyer/Rasmussen

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson

The radar

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

Open the radar archive at this moment

Event by event

2 heat. Local standard time, as filed.

Heat, Tohono O Odham Nation

When
September 29, 11:00 AM MST to 7:00 PM MST
Where
Tohono O Odham Nation forecast zone
Deaths
1 direct, 0 indirect
Reported by
County Official
Coordinates
32.501, -111.567 (the zone’s center; the record gives no point)

Temperatures 9 to 13 degrees above normal around 100 degrees occurred in southeastern Pima County causing the Moderate Heat Risk category to be reached on September 29th. The Pima County Medical Examiner confirmed that heat was the primary cause of death for two males, one 10 miles southeast of San Miguel on the Tohono O'odham Nation and another near Three Points.

Heat, Tucson Metro Area

When
September 29, 11:00 AM MST to 7:00 PM MST
Where
Tucson Metro Area 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)

Temperatures 9 to 13 degrees above normal around 100 degrees occurred in southeastern Pima County causing the Moderate Heat Risk category to be reached on September 29th. The Pima County Medical Examiner confirmed that heat was the primary cause of death for two males, one 10 miles southeast of San Miguel on the Tohono O'odham Nation and another near Three Points.

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
Heat, Tohono O Odham Nation2020-09-2922MaleOutside/Open AreasDirect
Heat, Tucson Metro Area2020-09-2938MaleOutside/Open AreasDirect

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 2020Every state in 2020This day in weather historyWarnings in Arizona, September 2020

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 2026-09-24. Each event’s entry at NCEI: 922403, 922404.