Arizona, 2020

Excessive Heat in Arizona, May 28 to 31, 2020

May 28 to 31, 2020 · NWS TWC · 8 events in 8 counties and zones

Very hot temperatures were experienced in parts of southeast Arizona May 28th through the 31st with high temperatures exceeding established records in many locations. No heat-related fatalities were reported.

Where it happened

Every event with a place to put it; 8 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
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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
8

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 experienced in parts of southeast Arizona May 28th through the 31st with high temperatures exceeding established records in many locations. No heat-related fatalities were reported.

The radar

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

Open the radar archive at this moment

Event by event

8 excessive heat. Local standard time, as filed.

Excessive Heat, Western Pima County

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
Western Pima County forecast zone
Reported by
Mesonet
Coordinates
32.097, -111.790 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

Excessive Heat, Tohono O Odham Nation

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
Tohono O Odham Nation forecast zone
Reported by
Mesonet
Coordinates
32.501, -111.567 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

Excessive Heat, Upper Santa Cruz River and Altar Valleys

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
Upper Santa Cruz River and Altar Valleys forecast zone
Reported by
Mesonet
Coordinates
31.812, -111.318 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

Excessive Heat, Tucson Metro Area

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
Tucson Metro Area forecast zone
Reported by
Mesonet
Coordinates
32.097, -111.790 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

Excessive Heat, South Central Pinal County

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
South Central Pinal County forecast zone
Reported by
Mesonet
Coordinates
32.904, -111.345 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

Excessive Heat, Southeast Pinal County

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
Southeast Pinal County forecast zone
Reported by
Mesonet
Coordinates
32.904, -111.345 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

Excessive Heat, Upper San Pedro River Valley

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
Upper San Pedro River Valley forecast zone
Reported by
Mesonet
Coordinates
32.109, -110.569 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

Excessive Heat, Upper Gila River and Aravaipa Valleys

When
May 28, 12:00 PM MST to May 31, 8:00 PM MST
Where
Upper Gila River and Aravaipa Valleys forecast zone
Reported by
Mesonet
Coordinates
33.074, -109.563 (the zone’s center; the record gives no point)

Very hot temperatures 7 to 13 degrees above normal occurred in parts of southeast Arizona, causing the High Heat Risk category to be reached. Several daily high temperature records were tied or broken. Record highs included: May 28th, 107 degrees (tie) at Ajo and 106 at Duncan and Safford Airport; May 29th, 108 degrees at Tucson International Airport, 107 at Fort Thomas and 102 (tie) at San Manuel; May 30th, 111 degrees at Ajo, 109 at Picacho and 106 (tie) at Anvil Ranch; May 31st, 106 degrees (tie) at Green Valley. On May 29th, Sells reached 108 degrees, which was two degrees shy of a record while Picacho topped out at 110, just one degree off the record for the date.

What these are

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

More

Every storm in Arizona in 2020Every state in 2020This day in weather historyWarnings in Arizona, May 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 2026-09-30. Each event’s entry at NCEI: 895856, 895876, 895877, 895878, 895879, 895880, 895881, 895882.