Iowa, 2024

Excessive Heat and Heat in Iowa, July 31, 2024

July 31, 2024 · NWS FSD · 11 events in 11 counties and zones

Pooling moisture ahead of a frontal boundary pushed dew point readings into the upper 70s and lower 80s, and temperatures in the upper 80s to lower 90s produced heat index values from 100 to 113 degrees.

Where it happened

Every event with a place to put it; 11 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
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
11

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 FSD wrote it up.

Pooling moisture ahead of a frontal boundary pushed dew point readings into the upper 70s and lower 80s, and temperatures in the upper 80s to lower 90s produced heat index values from 100 to 113 degrees.

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 Sioux Falls, SD wrote its last area forecast discussion before the first event at Jul 31, 10:37 AM CST, 23 minutes earlier.

Area forecast discussion, Jul 31, 10:37 AM CST, 23 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

8 excessive heat, 3 heat. Local standard time, as filed.

Excessive Heat, Lyon

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Lyon forecast zone
Reported by
Mesonet
Coordinates
43.381, -96.210 (the zone’s center; the record gives no point)

Heat index values reached 106 degrees near George.

Excessive Heat, Osceola

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Osceola forecast zone
Reported by
Mesonet
Coordinates
43.379, -95.624 (the zone’s center; the record gives no point)

Heat index values reached 107 degrees near Ashton.

Excessive Heat, O'Brien

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
O'Brien forecast zone
Reported by
Mesonet
Coordinates
43.084, -95.625 (the zone’s center; the record gives no point)

Heat index values reached 107 degrees near Sutherland and 106 degrees near Hartley.

Excessive Heat, Sioux

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Sioux forecast zone
Reported by
Mesonet
Coordinates
43.083, -96.178 (the zone’s center; the record gives no point)

Heat index values reached 109 degrees near Hawarden.

Excessive Heat, Plymouth

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Plymouth forecast zone
Reported by
AWOS
Coordinates
42.738, -96.214 (the zone’s center; the record gives no point)

Heat index values reached 111 degrees near Sioux City, 109 degrees near Westfield, and 108 degrees at Remsen and Le Mars.

Excessive Heat, Cherokee

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Cherokee forecast zone
Reported by
Mesonet
Coordinates
42.736, -95.624 (the zone’s center; the record gives no point)

Heat index values reached 106 degrees at Marcus.

Excessive Heat, Buena Vista

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Buena Vista forecast zone
Reported by
Mesonet
Coordinates
42.736, -95.151 (the zone’s center; the record gives no point)

Heat index values reached 111 degrees near Alta and 105 degrees near Rembrandt.

Excessive Heat, Woodbury

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Woodbury forecast zone
Reported by
Mesonet
Coordinates
42.390, -96.045 (the zone’s center; the record gives no point)

Heat index values reached 112 degrees near Washta, 111 degrees at Moville, and 106 degrees in Sioux City.

Heat, Dickinson

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Dickinson forecast zone
Reported by
Mesonet
Coordinates
43.378, -95.151 (the zone’s center; the record gives no point)

Heat index values reached 102 degrees at Milford and 100 degrees in Terril and 5 miles southwest of Milford.

Heat, Clay

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Clay forecast zone
Reported by
Department of Highways
Coordinates
43.083, -95.151 (the zone’s center; the record gives no point)

Heat index values reached 100 degrees near Spencer.

Heat, Ida

When
July 31, 11:00 AM CST to 6:00 PM CST
Where
Ida forecast zone
Reported by
Department of Highways
Coordinates
42.387, -95.513 (the zone’s center; the record gives no point)

Heat index values reached 104 degrees in Battle Creek and Ida Grove.

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 Iowa in 2024Every state in 2024This day in weather historyWarnings in Iowa, July 2024

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: 1206139, 1206140, 1206141, 1206142, 1206143, 1206144, 1206145, 1206146, 1206147, 1206148, 1206149.