Excessive Heat and Heat in Illinois, July 23 to 24, 2025

Name: Excessive Heat and Heat in Illinois, July 23 to 24, 2025
Start: 2025-07-23T11:00
End: 2025-07-24T15:00
Location: Illinois

July 23 to 24, 2025 · NWS LOT · 18 events in 16 counties and zones

On July 23rd, high temperatures reached the lower 90s with peak heat index values generally in the 105 degree range for most areas, though a few areas peaked around 110 degrees. On July 24th, high temperatures reached the upper 80s and lower 90s with peak heat index values generally in the 100 degree range for most areas, though a few areas peaked around 105 degrees.

Where it happened

Every event with a place to put it; 18 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: 18

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 LOT wrote it up.

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 Chicago, IL wrote its last area forecast discussion before the first event at Jul 23, 5:34 AM CST, 5 hours 26 minutes earlier.

Area forecast discussion, Jul 23, 5:34 AM CST, 5 hours 26 minutes before

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Hazardous weather outlook, Jul 23, 7:23 AM CST, 3 hours 37 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

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

Heat, La Salle

When: July 23, 11:00 AM CST to 6:00 PM CST
Where: La Salle forecast zone
Reported by: AWOS
Coordinates: 41.344, -88.886 (the zone’s center; the record gives no point)

Heat, Grundy

When: July 23, 12:00 PM CST to 6:00 PM CST
Where: Grundy forecast zone
Reported by: AWOS
Coordinates: 41.285, -88.418 (the zone’s center; the record gives no point)

Heat, Southern Will County

When: July 23, 12:00 PM CST to 6:00 PM CST
Where: Southern Will County forecast zone
Reported by: AWOS
Coordinates: 41.445, -87.979 (the zone’s center; the record gives no point)

Heat, Kane

When: July 23, 1:00 PM CST to 6:00 PM CST
Where: Kane forecast zone
Reported by: ASOS
Coordinates: 41.939, -88.429 (the zone’s center; the record gives no point)

Heat, Kendall

When: July 23, 1:00 PM CST to 6:00 PM CST
Where: Kendall forecast zone
Reported by: ASOS
Coordinates: 41.591, -88.429 (the zone’s center; the record gives no point)

Excessive Heat, Northern Will County

When: July 23, 1:00 PM CST to 7:00 PM CST
Where: Northern Will County forecast zone
Reported by: AWOS
Coordinates: 41.445, -87.979 (the zone’s center; the record gives no point)

Heat, Du Page

When: July 23, 1:00 PM CST to 6:00 PM CST
Where: Du Page forecast zone
Reported by: ASOS
Coordinates: 41.852, -88.086 (the zone’s center; the record gives no point)

Heat, De Kalb

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: De Kalb forecast zone
Reported by: AWOS
Coordinates: 41.894, -88.770 (the zone’s center; the record gives no point)

Heat, Livingston

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: Livingston forecast zone
Reported by: AWOS
Coordinates: 40.892, -88.558 (the zone’s center; the record gives no point)

Heat, Ford

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: Ford forecast zone
Reported by: AWOS
Coordinates: 40.597, -88.223 (the zone’s center; the record gives no point)

Heat, Iroquois

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: Iroquois forecast zone
Reported by: AWOS
Coordinates: 40.747, -87.824 (the zone’s center; the record gives no point)

Heat, Kankakee

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: Kankakee forecast zone
Reported by: AWOS
Coordinates: 41.138, -87.862 (the zone’s center; the record gives no point)

Heat, Eastern Will County

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: Eastern Will County forecast zone
Reported by: AWOS
Coordinates: 41.445, -87.979 (the zone’s center; the record gives no point)

Heat, Southern Cook County

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: Southern Cook County forecast zone
Reported by: AWOS
Coordinates: 41.895, -87.646 (the zone’s center; the record gives no point)

Heat, Northern Cook County

When: July 23, 2:00 PM CST to 6:00 PM CST
Where: Northern Cook County forecast zone
Reported by: ASOS
Coordinates: 41.895, -87.646 (the zone’s center; the record gives no point)

Heat, Central Cook County

When: July 23, 3:00 PM CST to 7:00 PM CST
Where: Central Cook County forecast zone
Reported by: ASOS
Coordinates: 41.895, -87.646 (the zone’s center; the record gives no point)

Heat, Northern Will County

When: July 24, 11:00 AM CST to 3:00 PM CST
Where: Northern Will County forecast zone
Reported by: AWOS
Coordinates: 41.445, -87.979 (the zone’s center; the record gives no point)

Heat, Grundy

When: July 24, 12:00 PM CST to 3:00 PM CST
Where: Grundy forecast zone
Reported by: AWOS
Coordinates: 41.285, -88.418 (the zone’s center; the record gives no point)

What these are

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

Every storm in Illinois in 2025 Every state in 2025 This day in weather history Warnings in Illinois, July 2025

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: 1281412, 1281414, 1281420, 1281411, 1281413, 1281421, 1281423, 1281410, 1281415, 1281416, 1281417, 1281418, 1281419, 1281422, 1281425, 1281424, 1281426, 1281427.