Alert archive / Illinois / Extreme Heat Warnings
Extreme Heat Warnings in Illinois, 2025
6 extreme heat warnings in 2025. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of extreme heat warnings reaches back to 2005.
Extreme Heat Warnings by county
Each county as a circle sized by its count in 2025. Tap one for its archive.
- Extreme Heat Warnings
- 6
- Busiest month
- July4 extreme heat warnings
- Busiest day
- June 20, 20252 extreme heat warnings
Over time
By month
The alerts
Every alert, in the order issued. Times are local, Central Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 20, 3:50 AM CDT | Extreme Heat Warning | LOT | Cook | 4 days |
| Jun 20, 2:00 PM CDT | Extreme Heat Warning | LSX | Jersey, Madison, Monroe, Saint Clair | 3 days |
| Jul 18, 2:06 PM CDT | Extreme Heat Warning | LSX | Bond, Clinton, Madison, Marion, Monroe, Randolph and 2 more | 12 days |
| Jul 19, 2:48 AM CDT | Extreme Heat Warning | PAH | Alexander, Franklin, Jackson, Johnson, Massac, Perry and 3 more | 6 days |
| Jul 27, 1:44 PM CDT | Extreme Heat Warning | DVN | Hancock, Henderson, Henry, McDonough, Mercer, Rock Island and 1 more | 30 hr |
| Jul 27, 1:50 PM CDT | Extreme Heat Warning | PAH | Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more | 3 days |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Madison County2
- Monroe County2
- Saint Clair County2
- Alexander County2
- Franklin County2
- Jackson County2
- Johnson County2
- Massac County2
- Perry County2
- Pulaski County2
- Union County2
- Williamson County2
- Cook County1
- Jersey County1
- Bond County1
- Clinton County1
- Marion County1
- Randolph County1
- Washington County1
- Hancock County1
- Henderson County1
- Henry County1
- McDonough County1
- Mercer County1
- Rock Island County1
- Warren County1
- Edwards County1
- Gallatin County1
- Hamilton County1
- Hardin County1
- Jefferson County1
- Pope County1
- Saline County1
- Wabash County1
- Wayne County1
- White County1
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20242026
Sources
National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.