Alert archive / Illinois / Severe Thunderstorm Watches / 2025
Severe Thunderstorm Watches in Illinois, August 2025
4 severe thunderstorm watches in August 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 severe thunderstorm watches reaches back to 1997.
Severe Thunderstorm Watches by county
Each county as a circle sized by its count in August 2025. Tap one for its archive.
- Severe Thunderstorm Watches
- 4
- Busiest day
- August 15, 20252 severe thunderstorm watches
Over time
By day
Days in UTC, the clock the archive keeps.
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 |
|---|---|---|---|---|
| Aug 15, 2:16 PM CDT | Severe Thunderstorm Watch | SPC | Carroll, Henry, Jo Daviess, Mercer, Rock Island, Whiteside | 6 hr |
| Aug 15, 6:46 PM CDT | Severe Thunderstorm Watch | SPC | Bureau, Knox, LaSalle, Lee, Marshall, Ogle and 6 more | 2 hr |
| Aug 16, 1:56 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Cook, DeKalb, DuPage, Kane, Kendall and 6 more | 5 hr |
| Aug 18, 12:13 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 15 more | 9 hr |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Ogle County3
- Carroll County2
- Henry County2
- Jo Daviess County2
- Whiteside County2
- Bureau County2
- LaSalle County2
- Lee County2
- Putnam County2
- Boone County2
- Cook County2
- DeKalb County2
- DuPage County2
- Kane County2
- Kendall County2
- Lake County2
- McHenry County2
- Stephenson County2
- Will County2
- Winnebago County2
- Mercer County1
- Rock Island County1
- Knox County1
- Marshall County1
- Peoria County1
- Stark County1
- Tazewell County1
- Warren County1
- Woodford County1
- Grundy County1
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.