Alert archive / Illinois / Severe Thunderstorm Watches / 2021
Severe Thunderstorm Watches in Illinois, August 2021
10 severe thunderstorm watches in August 2021. 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 2021. Tap one for its archive.
- Severe Thunderstorm Watches
- 10
- Busiest day
- August 10, 20212 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 8, 12:44 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Bond, Brown, Calhoun, Clinton, Fayette and 11 more | 7 hr |
| Aug 10, 2:08 PM CDT | Severe Thunderstorm Watch | SPC | Henderson, Mercer, Rock Island, Warren | 6 hr |
| Aug 10, 3:47 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 15 more | 6 hr |
| Aug 10, 7:38 PM CDT | Severe Thunderstorm Watch | SPC | Kankakee | 5 hr |
| Aug 11, 8:52 AM CDT | Severe Thunderstorm Watch | SPC | Cook, DeKalb, DuPage, Grundy, Kane, Kankakee and 6 more | 4 hr |
| Aug 11, 8:22 PM CDT | Severe Thunderstorm Watch | SPC | Bureau, Cook, DeKalb, DuPage, Ford, Grundy and 11 more | 8 hr |
| Aug 12, 5:19 PM CDT | Severe Thunderstorm Watch | SPC | Calhoun, Clinton, Greene, Jersey, Macoupin, Madison and 7 more | 5 hr |
| Aug 12, 7:37 PM CDT | Severe Thunderstorm Watch | SPC | Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more | 4 hr |
| Aug 24, 1:52 PM CDT | Severe Thunderstorm Watch | SPC | Carroll, Jo Daviess, Rock Island, Stephenson, Whiteside | 5 hr |
| Aug 24, 3:55 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Cook, DeKalb, DuPage, Kane, Lake and 4 more | 5 hr |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Cook County4
- DeKalb County4
- DuPage County4
- Kane County4
- Lake County4
- Lee County4
- Grundy County3
- Kendall County3
- LaSalle County3
- McHenry County3
- Ogle County3
- Will County3
- Kankakee County3
- Calhoun County2
- Clinton County2
- Greene County2
- Jersey County2
- Macoupin County2
- Madison County2
- Marion County2
- Monroe County2
- Randolph County2
- Saint Clair County2
- Washington County2
- Rock Island County2
- Boone County2
- Bureau County2
- Carroll County2
- Jo Daviess County2
- Putnam County2
- Stephenson County2
- Whiteside County2
- Winnebago County2
- Adams County1
- Bond County1
- Brown County1
- Fayette County1
- Montgomery County1
- Pike County1
- Henderson County1
24 more counties
- Mercer County1
- Warren County1
- Henry County1
- Ford County1
- Iroquois County1
- Livingston County1
- Morgan County1
- Scott County1
- Alexander County1
- Franklin County1
- Gallatin County1
- Hamilton County1
- Hardin County1
- Jackson County1
- Jefferson County1
- Johnson County1
- Massac County1
- Perry County1
- Pope County1
- Pulaski County1
- Saline County1
- Union County1
- White County1
- Williamson County1
Nearby
Alerts in force nowTornadoes on recordThe radar archive20202022
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. Rebuilt daily.