Alert archive / Illinois / Severe Thunderstorm Warnings / 2026
Severe Thunderstorm Warnings in Illinois, August 2026
118 severe thunderstorm warnings in August 2026. 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 warnings reaches back to 1986.
Severe Thunderstorm Warnings by county
Each county as a circle sized by its count in August 2026. Tap one for its archive.
- Severe Thunderstorm Warnings
- 118
- Busiest day
- August 11, 202624 severe thunderstorm warnings
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 |
|---|---|---|---|---|
| Jul 31, 11:52 PM CDT | Severe Thunderstorm Warning | PAH | Alexander, Pulaski | 23 min |
| Aug 7, 10:47 PM CDT | Severe Thunderstorm Warning | LSX | Adams | 32 min |
| Aug 9, 1:03 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Kane | 57 min |
| Aug 9, 1:36 PM CDT | Severe Thunderstorm Warning | LOT | DuPage, Kane, Kendall, Will | 54 min |
| Aug 9, 2:51 PM CDT | Severe Thunderstorm Warning | LOT | Cook | 24 min |
| Aug 9, 2:51 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Will | 24 min |
| Aug 9, 3:14 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Will | 76 min |
| Aug 9, 8:41 PM CDT | Severe Thunderstorm Warning | LOT | Lee | 64 min |
| Aug 9, 8:57 PM CDT | Severe Thunderstorm Warning | DVN | Bureau, Henry | 33 min |
| Aug 9, 9:39 PM CDT | Severe Thunderstorm Warning | LOT | Lee | 66 min |
| Aug 9, 11:22 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Lake | 38 min |
| Aug 9, 11:35 PM CDT | Severe Thunderstorm Warning | LOT | Grundy, LaSalle, Livingston | 70 min |
| Aug 10, 12:36 AM CDT | Severe Thunderstorm Warning | LOT | Ford, Grundy, Iroquois, Kankakee, Livingston | 69 min |
| Aug 10, 1:20 AM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois | 55 min |
| Aug 10, 1:42 AM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois, Livingston | 93 min |
| Aug 11, 3:11 AM CDT | Severe Thunderstorm Warning | LOT | Boone, McHenry | 51 min |
| Aug 11, 3:49 AM CDT | Severe Thunderstorm Warning | LOT | Lake, McHenry | 27 min |
| Aug 11, 8:15 AM CDT | Severe Thunderstorm Warning | DVN | Carroll, Jo Daviess, Stephenson | 60 min |
| Aug 11, 8:20 AM CDT | Severe Thunderstorm Warning | DVN | Rock Island, Whiteside | 43 min |
| Aug 11, 8:33 AM CDT | Severe Thunderstorm Warning | DVN | Carroll, Whiteside | 72 min |
| Aug 11, 8:43 AM CDT | Severe Thunderstorm Warning | DVN | Jo Daviess, Stephenson | 51 min |
| Aug 11, 8:45 AM CDT | Severe Thunderstorm Warning | LOT | Lee, Ogle, Winnebago | 90 min |
| Aug 11, 8:54 AM CDT | Severe Thunderstorm Warning | DVN | Bureau, Henry, Rock Island | 81 min |
| Aug 11, 9:22 AM CDT | Severe Thunderstorm Warning | LOT | Boone, DeKalb, LaSalle | 53 min |
| Aug 11, 9:34 AM CDT | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 42 min |
| Aug 11, 9:38 AM CDT | Severe Thunderstorm Warning | LOT | Kane, McHenry | 67 min |
| Aug 11, 9:44 AM CDT | Severe Thunderstorm Warning | ILX | Marshall | 46 min |
| Aug 11, 9:48 AM CDT | Severe Thunderstorm Warning | LOT | Grundy, Kendall, LaSalle, Livingston | 72 min |
| Aug 11, 10:17 AM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Kane, Kendall, Will | 58 min |
| Aug 11, 10:20 AM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Kankakee, Will | 55 min |
| Aug 11, 10:49 AM CDT | Severe Thunderstorm Warning | LOT | Kankakee, Will | 56 min |
| Aug 11, 11:10 AM CDT | Severe Thunderstorm Warning | LOT | Iroquois | 65 min |
| Aug 11, 1:56 PM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois | 34 min |
| Aug 11, 1:57 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Vermilion | 63 min |
| Aug 11, 2:50 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, McLean, Piatt | 40 min |
| Aug 11, 3:17 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Piatt | 43 min |
| Aug 11, 3:52 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Douglas, Edgar, Vermilion | 53 min |
| Aug 11, 4:22 PM CDT | Severe Thunderstorm Warning | ILX | Clark, Edgar | 38 min |
| Aug 11, 5:30 PM CDT | Severe Thunderstorm Warning | ILX | Clark | 45 min |
| Aug 12, 6:09 AM CDT | Severe Thunderstorm Warning | DVN | Rock Island | 66 min |
| Aug 12, 6:53 AM CDT | Severe Thunderstorm Warning | DVN | Henry, Rock Island | 67 min |
| Aug 12, 7:22 AM CDT | Severe Thunderstorm Warning | DVN | Bureau, Henry, Whiteside | 53 min |
| Aug 12, 7:27 AM CDT | Severe Thunderstorm Warning | DVN | Henderson | 63 min |
| Aug 12, 7:44 AM CDT | Severe Thunderstorm Warning | ILX | Knox | 61 min |
| Aug 12, 7:49 AM CDT | Severe Thunderstorm Warning | DVN | Henry, Mercer | 41 min |
| Aug 12, 7:53 AM CDT | Severe Thunderstorm Warning | LOT | Lee, Ogle | 66 min |
| Aug 12, 7:54 AM CDT | Severe Thunderstorm Warning | DVN | Hancock | 36 min |
| Aug 12, 8:11 AM CDT | Severe Thunderstorm Warning | DVN | Bureau, Putnam, Whiteside | 49 min |
| Aug 12, 8:20 AM CDT | Severe Thunderstorm Warning | DVN | Hancock, Henderson, McDonough, Warren | 55 min |
| Aug 12, 8:23 AM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 66 min |
| Aug 12, 8:25 AM CDT | Severe Thunderstorm Warning | ILX | Marshall, Stark | 53 min |
| Aug 12, 8:31 AM CDT | Severe Thunderstorm Warning | LOT | DeKalb, Lee, Ogle | 57 min |
| Aug 12, 9:03 AM CDT | Severe Thunderstorm Warning | LOT | Grundy, Kane, Kendall | 46 min |
| Aug 12, 9:26 AM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Kankakee, Will | 64 min |
| Aug 12, 10:14 AM CDT | Severe Thunderstorm Warning | LOT | Iroquois, Kankakee | 61 min |
| Aug 12, 10:35 AM CDT | Severe Thunderstorm Warning | ILX | Vermilion | 40 min |
| Aug 12, 1:39 PM CDT | Severe Thunderstorm Warning | ILX | Crawford, Lawrence | 12 min |
| Aug 12, 3:58 PM CDT | Severe Thunderstorm Warning | LSX | Randolph | 47 min |
| Aug 12, 4:44 PM CDT | Severe Thunderstorm Warning | LSX | Randolph | 29 min |
| Aug 12, 5:16 PM CDT | Severe Thunderstorm Warning | PAH | Franklin, Hamilton, Jefferson | 44 min |
| Aug 12, 6:43 PM CDT | Severe Thunderstorm Warning | LSX | Randolph | 62 min |
| Aug 12, 9:04 PM CDT | Severe Thunderstorm Warning | PAH | Alexander, Johnson, Massac, Pulaski | 41 min |
| Aug 13, 12:09 PM CDT | Severe Thunderstorm Warning | ILX | Fulton, Logan, Mason, Peoria, Tazewell | 66 min |
| Aug 13, 12:31 PM CDT | Severe Thunderstorm Warning | ILX | McLean, Peoria, Tazewell, Woodford | 44 min |
| Aug 13, 12:50 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Logan, McLean, Macon, Woodford | 55 min |
| Aug 13, 1:25 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, DeWitt, McLean, Piatt, Vermilion | 65 min |
| Aug 13, 1:28 PM CDT | Severe Thunderstorm Warning | LOT | Ford | 47 min |
| Aug 13, 1:56 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Douglas, Edgar, Piatt, Vermilion | 64 min |
| Aug 13, 2:22 PM CDT | Severe Thunderstorm Warning | ILX | Vermilion | 39 min |
| Aug 13, 2:59 PM CDT | Severe Thunderstorm Warning | ILX | Edgar, Vermilion | 22 min |
| Aug 13, 5:10 PM CDT | Severe Thunderstorm Warning | ILX | Crawford | 37 min |
| Aug 14, 12:05 AM CDT | Severe Thunderstorm Warning | ILX | Champaign, Vermilion | 55 min |
| Aug 14, 12:18 AM CDT | Severe Thunderstorm Warning | ILX | Peoria, Tazewell, Woodford | 57 min |
| Aug 14, 1:12 AM CDT | Severe Thunderstorm Warning | ILX | McLean | 52 min |
| Aug 14, 2:33 AM CDT | Severe Thunderstorm Warning | ILX | Champaign, Piatt, Vermilion | 46 min |
| Aug 14, 11:11 PM CDT | Severe Thunderstorm Warning | DVN | Hancock | 64 min |
| Aug 15, 12:02 AM CDT | Severe Thunderstorm Warning | DVN | Hancock | 58 min |
| Aug 15, 12:31 AM CDT | Severe Thunderstorm Warning | DVN | Hancock, McDonough | 74 min |
| Aug 15, 1:23 AM CDT | Severe Thunderstorm Warning | ILX | Fulton, Mason | 67 min |
| Aug 15, 1:51 AM CDT | Severe Thunderstorm Warning | ILX | Fulton | 24 min |
| Aug 15, 2:23 AM CDT | Severe Thunderstorm Warning | ILX | Peoria, Tazewell | 38 min |
| Aug 15, 3:43 AM CDT | Severe Thunderstorm Warning | ILX | Cass, Fulton, Mason, Menard, Morgan, Schuyler and 1 more | 62 min |
| Aug 15, 5:41 PM CDT | Severe Thunderstorm Warning | DVN | Hancock | 34 min |
| Aug 15, 9:50 PM CDT | Severe Thunderstorm Warning | DVN | Bureau, Henry, Mercer, Rock Island, Whiteside | 55 min |
| Aug 16, 11:59 AM CDT | Severe Thunderstorm Warning | LSX | Adams, Pike | 46 min |
| Aug 16, 1:25 PM CDT | Severe Thunderstorm Warning | ILX | Christian, Logan, Menard, Sangamon | 35 min |
| Aug 16, 1:55 PM CDT | Severe Thunderstorm Warning | ILX | Christian, DeWitt, Logan, Macon | 50 min |
| Aug 16, 2:55 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Coles, Douglas, Edgar, Vermilion | 50 min |
| Aug 16, 3:25 PM CDT | Severe Thunderstorm Warning | ILX | Clark, Edgar, Vermilion | 50 min |
| Aug 16, 9:17 PM CDT | Severe Thunderstorm Warning | LSX | Madison, Monroe, Saint Clair | 35 min |
| Aug 19, 6:34 PM CDT | Severe Thunderstorm Warning | ILX | Fulton | 56 min |
| Aug 19, 10:35 PM CDT | Severe Thunderstorm Warning | PAH | Union | 25 min |
| Aug 19, 10:55 PM CDT | Severe Thunderstorm Warning | PAH | Alexander, Pulaski, Union | 50 min |
| Aug 19, 10:57 PM CDT | Severe Thunderstorm Warning | PAH | Johnson, Union | 36 min |
| Aug 19, 11:24 PM CDT | Severe Thunderstorm Warning | PAH | Alexander | 51 min |
| Aug 19, 11:44 PM CDT | Severe Thunderstorm Warning | PAH | Alexander, Pulaski | 14 min |
| Aug 20, 12:05 AM CDT | Severe Thunderstorm Warning | PAH | Alexander | 40 min |
| Aug 20, 2:11 AM CDT | Severe Thunderstorm Warning | PAH | Alexander, Pulaski | 42 min |
| Aug 21, 2:17 PM CDT | Severe Thunderstorm Warning | LOT | Boone, DeKalb, McHenry | 43 min |
| Aug 21, 2:57 PM CDT | Severe Thunderstorm Warning | LOT | DeKalb, Kane | 63 min |
| Aug 21, 3:45 PM CDT | Severe Thunderstorm Warning | LOT | Boone, Winnebago | 22 min |
| Aug 21, 3:52 PM CDT | Severe Thunderstorm Warning | DVN | Carroll, Whiteside | 38 min |
| Aug 21, 4:13 PM CDT | Severe Thunderstorm Warning | LOT | Lee | 40 min |
| Aug 21, 4:55 PM CDT | Severe Thunderstorm Warning | LOT | DeKalb, Lee, Ogle | 40 min |
| Aug 21, 5:28 PM CDT | Severe Thunderstorm Warning | DVN | Jo Daviess, Stephenson | 47 min |
| Aug 21, 5:44 PM CDT | Severe Thunderstorm Warning | LOT | DeKalb, LaSalle, Lee | 46 min |
| Aug 21, 6:15 PM CDT | Severe Thunderstorm Warning | DVN | Carroll, Jo Daviess, Stephenson | 60 min |
| Aug 21, 6:29 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 17 min |
| Aug 21, 6:54 PM CDT | Severe Thunderstorm Warning | DVN | Carroll, Whiteside | 66 min |
| Aug 21, 7:20 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 40 min |
| Aug 21, 8:13 PM CDT | Severe Thunderstorm Warning | DVN | Bureau, Henry, Rock Island, Whiteside | 34 min |
| Aug 21, 9:10 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 19 min |
| Aug 21, 9:22 PM CDT | Severe Thunderstorm Warning | DVN | Henry | 23 min |
| Aug 21, 11:17 PM CDT | Severe Thunderstorm Warning | ILX | Fulton, Mason, Menard | 43 min |
| Aug 22, 2:38 AM CDT | Severe Thunderstorm Warning | LSX | Bond, Clinton, Fayette, Macoupin, Madison, Marion and 1 more | 67 min |
| Aug 22, 3:24 AM CDT | Severe Thunderstorm Warning | PAH | Jefferson | 51 min |
| Aug 22, 3:54 AM CDT | Severe Thunderstorm Warning | PAH | Franklin, Hamilton, Jefferson, Wayne | 17 min |
| Aug 26, 3:25 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Vermilion | 42 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Vermilion County12
- Champaign County9
- Cook County8
- Lee County8
- Henry County8
- LaSalle County8
- Whiteside County8
- Alexander County7
- Will County7
- Bureau County7
- DuPage County6
- Kane County6
- Iroquois County6
- Rock Island County6
- DeKalb County6
- Edgar County6
- Hancock County6
- Fulton County6
- Pulaski County5
- Ford County5
- Kankakee County5
- Carroll County5
- McLean County5
- Piatt County5
- Tazewell County5
- Kendall County4
- Grundy County4
- Livingston County4
- Boone County4
- McHenry County4
- Jo Daviess County4
- Stephenson County4
- Ogle County4
- DeWitt County4
- Logan County4
- Mason County4
- Peoria County4
- Douglas County3
- Clark County3
- Randolph County3
39 more counties
- Jefferson County3
- Woodford County3
- Menard County3
- Union County3
- Adams County2
- Lake County2
- Winnebago County2
- Putnam County2
- Marshall County2
- Henderson County2
- Mercer County2
- McDonough County2
- Crawford County2
- Franklin County2
- Hamilton County2
- Johnson County2
- Macon County2
- Christian County2
- Madison County2
- Knox County1
- Warren County1
- Stark County1
- Lawrence County1
- Massac County1
- Cass County1
- Morgan County1
- Schuyler County1
- Pike County1
- Sangamon County1
- Coles County1
- Monroe County1
- Saint Clair County1
- Bond County1
- Clinton County1
- Fayette County1
- Macoupin County1
- Marion County1
- Montgomery County1
- Wayne County1
Nearby
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.