Cook County weather alerts
There are no active weather alerts for Cook County, IL right now.
Since 2016 the National Weather Service has issued about 1,395 alerts that included Cook County, roughly 140 a year. The most common is the flood advisory (329 from 2016 to 2025). The last tornado warning was issued on August 11, 2026. 87 tornadoes have touched down in the county since 1950.
Updated from the National Weather Service · lists refresh hourly; the live map loads current alerts directly from the NWS
No warnings, watches or advisories include Cook County at the moment. This page updates automatically when the National Weather Service issues one. Check neighboring McHenry County, Kane County, Lake County, Will County.
Cook County alert history
Alert events that included Cook County or its forecast zones, from the NWS warning archive.
| Alert type | 2016–2025 | 2026 | Last issued |
|---|---|---|---|
| Flood Advisory | 329 | 52 | November 13, 2026 |
| Severe Thunderstorm Warning | 269 | 64 | August 12, 2026 |
| Flood Warning | 105 | 40 | September 20, 2026 |
| Winter Weather Advisory | 100 | 6 | November 13, 2026 |
| Dense Fog Advisory | 95 | 10 | October 20, 2026 |
| Wind Advisory | 72 | 8 | June 28, 2026 |
| Severe Thunderstorm Watch | 67 | 17 | August 21, 2026 |
| Flash Flood Warning | 62 | 17 | August 1, 2026 |
| Flood Watch | 55 | 15 | October 1, 2026 |
| Tornado Warning | 34 | 10 | August 11, 2026 |
| Frost Advisory | 26 | 3 | May 7, 2026 |
| Cold Weather Advisory | 24 | 3 | January 26, 2026 |
| Tornado Watch | 22 | 4 | June 11, 2026 |
| Winter Storm Watch | 20 | 1 | January 31, 2026 |
| Winter Storm Warning | 18 | 2 | January 30, 2026 |
| Freeze Warning | 16 | 1 | April 20, 2026 |
| Heat Advisory | 15 | 4 | September 4, 2026 |
| High Wind Warning | 12 | 3 | June 11, 2026 |
| Red Flag Warning | 9 | 1 | February 18, 2026 |
| Extreme Heat Watch | 8 | 1 | June 29, 2026 |
| Extreme Heat Warning | 8 | 2 | September 3, 2026 |
| High Wind Watch | 6 | 1 | March 13, 2026 |
| Freeze Watch | 6 | 1 | April 20, 2026 |
| Fire Weather Watch | 5 | 1 | February 18, 2026 |
| Snow Squall Warning | 3 | 1 | January 14, 2026 |
| Ice Storm Warning | 2 | 0 | February 12, 2019 |
| Extreme Cold Warning | 2 | 1 | January 23, 2026 |
| Dust Storm Warning | 2 | 0 | May 16, 2025 |
| Lake Effect Snow Warning | 1 | 0 | March 14, 2017 |
| Blizzard Warning | 1 | 0 | November 26, 2018 |
| Extreme Cold Watch | 1 | 1 | January 23, 2026 |
Tornado history in Cook County
87 tornadoes have been recorded in Cook County since 1950, killing 41 people and injuring 916. That ranks 4 of 102 counties in Illinois. The most recent was on March 19, 2025 (rated EF0).
Strongest tornadoes in Cook County
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| April 21, 1967 | F4 | Cook County | 15 mi | 200 yd | 33 | 500 |
| June 13, 1976 | F4 | Cook County | 3.3 mi | 1,760 yd | 2 | 23 |
| June 20, 2021 | EF3 | DuPage County | 17.6 mi | 600 yd | 0 | 11 |
| March 27, 1991 | F3 | Will County | 15 mi | 200 yd | 0 | 7 |
| November 12, 1965 | F2 | Grundy County | 35.9 mi | 120 yd | 2 | 90 |
Most recent tornadoes
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| March 19, 2025 | EF0 | Cook County | 0.3 mi | 50 yd | 0 | 0 |
| July 15, 2024 | EF0 | Cook County | 1.4 mi | 150 yd | 0 | 0 |
| July 15, 2024 | EF1 | Cook County | 3.1 mi | 400 yd | 0 | 0 |
| July 15, 2024 | EF1 | Cook County | 3.2 mi | 150 yd | 0 | 0 |
| July 15, 2024 | EF0 | Cook County | 0.4 mi | 125 yd | 0 | 0 |
About Cook County
- Population: 5,182,617 (2024 estimate)
- State: Illinois
- NOAA Weather Radio SAME code: 017031 (how to use it)
- Cities: Chicago