Grundy County weather alerts
There are no active weather alerts for Grundy County, IL right now.
Since 2016 the National Weather Service has issued about 905 alerts that included Grundy County, roughly 91 a year. The most common is the flood advisory (147 from 2016 to 2025). The last tornado warning was issued on August 11, 2026. 26 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 Grundy County at the moment. This page updates automatically when the National Weather Service issues one. Check neighboring Kendall County, LaSalle County, Kankakee County, Livingston County.
Grundy County alert history
Alert events that included Grundy County or its forecast zones, from the NWS warning archive.
| Alert type | 2016–2025 | 2026 | Last issued |
|---|---|---|---|
| Flood Advisory | 147 | 14 | October 2, 2026 |
| Dense Fog Advisory | 97 | 8 | September 28, 2026 |
| Severe Thunderstorm Warning | 94 | 22 | August 12, 2026 |
| Winter Weather Advisory | 82 | 2 | March 16, 2026 |
| Severe Thunderstorm Watch | 72 | 15 | August 21, 2026 |
| Wind Advisory | 72 | 6 | April 27, 2026 |
| Flood Warning | 51 | 2 | August 10, 2026 |
| Flood Watch | 51 | 16 | October 1, 2026 |
| Tornado Watch | 29 | 6 | June 17, 2026 |
| Cold Weather Advisory | 28 | 3 | January 26, 2026 |
| Heat Advisory | 24 | 4 | September 4, 2026 |
| Flash Flood Warning | 21 | 3 | August 12, 2026 |
| Frost Advisory | 20 | 3 | May 7, 2026 |
| Freeze Warning | 17 | 1 | April 20, 2026 |
| Winter Storm Watch | 16 | 0 | November 29, 2025 |
| Winter Storm Warning | 14 | 0 | November 29, 2025 |
| Red Flag Warning | 11 | 1 | February 18, 2026 |
| High Wind Warning | 9 | 2 | June 11, 2026 |
| Extreme Heat Warning | 7 | 2 | July 27, 2026 |
| Tornado Warning | 7 | 6 | August 11, 2026 |
| Extreme Heat Watch | 6 | 0 | July 23, 2025 |
| Fire Weather Watch | 6 | 1 | February 18, 2026 |
| Freeze Watch | 6 | 1 | April 20, 2026 |
| High Wind Watch | 5 | 0 | March 15, 2025 |
| Extreme Cold Warning | 5 | 1 | January 23, 2026 |
| Ice Storm Warning | 3 | 0 | January 1, 2021 |
| Dust Storm Warning | 2 | 0 | May 16, 2025 |
| Blizzard Warning | 1 | 0 | November 26, 2018 |
| Extreme Cold Watch | 1 | 1 | January 23, 2026 |
| Snow Squall Warning | 1 | 0 | February 19, 2022 |
Tornado history in Grundy County
26 tornadoes have been recorded in Grundy County since 1950, killing 2 people and injuring 106. That ranks 58 of 102 counties in Illinois. The most recent was on July 15, 2024 (rated EF2).
Strongest tornadoes in Grundy County
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| July 17, 1972 | F3 | Marshall County | 81.5 mi | 200 yd | 0 | 0 |
| June 22, 2015 | EF3 | Grundy County | 16.3 mi | 1,320 yd | 0 | 7 |
| November 12, 1965 | F2 | Grundy County | 35.9 mi | 120 yd | 2 | 90 |
| July 15, 2024 | EF2 | Grundy County | 34.6 mi | 325 yd | 0 | 2 |
| November 12, 1965 | F2 | LaSalle County | 32.1 mi | 17 yd | 0 | 0 |
Most recent tornadoes
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| July 15, 2024 | EF2 | Grundy County | 34.6 mi | 325 yd | 0 | 2 |
| July 28, 2023 | EF0 | Grundy County | 5.1 mi | 250 yd | 0 | 0 |
| May 23, 2020 | EF0 | Grundy County | 6.3 mi | 100 yd | 0 | 1 |
| May 17, 2020 | ? | Grundy County | 0.5 mi | 25 yd | 0 | 0 |
| February 28, 2017 | EF0 | Grundy County | 1.2 mi | 200 yd | 0 | 0 |
About Grundy County
- Population: 53,835 (2024 estimate)
- State: Illinois
- NOAA Weather Radio SAME code: 017063 (how to use it)