Johnson County weather alerts
There are no active weather alerts for Johnson County, IA right now.
Since 2016 the National Weather Service has issued about 957 alerts that included Johnson County, roughly 96 a year. The most common is the severe thunderstorm warning (161 from 2016 to 2025). The last tornado warning was issued on September 9, 2026. 45 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 Johnson County at the moment. This page updates automatically when the National Weather Service issues one. Check neighboring Cedar County, Washington County, Linn County, Muscatine County.
Johnson County alert history
Alert events that included Johnson County or its forecast zones, from the NWS warning archive.
| Alert type | 2016–2025 | 2026 | Last issued |
|---|---|---|---|
| Severe Thunderstorm Warning | 161 | 41 | September 20, 2026 |
| Dense Fog Advisory | 102 | 6 | September 17, 2026 |
| Winter Weather Advisory | 97 | 3 | March 16, 2026 |
| Wind Advisory | 69 | 3 | March 12, 2026 |
| Flood Warning | 64 | 13 | October 2, 2026 |
| Severe Thunderstorm Watch | 64 | 14 | August 13, 2026 |
| Heat Advisory | 48 | 2 | August 31, 2026 |
| Flood Watch | 44 | 9 | September 30, 2026 |
| Cold Weather Advisory | 43 | 3 | January 26, 2026 |
| Tornado Warning | 34 | 6 | September 9, 2026 |
| Tornado Watch | 30 | 9 | July 20, 2026 |
| Flash Flood Warning | 29 | 5 | September 20, 2026 |
| Freeze Warning | 27 | 2 | October 17, 2026 |
| Winter Storm Watch | 24 | 1 | March 16, 2026 |
| Winter Storm Warning | 23 | 0 | December 18, 2025 |
| Frost Advisory | 21 | 2 | May 7, 2026 |
| Red Flag Warning | 15 | 2 | March 28, 2026 |
| Extreme Heat Warning | 12 | 3 | September 2, 2026 |
| Extreme Cold Warning | 10 | 1 | January 23, 2026 |
| Extreme Heat Watch | 8 | 2 | July 27, 2026 |
| Freeze Watch | 8 | 1 | October 17, 2026 |
| High Wind Warning | 6 | 3 | March 15, 2026 |
| High Wind Watch | 4 | 1 | March 15, 2026 |
| Extreme Cold Watch | 4 | 1 | January 23, 2026 |
| Fire Weather Watch | 4 | 1 | February 18, 2026 |
| Snow Squall Warning | 3 | 0 | February 19, 2022 |
| Blizzard Warning | 2 | 1 | March 15, 2026 |
| Ice Storm Warning | 1 | 0 | December 14, 2024 |
Tornado history in Johnson County
45 tornadoes have been recorded in Johnson County since 1950, killing 4 people and injuring 92. That ranks 23 of 99 counties in Iowa. The most recent was on May 24, 2024 (rated EF0).
Strongest tornadoes in Johnson County
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| March 31, 2023 | EF4 | Keokuk County | 19.9 mi | 700 yd | 0 | 3 |
| May 15, 1998 | F3 | Washington County | 47 mi | 400 yd | 0 | 47 |
| May 22, 1962 | F2 | Johnson County | 4.1 mi | 800 yd | 1 | 0 |
| May 8, 1988 | F2 | Poweshiek County | 59 mi | 60 yd | 0 | 0 |
| May 8, 1988 | F2 | Keokuk County | 36 mi | 60 yd | 0 | 0 |
Most recent tornadoes
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| May 24, 2024 | EF0 | Johnson County | 0.1 mi | 50 yd | 0 | 0 |
| May 24, 2024 | EF1 | Johnson County | 15 mi | 75 yd | 0 | 0 |
| May 24, 2024 | EF1 | Washington County | 22.5 mi | 150 yd | 0 | 0 |
| May 24, 2024 | EF1 | Washington County | 18.3 mi | 100 yd | 0 | 0 |
| March 31, 2023 | EF2 | Johnson County | 9 mi | 75 yd | 0 | 0 |
About Johnson County
- Population: 160,080 (2024 estimate)
- State: Iowa
- NOAA Weather Radio SAME code: 019103 (how to use it)