Mercer County weather alerts
There are no active weather alerts for Mercer County, PA right now.
Since 2016 the National Weather Service has issued about 695 alerts that included Mercer County, roughly 70 a year. The most common is the severe thunderstorm warning (223 from 2016 to 2025). The last tornado warning was issued on September 3, 2026. 22 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 Mercer County at the moment. This page updates automatically when the National Weather Service issues one. Check neighboring Venango County, Lawrence County, Crawford County, Trumbull County.
Mercer County alert history
Alert events that included Mercer County or its forecast zones, from the NWS warning archive.
| Alert type | 2016–2025 | 2026 | Last issued |
|---|---|---|---|
| Severe Thunderstorm Warning | 223 | 45 | September 13, 2026 |
| Winter Weather Advisory | 88 | 4 | March 16, 2026 |
| Severe Thunderstorm Watch | 57 | 14 | September 9, 2026 |
| Flood Advisory | 38 | 0 | August 6, 2024 |
| Wind Advisory | 32 | 2 | March 15, 2026 |
| Dense Fog Advisory | 31 | 5 | May 25, 2026 |
| Flash Flood Warning | 29 | 8 | September 13, 2026 |
| Flood Watch | 27 | 6 | September 12, 2026 |
| Frost Advisory | 22 | 2 | May 11, 2026 |
| Freeze Warning | 22 | 6 | October 18, 2026 |
| Tornado Warning | 15 | 2 | September 3, 2026 |
| Flood Warning | 14 | 2 | April 1, 2026 |
| Freeze Watch | 13 | 4 | October 18, 2026 |
| Cold Weather Advisory | 13 | 7 | February 9, 2026 |
| Snow Squall Warning | 13 | 12 | March 17, 2026 |
| Winter Storm Warning | 10 | 1 | January 25, 2026 |
| Tornado Watch | 10 | 2 | March 26, 2026 |
| Winter Storm Watch | 9 | 1 | January 25, 2026 |
| Heat Advisory | 6 | 2 | July 15, 2026 |
| Lake Effect Snow Warning | 5 | 0 | December 13, 2025 |
| High Wind Watch | 5 | 0 | December 23, 2022 |
| High Wind Warning | 4 | 1 | March 13, 2026 |
| Extreme Heat Watch | 3 | 0 | June 22, 2025 |
| Extreme Cold Warning | 2 | 2 | February 7, 2026 |
| Extreme Cold Watch | 2 | 2 | February 7, 2026 |
| Fire Weather Watch | 1 | 0 | April 12, 2023 |
| Red Flag Warning | 1 | 0 | April 12, 2023 |
| Extreme Heat Warning | 0 | 1 | June 30, 2026 |
Tornado history in Mercer County
22 tornadoes have been recorded in Mercer County since 1950, killing 1 people and injuring 31. That ranks 11 of 67 counties in Pennsylvania. The most recent was on August 6, 2024 (rated unknown).
Strongest tornadoes in Mercer County
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| May 2, 1972 | F3 | Mercer County | 7.9 mi | 33 yd | 0 | 3 |
| November 10, 2002 | F2 | Mercer County | 7 mi | 500 yd | 1 | 19 |
| October 3, 1986 | F2 | Mercer County | 9 mi | 123 yd | 0 | 0 |
| June 1, 1954 | F2 | Mercer County | 0.1 mi | 10 yd | 0 | 3 |
| September 30, 1954 | F2 | Mercer County | 0.1 mi | 10 yd | 0 | 0 |
Most recent tornadoes
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| August 6, 2024 | ? | Mercer County | 0 mi | 20 yd | 0 | 0 |
| September 22, 2021 | EF1 | Mercer County | 0.3 mi | 90 yd | 0 | 0 |
| June 16, 2019 | EF1 | Mercer County | 1.1 mi | 150 yd | 0 | 0 |
| January 8, 2019 | EF1 | Mercer County | 2.8 mi | 400 yd | 0 | 0 |
| May 31, 2015 | EF0 | Mercer County | 1.1 mi | 250 yd | 0 | 0 |
About Mercer County
- Population: 108,140 (2024 estimate)
- State: Pennsylvania
- NOAA Weather Radio SAME code: 042085 (how to use it)