Jefferson County weather alerts
There are no active weather alerts for Jefferson County, PA right now.
Since 2016 the National Weather Service has issued about 699 alerts that included Jefferson County, roughly 70 a year. The most common is the severe thunderstorm warning (196 from 2016 to 2025). The last tornado warning was issued on July 21, 2026. 16 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 Jefferson County at the moment. This page updates automatically when the National Weather Service issues one. Check neighboring Armstrong County, Elk County, Clarion County, Forest County.
Jefferson County alert history
Alert events that included Jefferson County or its forecast zones, from the NWS warning archive.
| Alert type | 2016–2025 | 2026 | Last issued |
|---|---|---|---|
| Severe Thunderstorm Warning | 196 | 38 | September 12, 2026 |
| Winter Weather Advisory | 92 | 7 | March 16, 2026 |
| Severe Thunderstorm Watch | 66 | 15 | September 9, 2026 |
| Wind Advisory | 35 | 2 | March 15, 2026 |
| Flood Watch | 32 | 8 | September 12, 2026 |
| Dense Fog Advisory | 31 | 7 | August 21, 2026 |
| Frost Advisory | 31 | 5 | October 6, 2026 |
| Freeze Warning | 28 | 6 | October 18, 2026 |
| Flood Advisory | 23 | 0 | August 7, 2024 |
| Flood Warning | 22 | 9 | October 11, 2026 |
| Flash Flood Warning | 22 | 17 | September 3, 2026 |
| Snow Squall Warning | 17 | 14 | March 17, 2026 |
| Cold Weather Advisory | 16 | 8 | February 9, 2026 |
| Freeze Watch | 15 | 4 | October 18, 2026 |
| Winter Storm Watch | 13 | 1 | January 25, 2026 |
| Winter Storm Warning | 12 | 1 | January 25, 2026 |
| Tornado Watch | 12 | 2 | June 14, 2026 |
| Tornado Warning | 12 | 5 | July 21, 2026 |
| High Wind Watch | 5 | 0 | December 23, 2022 |
| High Wind Warning | 3 | 1 | March 13, 2026 |
| Extreme Heat Watch | 3 | 0 | June 22, 2025 |
| Heat Advisory | 3 | 1 | June 30, 2026 |
| Red Flag Warning | 2 | 0 | April 12, 2023 |
| Extreme Cold Warning | 2 | 3 | February 7, 2026 |
| Ice Storm Warning | 2 | 0 | December 26, 2025 |
| Extreme Cold Watch | 2 | 2 | February 7, 2026 |
| Fire Weather Watch | 1 | 0 | April 12, 2023 |
| Lake Effect Snow Warning | 1 | 0 | December 4, 2024 |
| Extreme Heat Warning | 0 | 1 | June 30, 2026 |
Tornado history in Jefferson County
16 tornadoes have been recorded in Jefferson County since 1950, killing 2 people and injuring 14. That ranks 25 of 67 counties in Pennsylvania. The most recent was on October 16, 2021 (rated EF1).
Strongest tornadoes in Jefferson County
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| July 11, 1976 | F2 | Jefferson County | 28.7 mi | 33 yd | 1 | 7 |
| July 19, 1996 | F2 | Jefferson County | 27.4 mi | 200 yd | 0 | 6 |
| July 19, 1996 | F2 | Clarion County | 10 mi | 100 yd | 0 | 0 |
| October 2, 2018 | EF2 | Jefferson County | 4.1 mi | 200 yd | 0 | 0 |
| October 16, 2021 | EF1 | Jefferson County | 1.2 mi | 260 yd | 1 | 1 |
Most recent tornadoes
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| October 16, 2021 | EF1 | Jefferson County | 1.2 mi | 260 yd | 1 | 1 |
| October 2, 2018 | EF2 | Jefferson County | 4.1 mi | 200 yd | 0 | 0 |
| October 2, 2018 | EF0 | Jefferson County | 4.8 mi | 50 yd | 0 | 0 |
| August 21, 2018 | EF1 | Jefferson County | 2.4 mi | 300 yd | 0 | 0 |
| August 21, 2014 | EF0 | Jefferson County | 5.4 mi | 50 yd | 0 | 0 |
About Jefferson County
- Population: 43,367 (2024 estimate)
- State: Pennsylvania
- NOAA Weather Radio SAME code: 042065 (how to use it)