National Weather ServicePennsylvaniaExtreme Heat WarningArchive to October 1, 2026
Extreme Heat Warnings in Pennsylvania
The National Weather Service issued 5 extreme heat warnings for Pennsylvania in 2025 and 4 a year on average in 2008-2025; in 2021-2025 it had the 28th most of any state. 2026 through September: 5, 34% above the average of 4 for those months in 2008-2025. Philadelphia was covered most often (46 times since 2008).
How many extreme heat warnings does Pennsylvania get?
Every extreme heat warning that covered part of Pennsylvania. 2026 is an outline: the year is not over.
The numbers
| Year | Count |
|---|---|
| 2026 (through September) | 5 |
| 2025 | 5 |
| 2024 | 8 |
| 2023 | 1 |
| 2022 | 2 |
| 2021 | 4 |
| 2020 | 1 |
| 2019 | 5 |
| 2018 | 2 |
| 2017 | 2 |
| 2016 | 6 |
| 2015 | 2 |
| 2014 | 0 |
| 2013 | 2 |
| 2012 | 8 |
| 2011 | 10 |
| 2010 | 6 |
| 2009 | 1 |
| 2008 | 2 |
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
When in the year does Pennsylvania get them?
Sum of 2008-2025; the busiest month is labelled.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
Where in Pennsylvania?
| County or forecast zone | Since 2008 | Since 2023 | Last issued |
|---|---|---|---|
| Philadelphia | 46 | 11 | July 15, 2026 |
| Delaware | 46 | 11 | July 15, 2026 |
| Lower Bucks | 29 | 11 | July 15, 2026 |
| Eastern Montgomery | 29 | 11 | July 15, 2026 |
| Eastern Chester | 24 | 6 | July 1, 2026 |
| Montgomery | 17 | 0 | July 26, 2012 |
| Chester | 17 | 0 | July 26, 2012 |
| Bucks | 17 | 0 | July 26, 2012 |
| York | 14 | 3 | July 1, 2026 |
| Dauphin | 14 | 3 | July 1, 2026 |
| Lebanon | 13 | 3 | July 1, 2026 |
| Lancaster | 13 | 3 | July 1, 2026 |
The NWS issues these products for counties or forecast zones; a zone can be part of a county or a mountain range.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
The latest extreme heat warnings for Pennsylvania in AreaZine's record
NWS Mount HollyWarningJuly 14, 2026
Extreme Heat Warning: New Castle, Mercer, Gloucester and 6 more, DE and NJ
Expired 8:00 p.m. EDT, July 15, 2026
NWS State CollegeWarningJuly 4, 2026
Extreme Heat Warning: Fulton, Franklin, Perry and 1 more, PA
Expired 8:00 p.m. EDT, July 4, 2026
NWS BinghamtonWarningJuly 2, 2026
Extreme Heat Warning: Northern Oneida, Yates, Seneca and 23 more, NY and PA
Expired 8:00 p.m. EDT, July 3, 2026
NWS PittsburghWarningJune 30, 2026
Extreme Heat Warning: Mercer, Venango, Forest and 19 more, PA and WV
Expired 10:00 p.m. EDT, July 3, 2026
NWS Mount HollyWarningJune 30, 2026
Extreme Heat Warning: New Castle, Mercer, Salem and 8 more, DE and NJ
Expired 8:00 p.m. EDT, July 4, 2026
This list is AreaZine's record of the NWS alert feed, kept since April 6, 2026; the counts above come from the complete IEM archive.
Source: National Weather Service alerts (api.weather.gov).
What is an extreme heat warning?
An extreme heat warning means dangerous heat is expected, measured by heat index or temperature thresholds each office sets. It replaced the excessive heat warning in 2025. A warning means the hazard is happening, about to happen, or very likely: act now to protect people and property. AreaZine's counts include the excessive heat warnings issued before the change. The national record · Every warning type in Pennsylvania.