Alert archive / Pennsylvania / Mesoscale Discussions
Mesoscale Discussions in Pennsylvania, 2026
171 mesoscale discussions in 2026. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of mesoscale discussions reaches back to 2003.
Mesoscale Discussions by county
Each county as a circle sized by its count in 2026. Tap one for its archive.
- Mesoscale Discussions
- 171
- Busiest month
- July33 mesoscale discussions
- Busiest day
- June 6, 20266 mesoscale discussions
Over time
By month
The alerts
Every alert, in the order issued. Times are local, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 31, 11:26 PM EST | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Blair, Bradford and 33 more | 4 hr |
| Jan 1, 3:00 AM EST | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Lancaster and 8 more | 4 hr |
| Jan 11, 10:19 AM EST | Mesoscale Discussion | SPC | Armstrong, Bedford, Blair, Bradford, Cambria, Cameron and 17 more | 5 hr |
| Jan 17, 11:00 AM EST | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 9 more | 4 hr |
| Jan 17, 3:38 PM EST | Mesoscale Discussion | SPC | Cameron, Elk, Forest, McKean, Potter | 3 hr |
| Jan 19, 11:50 AM EST | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Blair, Bradford, Butler and 33 more | 4 hr |
| Jan 21, 10:14 PM EST | Mesoscale Discussion | SPC | Cameron, Clarion, Elk, Forest, Jefferson, McKean and 4 more | 3 hr |
| Jan 22, 8:52 AM EST | Mesoscale Discussion | SPC | Bradford, McKean, Potter, Susquehanna, Tioga, Warren | 4 hr |
| Jan 25, 6:01 AM EST | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Bedford, Berks, Blair and 38 more | 6 hr |
| Jan 25, 10:00 AM EST | Mesoscale Discussion | SPC | Beaver, Butler, Lawrence, Mercer | 3 hr |
| Jan 25, 11:55 AM EST | Mesoscale Discussion | SPC | Berks, Bradford, Cameron, Carbon, Centre, Clearfield and 23 more | 4 hr |
| Jan 25, 3:02 PM EST | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Bucks, Chester, Cumberland and 8 more | 4 hr |
| Jan 25, 4:02 PM EST | Mesoscale Discussion | SPC | Lackawanna, Monroe, Pike, Wayne | 4 hr |
| Feb 22, 4:58 PM EST | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 4 hr |
| Mar 3, 12:36 AM EST | Mesoscale Discussion | SPC | Adams, Armstrong, Bedford, Blair, Butler, Cambria and 18 more | 6 hr |
| Mar 3, 5:58 AM EST | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Bedford, Berks, Blair and 51 more | 5 hr |
| Mar 7, 12:57 PM EST | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 8 more | 2 hr |
| Mar 7, 3:55 PM EST | Mesoscale Discussion | SPC | Allegheny, Armstrong, Butler, Clarion, Fayette, Forest and 6 more | 2 hr |
| Mar 11, 10:10 AM EDT | Mesoscale Discussion | SPC | Allegheny, Beaver, Butler, Greene, Lawrence, Mercer and 1 more | 2 hr |
| Mar 11, 1:50 PM EDT | Mesoscale Discussion | SPC | Allegheny, Bedford, Cambria, Fayette, Fulton, Greene and 3 more | 85 min |
| Mar 11, 4:34 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Blair, Cambria, Cumberland, Dauphin and 13 more | 86 min |
| Mar 11, 6:47 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Chester, Cumberland, Dauphin and 7 more | 118 min |
| Mar 16, 10:57 AM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bradford, Carbon, Centre, Chester and 25 more | 93 min |
| Mar 16, 3:14 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Lehigh and 3 more | 91 min |
| Mar 16, 6:13 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Blair, Butler and 21 more | 4 hr |
| Mar 16, 10:55 PM EDT | Mesoscale Discussion | SPC | Bucks, Delaware, Monroe, Montgomery, Northampton, Philadelphia and 1 more | 2 hr |
| Mar 22, 3:02 PM EDT | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Bedford, Blair, Cambria and 19 more | 88 min |
| Mar 22, 6:36 PM EDT | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Beaver, Bedford, Blair and 27 more | 114 min |
| Mar 22, 9:07 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Fayette, Greene and 3 more | 83 min |
| Mar 26, 4:25 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 5 more | 95 min |
| Mar 26, 7:40 PM EDT | Mesoscale Discussion | SPC | Beaver, Butler, Crawford, Lawrence, Mercer, Venango | 95 min |
| Mar 26, 10:25 PM EDT | Mesoscale Discussion | SPC | Allegheny, Fayette, Greene, Washington, Westmoreland | 65 min |
| Mar 31, 1:49 PM EDT | Mesoscale Discussion | SPC | Crawford, McKean, Venango, Warren | 2 hr |
| Mar 31, 9:58 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Centre, Clarion and 5 more | 2 hr |
| Apr 1, 1:06 PM EDT | Mesoscale Discussion | SPC | Greene | 114 min |
| Apr 1, 3:50 PM EDT | Mesoscale Discussion | SPC | Adams | 115 min |
| Apr 1, 4:40 PM EDT | Mesoscale Discussion | SPC | Fayette, Greene | 2 hr |
| Apr 3, 4:15 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cameron, Clarion and 12 more | 2 hr |
| Apr 4, 1:46 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie | 2 hr |
| Apr 4, 4:39 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie | 2 hr |
| Apr 4, 6:55 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie | 95 min |
| Apr 14, 12:50 PM EDT | Mesoscale Discussion | SPC | Lackawanna, Susquehanna, Wayne | 2 hr |
| Apr 14, 2:03 PM EDT | Mesoscale Discussion | SPC | Armstrong, Beaver, Butler, Clarion, Crawford, Forest and 3 more | 87 min |
| Apr 14, 5:52 PM EDT | Mesoscale Discussion | SPC | Allegheny, Fayette, Greene, Somerset, Washington, Westmoreland | 83 min |
| Apr 15, 1:44 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie, Lawrence, Mercer, Venango | 3 hr |
| Apr 15, 4:53 PM EDT | Mesoscale Discussion | SPC | Cameron, Clarion, Elk, Forest, Jefferson, McKean and 3 more | 2 hr |
| Apr 16, 2:36 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 11 more | 84 min |
| Apr 16, 4:57 PM EDT | Mesoscale Discussion | SPC | Cameron, Clarion, Elk, Forest, Jefferson, McKean and 2 more | 63 min |
| Apr 18, 12:38 PM EDT | Mesoscale Discussion | SPC | Allegheny, Beaver, Butler, Greene, Lawrence, Mercer and 1 more | 3 hr |
| Apr 29, 1:48 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cambria, Clarion and 9 more | 117 min |
| May 9, 4:36 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie, Mercer, Warren | 84 min |
| May 9, 6:39 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie | 66 min |
| May 10, 3:10 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Chester, Delaware, Lancaster and 3 more | 3 hr |
| May 13, 11:56 AM EDT | Mesoscale Discussion | SPC | Cameron, Clarion, Clearfield, Clinton, Elk, Forest and 7 more | 3 hr |
| May 13, 12:41 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cambria, Fayette and 6 more | 3 hr |
| May 13, 5:54 PM EDT | Mesoscale Discussion | SPC | Bradford, Columbia, Dauphin, Juniata, Lackawanna, Lebanon and 11 more | 2 hr |
| May 19, 5:40 PM EDT | Mesoscale Discussion | SPC | Chester, Lancaster, York | 65 min |
| May 20, 7:50 AM EDT | Mesoscale Discussion | SPC | Greene, Washington | 115 min |
| May 20, 12:23 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Chester, Cumberland and 15 more | 97 min |
| May 20, 1:52 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Lehigh, Montgomery, Northampton and 1 more | 53 min |
| May 20, 3:09 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Carbon, Chester, Cumberland, Dauphin and 9 more | 96 min |
| May 20, 5:29 PM EDT | Mesoscale Discussion | SPC | Bucks, Delaware, Philadelphia | 61 min |
| Jun 6, 11:07 AM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cambria, Clarion and 11 more | 2 hr |
| Jun 6, 1:03 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Blair, Cambria, Cameron, Centre and 25 more | 87 min |
| Jun 6, 2:03 PM EDT | Mesoscale Discussion | SPC | Bradford, Lackawanna, Luzerne, Pike, Sullivan, Susquehanna and 2 more | 57 min |
| Jun 6, 3:57 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Blair, Cambria, Cameron, Centre and 20 more | 2 hr |
| Jun 6, 4:17 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Delaware, Lackawanna and 10 more | 118 min |
| Jun 6, 6:36 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Lehigh and 5 more | 114 min |
| Jun 6, 8:11 PM EDT | Mesoscale Discussion | SPC | Fayette, Greene, Washington | 94 min |
| Jun 11, 12:27 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Blair, Butler and 20 more | 2 hr |
| Jun 11, 3:02 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Bradford, Bucks, Carbon and 35 more | 118 min |
| Jun 11, 3:48 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Bedford, Blair, Butler, Cambria and 16 more | 117 min |
| Jun 11, 6:09 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Delaware, Lancaster and 6 more | 3 hr |
| Jun 12, 1:48 PM EDT | Mesoscale Discussion | SPC | Bucks, Carbon, Lackawanna, Lehigh, Luzerne, Monroe and 5 more | 117 min |
| Jun 12, 4:33 PM EDT | Mesoscale Discussion | SPC | Lackawanna, Monroe, Pike, Wayne | 87 min |
| Jun 14, 1:40 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 6 more | 5 min |
| Jun 14, 3:17 PM EDT | Mesoscale Discussion | SPC | Adams, Franklin, York | 118 min |
| Jun 14, 4:52 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cameron, Clarion and 16 more | 113 min |
| Jun 14, 5:54 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Bedford, Blair, Butler, Cambria and 17 more | 96 min |
| Jun 14, 6:22 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Columbia and 21 more | 113 min |
| Jun 14, 9:25 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Columbia and 24 more | 2 hr |
| Jun 18, 7:58 AM EDT | Mesoscale Discussion | SPC | Crawford, McKean, Warren | 2 hr |
| Jun 18, 9:31 AM EDT | Mesoscale Discussion | SPC | Bradford, McKean, Potter, Sullivan, Susquehanna, Tioga and 2 more | 119 min |
| Jun 22, 1:25 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Bucks, Chester, Cumberland and 17 more | 2 hr |
| Jun 22, 4:45 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 90 min |
| Jun 25, 3:10 PM EDT | Mesoscale Discussion | SPC | Crawford, Mercer | 2 hr |
| Jun 25, 5:52 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Blair, Butler and 16 more | 23 min |
| Jun 25, 8:43 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Blair, Butler, Cambria and 6 more | 62 min |
| Jun 30, 4:32 PM EDT | Mesoscale Discussion | SPC | Susquehanna | 118 min |
| Jul 1, 2:01 PM EDT | Mesoscale Discussion | SPC | Berks, Bradford, Bucks, Carbon, Columbia, Lackawanna and 14 more | 119 min |
| Jul 1, 6:40 PM EDT | Mesoscale Discussion | SPC | Bradford, Bucks, Carbon, Lackawanna, Lehigh, Luzerne and 7 more | 95 min |
| Jul 3, 12:25 PM EDT | Mesoscale Discussion | SPC | Armstrong, Bradford, Butler, Cameron, Centre, Clarion and 15 more | 2 hr |
| Jul 3, 4:34 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bradford, Bucks, Cameron, Carbon and 34 more | 116 min |
| Jul 3, 6:31 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Lehigh, Monroe, Montgomery and 4 more | 119 min |
| Jul 4, 1:36 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Blair, Butler and 25 more | 2 hr |
| Jul 4, 3:05 PM EDT | Mesoscale Discussion | SPC | Bradford, Cameron, Carbon, Centre, Clinton, Columbia and 18 more | 2 hr |
| Jul 4, 6:18 PM EDT | Mesoscale Discussion | SPC | Lackawanna, Pike, Wayne | 117 min |
| Jul 4, 6:47 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Columbia and 20 more | 118 min |
| Jul 4, 8:19 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Lancaster, Montgomery, Philadelphia | 116 min |
| Jul 5, 1:24 PM EDT | Mesoscale Discussion | SPC | Butler, Clarion, Crawford, Elk, Forest, Lawrence and 4 more | 3 hr |
| Jul 5, 6:00 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Chester, Cumberland, Dauphin and 16 more | 2 hr |
| Jul 5, 8:20 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Lebanon and 3 more | 115 min |
| Jul 6, 5:58 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Blair, Butler and 19 more | 2 hr |
| Jul 11, 2:56 PM EDT | Mesoscale Discussion | SPC | Berks, Chester, Dauphin, Delaware, Lancaster, Lebanon and 5 more | 2 hr |
| Jul 15, 3:55 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Columbia, Lackawanna, Lehigh and 13 more | 65 min |
| Jul 16, 3:59 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 2 hr |
| Jul 18, 11:01 AM EDT | Mesoscale Discussion | SPC | Monroe, Pike | 89 min |
| Jul 18, 12:18 PM EDT | Mesoscale Discussion | SPC | Armstrong, Beaver, Butler, Clarion, Crawford, Elk and 9 more | 117 min |
| Jul 18, 12:50 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Bucks, Chester, Cumberland and 10 more | 85 min |
| Jul 18, 3:28 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie, McKean, Warren | 92 min |
| Jul 18, 4:39 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 96 min |
| Jul 18, 6:47 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Clearfield and 7 more | 118 min |
| Jul 21, 12:15 PM EDT | Mesoscale Discussion | SPC | Greene | 2 hr |
| Jul 21, 1:23 PM EDT | Mesoscale Discussion | SPC | Berks, Bradford, Bucks, Carbon, Chester, Columbia and 20 more | 2 hr |
| Jul 21, 3:40 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Dauphin and 11 more | 95 min |
| Jul 21, 4:16 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie, Forest, Lawrence, Mercer, Venango and 1 more | 89 min |
| Jul 27, 2:11 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Columbia, Delaware and 15 more | 2 hr |
| Jul 27, 7:16 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Northampton, Philadelphia and 1 more | 119 min |
| Jul 28, 12:08 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Bucks, Cambria and 32 more | 2 hr |
| Jul 28, 2:30 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Bucks, Chester, Cumberland and 14 more | 2 hr |
| Jul 28, 4:53 PM EDT | Mesoscale Discussion | SPC | Berks, Chester, Delaware, Lancaster, Montgomery, Philadelphia and 1 more | 2 hr |
| Jul 28, 6:51 PM EDT | Mesoscale Discussion | SPC | Bucks, Delaware, Montgomery, Philadelphia | 54 min |
| Aug 3, 12:29 AM EDT | Mesoscale Discussion | SPC | Pike | 2 hr |
| Aug 6, 1:39 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Bradford, Bucks and 35 more | 2 hr |
| Aug 7, 12:50 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Delaware and 10 more | 2 hr |
| Aug 7, 4:04 PM EDT | Mesoscale Discussion | SPC | Bucks, Delaware, Montgomery, Northampton, Philadelphia | 116 min |
| Aug 8, 11:55 AM EDT | Mesoscale Discussion | SPC | Adams, Chester, Delaware, Lancaster, Philadelphia, York | 95 min |
| Aug 8, 1:11 PM EDT | Mesoscale Discussion | SPC | Lackawanna, Susquehanna, Wayne, Wyoming | 94 min |
| Aug 8, 5:54 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 10 more | 2 hr |
| Aug 10, 8:41 AM EDT | Mesoscale Discussion | SPC | Armstrong, Butler, Clarion, Crawford, Elk, Forest and 5 more | 2 hr |
| Aug 10, 9:29 AM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Dauphin, Delaware, Lancaster and 4 more | 91 min |
| Aug 10, 11:44 AM EDT | Mesoscale Discussion | SPC | Bradford, Cameron, Elk, McKean, Potter, Tioga | 2 hr |
| Aug 10, 1:38 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Bradford, Bucks and 37 more | 2 hr |
| Aug 10, 4:19 PM EDT | Mesoscale Discussion | SPC | Bucks, Delaware, Philadelphia | 116 min |
| Aug 11, 2:40 PM EDT | Mesoscale Discussion | SPC | Berks, Bradford, Bucks, Carbon, Chester, Columbia and 17 more | 2 hr |
| Aug 12, 1:10 PM EDT | Mesoscale Discussion | SPC | Bradford, McKean, Potter, Sullivan, Susquehanna, Tioga and 2 more | 2 hr |
| Aug 16, 11:56 AM EDT | Mesoscale Discussion | SPC | Allegheny, Beaver, Butler, Greene, Lawrence, Washington | 64 min |
| Aug 16, 2:28 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 6 more | 2 hr |
| Aug 16, 3:28 PM EDT | Mesoscale Discussion | SPC | Bedford, Fulton, Somerset | 2 hr |
| Aug 16, 7:00 PM EDT | Mesoscale Discussion | SPC | Adams, Cumberland, York | 60 min |
| Aug 20, 1:53 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Lancaster, Montgomery, Philadelphia and 1 more | 2 hr |
| Aug 20, 4:26 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 2 hr |
| Aug 22, 11:38 AM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cambria, Clarion and 16 more | 3 hr |
| Aug 22, 3:50 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 10 more | 115 min |
| Aug 22, 7:00 PM EDT | Mesoscale Discussion | SPC | Bedford, Blair, Cambria, Cameron, Centre, Clearfield and 11 more | 90 min |
| Aug 23, 12:03 PM EDT | Mesoscale Discussion | SPC | Bradford, Lackawanna, Luzerne, Lycoming, Pike, Potter and 5 more | 2 hr |
| Aug 23, 8:02 PM EDT | Mesoscale Discussion | SPC | Crawford | 88 min |
| Aug 27, 10:57 AM EDT | Mesoscale Discussion | SPC | Bucks, Delaware, Montgomery, Northampton, Philadelphia | 2 hr |
| Aug 27, 12:51 PM EDT | Mesoscale Discussion | SPC | Bradford, Lackawanna, Luzerne, Sullivan, Susquehanna, Wayne and 1 more | 114 min |
| Aug 27, 1:52 PM EDT | Mesoscale Discussion | SPC | Adams, Cumberland, Dauphin, Franklin, Fulton, Juniata and 2 more | 113 min |
| Aug 27, 2:29 PM EDT | Mesoscale Discussion | SPC | Delaware, Philadelphia | 2 hr |
| Aug 27, 7:06 PM EDT | Mesoscale Discussion | SPC | Lackawanna, Wayne | 84 min |
| Aug 27, 7:26 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Columbia, Cumberland, Dauphin, Lancaster and 8 more | 94 min |
| Sep 1, 3:13 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Columbia, Dauphin and 16 more | 2 hr |
| Sep 1, 6:00 PM EDT | Mesoscale Discussion | SPC | Armstrong, Bedford, Blair, Butler, Cambria, Clarion and 13 more | 90 min |
| Sep 1, 6:32 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Columbia, Dauphin and 12 more | 88 min |
| Sep 2, 6:04 AM EDT | Mesoscale Discussion | SPC | Crawford, Erie, Forest, Mercer, Venango, Warren | 116 min |
| Sep 2, 8:51 AM EDT | Mesoscale Discussion | SPC | Butler, Cameron, Clarion, Clearfield, Crawford, Elk and 9 more | 84 min |
| Sep 2, 11:09 AM EDT | Mesoscale Discussion | SPC | Adams, Cumberland, Franklin, Fulton, Perry, York | 66 min |
| Sep 2, 3:58 PM EDT | Mesoscale Discussion | SPC | Armstrong, Butler, Cameron, Centre, Clarion, Clearfield and 11 more | 92 min |
| Sep 2, 8:48 PM EDT | Mesoscale Discussion | SPC | Bradford, Cameron, Centre, Clarion, Clearfield, Clinton and 19 more | 87 min |
| Sep 3, 2:07 AM EDT | Mesoscale Discussion | SPC | Armstrong, Blair, Butler, Cambria, Cameron, Centre and 22 more | 113 min |
| Sep 3, 1:44 PM EDT | Mesoscale Discussion | SPC | Butler, Crawford, Erie, Lawrence, Mercer, Venango | 3 hr |
| Sep 3, 4:16 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Blair, Butler and 26 more | 119 min |
| Sep 3, 6:13 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Cambria, Fayette, Indiana, Somerset and 2 more | 92 min |
| Sep 3, 6:19 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Blair, Cambria, Cumberland, Fayette and 8 more | 116 min |
| Sep 3, 8:19 PM EDT | Mesoscale Discussion | SPC | Bedford, Franklin, Fulton | 56 min |
| Sep 9, 2:06 PM EDT | Mesoscale Discussion | SPC | Armstrong, Beaver, Butler, Cameron, Clarion, Crawford and 9 more | 84 min |
| Sep 9, 4:42 PM EDT | Mesoscale Discussion | SPC | Armstrong, Beaver, Butler, Cameron, Clarion, Crawford and 9 more | 93 min |
| Sep 12, 2:22 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 5 more | 113 min |
| Sep 13, 3:59 PM EDT | Mesoscale Discussion | SPC | Beaver, Butler, Cameron, Clarion, Crawford, Elk and 9 more | 2 hr |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Bucks County51
- Montgomery County50
- Butler County50
- Delaware County49
- Philadelphia County49
- Clarion County48
- Mercer County48
- Chester County47
- Armstrong County46
- Jefferson County45
- York County45
- Venango County45
- Lancaster County42
- Forest County42
- Crawford County42
- Lawrence County42
- Allegheny County41
- Berks County41
- McKean County39
- Beaver County38
- Lebanon County38
- Northampton County38
- Fayette County37
- Washington County37
- Westmoreland County37
- Adams County37
- Lehigh County37
- Elk County37
- Indiana County36
- Warren County35
- Dauphin County34
- Greene County34
- Bedford County33
- Clearfield County33
- Cumberland County33
- Schuylkill County33
- Pike County32
- Potter County32
- Cambria County31
- Fulton County31
27 more counties
- Somerset County31
- Cameron County31
- Franklin County30
- Huntingdon County30
- Monroe County30
- Centre County29
- Lackawanna County29
- Perry County29
- Carbon County29
- Blair County28
- Luzerne County28
- Northumberland County28
- Sullivan County28
- Columbia County27
- Mifflin County27
- Tioga County27
- Wayne County27
- Wyoming County27
- Juniata County26
- Montour County26
- Snyder County26
- Clinton County25
- Susquehanna County25
- Bradford County24
- Union County24
- Erie County21
- Lycoming County20
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Sources
National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.