Alert archive / Pennsylvania / Mesoscale Discussions
Mesoscale Discussions in Pennsylvania, 2020
121 mesoscale discussions in 2020. 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 2020. Tap one for its archive.
- Mesoscale Discussions
- 121
- Busiest month
- August26 mesoscale discussions
- Busiest day
- June 3, 20207 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 |
|---|---|---|---|---|
| Jan 7, 12:29 PM EST | Mesoscale Discussion | SPC | Adams, Cumberland, Franklin, Fulton, Huntingdon, Juniata and 2 more | 2 hr |
| Jan 8, 6:37 AM EST | Mesoscale Discussion | SPC | Bradford, Susquehanna, Tioga | 6 hr |
| Feb 6, 7:48 PM EST | Mesoscale Discussion | SPC | Crawford, Erie | 4 hr |
| Feb 7, 5:32 AM EST | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cameron, Clarion and 12 more | 3 hr |
| Feb 7, 9:50 AM EST | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 85 min |
| Feb 26, 2:49 PM EST | Mesoscale Discussion | SPC | Bedford, Blair, Cambria, Centre, Franklin, Fulton and 3 more | 116 min |
| Mar 3, 1:22 PM EST | Mesoscale Discussion | SPC | Allegheny, Bedford, Cambria, Fayette, Fulton, Greene and 3 more | 113 min |
| Mar 3, 4:27 PM EST | Mesoscale Discussion | SPC | Adams, Armstrong, Bedford, Blair, Cambria, Cameron and 20 more | 2 hr |
| Mar 3, 6:50 PM EST | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Columbia, Dauphin and 17 more | 2 hr |
| Mar 3, 10:52 PM EST | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Columbia and 21 more | 113 min |
| Mar 20, 12:40 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 11 more | 2 hr |
| Mar 28, 10:32 AM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Indiana and 4 more | 88 min |
| Mar 28, 4:03 PM EDT | Mesoscale Discussion | SPC | Allegheny, Beaver, Butler, Greene, Lawrence, Washington and 1 more | 87 min |
| Mar 28, 5:51 PM EDT | Mesoscale Discussion | SPC | Bedford, Blair, Cambria, Franklin, Fulton, Huntingdon and 1 more | 84 min |
| Mar 29, 10:58 AM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Butler, Clarion, Elk, Forest and 5 more | 2 hr |
| Mar 29, 2:21 PM EDT | Mesoscale Discussion | SPC | McKean, Potter | 84 min |
| Apr 7, 4:57 PM EDT | Mesoscale Discussion | SPC | Greene | 63 min |
| Apr 7, 10:04 PM EDT | Mesoscale Discussion | SPC | Beaver, Crawford, Lawrence, Mercer, Venango | 86 min |
| Apr 7, 10:54 PM EDT | Mesoscale Discussion | SPC | Armstrong, Blair, Butler, Cambria, Cameron, Centre and 19 more | 2 hr |
| Apr 8, 1:52 AM EDT | Mesoscale Discussion | SPC | Bedford, Cambria, Fayette, Fulton, Greene, Somerset and 2 more | 83 min |
| Apr 9, 11:09 AM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Lehigh and 3 more | 66 min |
| Apr 13, 10:34 AM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Chester, Cumberland, Dauphin and 17 more | 86 min |
| Apr 13, 1:20 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Blair, Bucks, Carbon, Centre and 25 more | 85 min |
| Apr 13, 2:42 PM EDT | Mesoscale Discussion | SPC | Bradford, Lackawanna, Pike, Sullivan, Susquehanna, Wayne and 1 more | 93 min |
| Apr 17, 6:55 PM EDT | Mesoscale Discussion | SPC | Bradford, Cameron, Centre, Clearfield, Clinton, Elk and 8 more | 4 hr |
| Apr 21, 12:23 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Lehigh, Montgomery, Northampton and 1 more | 2 hr |
| May 15, 1:52 PM EDT | Mesoscale Discussion | SPC | Butler, Cameron, Clarion, Crawford, Elk, Erie and 8 more | 83 min |
| May 15, 2:59 PM EDT | Mesoscale Discussion | SPC | Susquehanna, Wayne, Wyoming | 91 min |
| May 15, 4:58 PM EDT | Mesoscale Discussion | SPC | Susquehanna | 92 min |
| May 15, 7:47 PM EDT | Mesoscale Discussion | SPC | Bradford, Cameron, Clinton, Elk, Forest, Jefferson and 8 more | 58 min |
| May 29, 10:47 AM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cameron, Clarion and 14 more | 118 min |
| May 29, 12:27 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Columbia and 27 more | 63 min |
| May 29, 3:03 PM EDT | Mesoscale Discussion | SPC | Berks, Carbon, Lancaster, Lehigh, Monroe, Northampton and 2 more | 87 min |
| May 29, 4:54 PM EDT | Mesoscale Discussion | SPC | Cameron, Clearfield, Clinton, Elk, Jefferson, McKean and 2 more | 2 hr |
| May 29, 8:01 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bradford, Bucks, Carbon, Chester and 29 more | 119 min |
| Jun 2, 9:26 PM EDT | Mesoscale Discussion | SPC | McKean, Potter, Tioga, Warren | 3 hr |
| Jun 3, 5:12 AM EDT | Mesoscale Discussion | SPC | Crawford, Erie, Forest, McKean, Warren | 2 hr |
| Jun 3, 8:32 AM EDT | Mesoscale Discussion | SPC | Adams, Armstrong, Berks, Blair, Bradford, Butler and 38 more | 118 min |
| Jun 3, 11:34 AM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Cumberland and 11 more | 86 min |
| Jun 3, 3:10 PM EDT | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Beaver, Bedford, Blair and 32 more | 2 hr |
| Jun 3, 6:58 PM EDT | Mesoscale Discussion | SPC | Lackawanna, Monroe, Northampton, Pike, Susquehanna, Wayne and 1 more | 92 min |
| Jun 3, 7:44 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Cumberland, Dauphin, Delaware and 6 more | 91 min |
| Jun 4, 12:45 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 5 more | 90 min |
| Jun 4, 2:02 PM EDT | Mesoscale Discussion | SPC | Adams, Cumberland, Franklin, Fulton, Perry, York | 118 min |
| Jun 4, 2:14 PM EDT | Mesoscale Discussion | SPC | Beaver, Lawrence, Washington | 61 min |
| Jun 4, 4:00 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Greene and 4 more | 90 min |
| Jun 4, 4:41 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Blair, Cambria, Centre, Clinton and 16 more | 94 min |
| Jun 4, 6:44 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Centre, Chester and 19 more | 91 min |
| Jun 10, 1:39 PM EDT | Mesoscale Discussion | SPC | Bedford, Blair, Bradford, Centre, Clinton, Columbia and 15 more | 2 hr |
| Jun 10, 6:35 PM EDT | Mesoscale Discussion | SPC | Beaver, Crawford, Erie, Lawrence, Mercer, Washington | 85 min |
| Jun 10, 9:03 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 8 more | 57 min |
| Jun 22, 1:58 PM EDT | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Beaver, Bedford, Blair and 36 more | 3 hr |
| Jun 25, 1:48 PM EDT | Mesoscale Discussion | SPC | Adams | 117 min |
| Jun 27, 12:35 AM EDT | Mesoscale Discussion | SPC | Crawford, Erie, Mercer, Venango | 115 min |
| Jun 27, 2:48 AM EDT | Mesoscale Discussion | SPC | Crawford, Mercer | 57 min |
| Jun 27, 12:34 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Columbia, Dauphin, Juniata and 12 more | 2 hr |
| Jun 28, 12:37 PM EDT | Mesoscale Discussion | SPC | Lackawanna, Monroe, Pike, Susquehanna, Wayne, Wyoming | 113 min |
| Jun 28, 4:08 PM EDT | Mesoscale Discussion | SPC | Pike | 2 hr |
| Jul 6, 12:33 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Lehigh and 4 more | 3 hr |
| Jul 6, 4:33 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Cumberland and 12 more | 117 min |
| Jul 6, 6:25 PM EDT | Mesoscale Discussion | SPC | Chester, Delaware, Lancaster, Montgomery, Philadelphia | 2 hr |
| Jul 6, 8:39 PM EDT | Mesoscale Discussion | SPC | Chester, Delaware, Lancaster, Lebanon, Montgomery, York | 2 hr |
| Jul 8, 1:29 PM EDT | Mesoscale Discussion | SPC | Bradford, Susquehanna, Tioga, Wayne, Wyoming | 91 min |
| Jul 10, 4:11 PM EDT | Mesoscale Discussion | SPC | Beaver, Butler, Crawford, Erie, Greene, Lawrence and 2 more | 94 min |
| Jul 11, 2:06 PM EDT | Mesoscale Discussion | SPC | Berks, Bradford, Bucks, Carbon, Chester, Columbia and 14 more | 84 min |
| Jul 16, 12:18 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Clearfield and 15 more | 117 min |
| Jul 16, 3:51 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cameron, Clarion and 17 more | 84 min |
| Jul 16, 7:51 PM EDT | Mesoscale Discussion | SPC | Cameron, Clarion, Clearfield, Elk, Forest, Jefferson and 3 more | 54 min |
| Jul 19, 3:11 PM EDT | Mesoscale Discussion | SPC | Crawford, Forest, McKean, Potter, Warren | 94 min |
| Jul 19, 5:52 PM EDT | Mesoscale Discussion | SPC | Bradford, Carbon, Clinton, Columbia, Lackawanna, Luzerne and 13 more | 83 min |
| Jul 19, 6:54 PM EDT | Mesoscale Discussion | SPC | Beaver, Butler, Clarion, Crawford, Forest, Lawrence and 3 more | 66 min |
| Jul 21, 2:01 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Blair, Cumberland, Dauphin, Franklin and 5 more | 59 min |
| Jul 22, 10:48 AM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Cambria, Chester and 15 more | 117 min |
| Jul 22, 1:45 PM EDT | Mesoscale Discussion | SPC | Bucks, Carbon, Lackawanna, Lehigh, Monroe, Montgomery and 4 more | 2 hr |
| Jul 22, 4:55 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Delaware, Lancaster and 5 more | 95 min |
| Jul 22, 7:01 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 119 min |
| Jul 23, 12:05 PM EDT | Mesoscale Discussion | SPC | Bradford, Clinton, Columbia, Lackawanna, Luzerne, Lycoming and 7 more | 115 min |
| Jul 23, 4:28 PM EDT | Mesoscale Discussion | SPC | Carbon, Lackawanna, Luzerne, Monroe, Northampton, Pike and 2 more | 2 hr |
| Jul 23, 6:48 PM EDT | Mesoscale Discussion | SPC | Carbon, Columbia, Lackawanna, Lehigh, Luzerne, Monroe and 9 more | 57 min |
| Jul 29, 1:36 PM EDT | Mesoscale Discussion | SPC | Cameron, Clarion, Crawford, Elk, Erie, Forest and 7 more | 84 min |
| Jul 30, 1:20 PM EDT | Mesoscale Discussion | SPC | Berks, Bradford, Bucks, Carbon, Columbia, Lackawanna and 15 more | 115 min |
| Aug 1, 2:19 PM EDT | Mesoscale Discussion | SPC | Greene, Washington | 56 min |
| Aug 1, 4:00 PM EDT | Mesoscale Discussion | SPC | Franklin, Fulton | 2 hr |
| Aug 1, 7:05 PM EDT | Mesoscale Discussion | SPC | Adams, Franklin, Fulton | 115 min |
| Aug 2, 6:53 AM EDT | Mesoscale Discussion | SPC | Lehigh, Northampton | 3 hr |
| Aug 2, 2:00 PM EDT | Mesoscale Discussion | SPC | Carbon, Columbia, Lackawanna, Luzerne, Monroe, Northampton and 6 more | 2 hr |
| Aug 2, 6:45 PM EDT | Mesoscale Discussion | SPC | Monroe, Pike, Wayne | 2 hr |
| Aug 4, 6:45 AM EDT | Mesoscale Discussion | SPC | Bucks, Delaware, Montgomery, Philadelphia | 3 hr |
| Aug 4, 8:59 AM EDT | Mesoscale Discussion | SPC | Philadelphia | 91 min |
| Aug 4, 11:13 AM EDT | Mesoscale Discussion | SPC | Bucks, Philadelphia | 92 min |
| Aug 7, 1:30 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Chester, Cumberland, Dauphin, Delaware and 11 more | 3 hr |
| Aug 12, 1:15 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Lancaster, Montgomery, Philadelphia and 1 more | 2 hr |
| Aug 23, 3:57 PM EDT | Mesoscale Discussion | SPC | Adams, Cumberland, Dauphin, Franklin, Lancaster, Lebanon and 2 more | 2 hr |
| Aug 24, 12:44 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Bradford, Carbon, Centre and 31 more | 2 hr |
| Aug 25, 12:02 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bradford, Butler, Cambria and 21 more | 118 min |
| Aug 25, 3:10 PM EDT | Mesoscale Discussion | SPC | Adams, Bucks, Chester, Delaware, Lancaster, Montgomery and 2 more | 95 min |
| Aug 25, 4:35 PM EDT | Mesoscale Discussion | SPC | Bedford, Fayette, Greene, Somerset, Washington, Westmoreland | 85 min |
| Aug 25, 6:11 PM EDT | Mesoscale Discussion | SPC | Carbon, Lehigh, Luzerne, Monroe, Northampton, Pike | 2 hr |
| Aug 27, 12:38 PM EDT | Mesoscale Discussion | SPC | Susquehanna, Wayne | 3 hr |
| Aug 27, 2:14 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Blair, Cambria, Cumberland, Fayette and 6 more | 2 hr |
| Aug 27, 4:34 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Blair, Butler, Cambria and 9 more | 86 min |
| Aug 27, 6:35 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Bucks, Chester and 24 more | 115 min |
| Aug 28, 9:55 AM EDT | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Bedford, Blair, Butler and 20 more | 3 hr |
| Aug 28, 1:32 PM EDT | Mesoscale Discussion | SPC | Beaver | 88 min |
| Aug 28, 3:50 PM EDT | Mesoscale Discussion | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 85 min |
| Aug 29, 3:56 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Columbia, Cumberland and 21 more | 2 hr |
| Aug 29, 6:45 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Lehigh, Monroe, Northampton, Pike | 2 hr |
| Sep 2, 3:37 PM EDT | Mesoscale Discussion | SPC | Adams, Chester, Cumberland, Dauphin, Franklin, Lancaster and 2 more | 53 min |
| Sep 2, 8:20 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Montgomery and 1 more | 115 min |
| Sep 3, 3:06 PM EDT | Mesoscale Discussion | SPC | Adams, Chester, Cumberland, Delaware, Franklin, Fulton and 3 more | 114 min |
| Nov 15, 11:33 AM EST | Mesoscale Discussion | SPC | Crawford, Erie, Lawrence, Mercer, Venango | 57 min |
| Nov 15, 1:16 PM EST | Mesoscale Discussion | SPC | Allegheny, Armstrong, Clarion, Elk, Forest, Indiana and 5 more | 89 min |
| Nov 15, 3:33 PM EST | Mesoscale Discussion | SPC | Adams, Berks, Bucks, Carbon, Chester, Columbia and 23 more | 2 hr |
| Nov 15, 6:52 PM EST | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Delaware, Lancaster and 7 more | 113 min |
| Nov 30, 12:26 PM EST | Mesoscale Discussion | SPC | Chester, Delaware, Montgomery, Philadelphia | 3 hr |
| Nov 30, 3:02 PM EST | Mesoscale Discussion | SPC | Bucks, Delaware, Montgomery, Philadelphia | 88 min |
| Nov 30, 4:37 PM EST | Mesoscale Discussion | SPC | Bucks, Philadelphia | 53 min |
| Dec 16, 8:38 AM EST | Mesoscale Discussion | SPC | Bedford, Fulton | 6 hr |
| Dec 16, 1:57 PM EST | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Blair, Carbon, Centre and 19 more | 5 hr |
| Dec 16, 6:48 PM EST | Mesoscale Discussion | SPC | Carbon, Columbia, Lackawanna, Luzerne, Monroe, Northampton and 5 more | 5 hr |
| Dec 16, 10:12 PM EST | Mesoscale Discussion | SPC | Bradford, Lackawanna, Lycoming, Sullivan, Susquehanna, Tioga and 2 more | 6 hr |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- York County34
- Chester County34
- Montgomery County34
- Lancaster County34
- Philadelphia County33
- Bucks County32
- Delaware County31
- Northampton County31
- Adams County30
- Cumberland County30
- Franklin County28
- Dauphin County28
- Berks County28
- Lehigh County28
- Fulton County27
- Perry County26
- Lebanon County26
- Monroe County26
- Carbon County25
- Wyoming County25
- Wayne County25
- Susquehanna County24
- Pike County24
- Juniata County23
- Northumberland County23
- Schuylkill County23
- Clarion County22
- Columbia County22
- Montour County22
- Butler County21
- Snyder County21
- Sullivan County21
- Lawrence County21
- Huntingdon County20
- Beaver County20
- Jefferson County20
- Washington County20
- Lackawanna County20
- Luzerne County20
- Crawford County19
27 more counties
- Armstrong County19
- Elk County19
- Forest County19
- McKean County19
- Venango County19
- Bedford County19
- Union County19
- Mercer County19
- Allegheny County18
- Westmoreland County18
- Blair County18
- Mifflin County18
- Indiana County17
- Warren County17
- Greene County16
- Centre County16
- Bradford County15
- Cameron County15
- Potter County15
- Cambria County15
- Clearfield County14
- Clinton County14
- Tioga County13
- Erie County13
- Fayette County13
- Somerset County13
- Lycoming County13
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20192021
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.