Alert archive / Maryland / Severe Thunderstorm Warnings
Severe Thunderstorm Warnings in Maryland, 2010
218 severe thunderstorm warnings in 2010. 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 severe thunderstorm warnings reaches back to 1986.
Severe Thunderstorm Warnings by county
Each county as a circle sized by its count in 2010. Tap one for its archive.
- Severe Thunderstorm Warnings
- 218
- Busiest month
- June64 severe thunderstorm warnings
- Busiest day
- July 25, 201014 severe thunderstorm warnings
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
152 of 218 severe thunderstorm warnings covering Maryland in 2010 had a qualifying storm report inside them; 328 of 390 hail, wind and damage reports fell inside a warning, on average 22 minutes after it went out.
Maryland, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Severe thunderstorm warnings | 218 | 152 | 30% | 390 | 84% | 22 min |
Each office's whole area, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Baltimore/Washington: severe thunderstorm warnings | 257 | 198 | 23% | 762 | 86% | 21 min |
| NWS Pittsburgh, PA: severe thunderstorm warnings | 204 | 124 | 39% | 290 | 82% | 26 min |
| NWS Philadelphia/Mount Holly: severe thunderstorm warnings | 183 | 107 | 42% | 252 | 82% | 29 min |
| NWS Wakefield, VA: severe thunderstorm warnings | 170 | 133 | 22% | 362 | 82% | 23 min |
An office's figures cover every county it serves, including across state lines.
Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.
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 25, 9:42 AM EST | Severe Thunderstorm Warning | PHI | Cecil | 63 min |
| Mar 22, 2:48 PM EDT | Severe Thunderstorm Warning | LWX | Charles | 27 min |
| Mar 22, 7:22 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 23 min |
| Apr 8, 5:30 PM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick, Washington | 45 min |
| Apr 8, 7:45 PM EDT | Severe Thunderstorm Warning | LWX | Charles, Montgomery, Prince George's | 29 min |
| Apr 8, 8:12 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Howard, Montgomery, Prince George's | 31 min |
| Apr 8, 9:25 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 37 min |
| Apr 16, 4:28 PM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick, Howard, Montgomery | 32 min |
| Apr 16, 4:55 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Carroll, Harford, Howard, Montgomery and 1 more | 50 min |
| Apr 16, 6:30 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Frederick | 30 min |
| Apr 16, 7:41 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 34 min |
| Apr 25, 5:33 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Washington | 42 min |
| Apr 25, 6:10 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Washington | 50 min |
| Apr 25, 7:04 PM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick, Howard, Montgomery, Washington | 41 min |
| Apr 25, 7:19 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Montgomery, Washington | 41 min |
| Apr 25, 7:31 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Frederick, Howard, Montgomery | 44 min |
| Apr 25, 7:54 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Frederick, Howard, Montgomery | 51 min |
| Apr 25, 8:05 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford, Howard, City of Baltimore | 40 min |
| Apr 25, 8:28 PM EDT | Severe Thunderstorm Warning | LWX | Washington | 47 min |
| Apr 25, 8:36 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Carroll, Howard, Montgomery, City of Baltimore | 39 min |
| Apr 25, 8:36 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent, Queen Anne's | 54 min |
| Apr 26, 4:33 PM EDT | Severe Thunderstorm Warning | LWX | Charles | 42 min |
| May 14, 5:54 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 51 min |
| May 14, 6:17 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery, Prince George's | 43 min |
| May 14, 6:20 PM EDT | Severe Thunderstorm Warning | LWX | Prince George's | 40 min |
| May 14, 6:28 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 34 min |
| May 14, 6:35 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 55 min |
| May 14, 6:41 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford | 64 min |
| May 14, 6:51 PM EDT | Severe Thunderstorm Warning | LWX | Charles, Prince George's | 54 min |
| May 14, 6:57 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, City of Baltimore | 63 min |
| May 14, 7:00 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 60 min |
| May 14, 7:08 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 67 min |
| May 14, 7:11 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford, City of Baltimore | 49 min |
| May 14, 7:24 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Charles, Prince George's, Saint Mary's | 39 min |
| May 14, 8:04 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's | 56 min |
| May 14, 8:10 PM EDT | Severe Thunderstorm Warning | LWX | Harford | 35 min |
| May 14, 8:12 PM EDT | Severe Thunderstorm Warning | LWX | Prince George's | 34 min |
| May 14, 8:49 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 56 min |
| May 14, 9:26 PM EDT | Severe Thunderstorm Warning | AKQ | Dorchester | 49 min |
| May 14, 9:45 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Talbot | 60 min |
| May 27, 5:59 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 22 min |
| May 27, 10:10 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 50 min |
| May 27, 10:30 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 60 min |
| May 27, 10:38 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 40 min |
| May 28, 2:36 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 39 min |
| May 28, 3:15 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 45 min |
| Jun 1, 3:10 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 50 min |
| Jun 3, 4:23 PM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick, Howard, Montgomery | 52 min |
| Jun 3, 4:42 PM EDT | Severe Thunderstorm Warning | LWX | Charles, Prince George's | 63 min |
| Jun 3, 5:01 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Howard, Montgomery | 44 min |
| Jun 3, 5:18 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Prince George's | 26 min |
| Jun 3, 5:30 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's | 45 min |
| Jun 3, 5:34 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 56 min |
| Jun 3, 5:41 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel | 35 min |
| Jun 3, 6:00 PM EDT | Severe Thunderstorm Warning | LWX | Saint Mary's | 45 min |
| Jun 3, 6:17 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 88 min |
| Jun 3, 6:20 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Saint Mary's | 25 min |
| Jun 3, 7:25 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 51 min |
| Jun 4, 3:14 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 76 min |
| Jun 4, 3:38 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Washington | 52 min |
| Jun 4, 3:48 PM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick | 42 min |
| Jun 4, 5:11 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford | 49 min |
| Jun 4, 5:57 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford | 48 min |
| Jun 4, 6:08 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Washington | 27 min |
| Jun 4, 7:53 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Harford | 67 min |
| Jun 4, 8:43 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford | 23 min |
| Jun 5, 5:38 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 67 min |
| Jun 6, 12:15 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 30 min |
| Jun 6, 1:18 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Montgomery | 27 min |
| Jun 6, 1:43 PM EDT | Severe Thunderstorm Warning | LWX | Howard, Montgomery, Prince George's | 47 min |
| Jun 6, 2:49 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 47 min |
| Jun 6, 3:58 PM EDT | Severe Thunderstorm Warning | LWX | Charles, Saint Mary's | 47 min |
| Jun 12, 2:24 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 51 min |
| Jun 12, 5:11 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 28 min |
| Jun 22, 5:41 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 49 min |
| Jun 22, 6:29 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 46 min |
| Jun 22, 6:53 PM EDT | Severe Thunderstorm Warning | LWX | Harford | 52 min |
| Jun 22, 7:12 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford | 18 min |
| Jun 22, 7:27 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 48 min |
| Jun 22, 7:32 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Howard, Montgomery, Prince George's | 43 min |
| Jun 22, 7:32 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Howard, Montgomery, Prince George's | 43 min |
| Jun 22, 7:52 PM EDT | Severe Thunderstorm Warning | LWX | Charles | 53 min |
| Jun 22, 8:00 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's | 30 min |
| Jun 22, 8:17 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel | 43 min |
| Jun 22, 8:23 PM EDT | Severe Thunderstorm Warning | LWX | Charles, Prince George's | 37 min |
| Jun 22, 8:29 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's | 46 min |
| Jun 22, 8:38 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Prince George's | 32 min |
| Jun 22, 9:12 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 18 min |
| Jun 22, 9:28 PM EDT | Severe Thunderstorm Warning | AKQ | Dorchester, Somerset, Wicomico | 47 min |
| Jun 22, 9:33 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's | 27 min |
| Jun 22, 9:46 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 59 min |
| Jun 22, 10:03 PM EDT | Severe Thunderstorm Warning | AKQ | Dorchester, Somerset, Wicomico | 42 min |
| Jun 23, 7:40 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 65 min |
| Jun 24, 12:25 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 50 min |
| Jun 24, 12:50 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 40 min |
| Jun 24, 12:56 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 64 min |
| Jun 24, 1:16 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 59 min |
| Jun 24, 1:46 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 59 min |
| Jun 24, 1:51 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 69 min |
| Jun 24, 3:29 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 61 min |
| Jun 24, 4:49 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel | 23 min |
| Jun 24, 5:18 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 87 min |
| Jun 24, 7:33 PM EDT | Severe Thunderstorm Warning | AKQ | Wicomico, Worcester | 42 min |
| Jun 24, 7:42 PM EDT | Severe Thunderstorm Warning | LWX | Saint Mary's | 33 min |
| Jun 24, 7:47 PM EDT | Severe Thunderstorm Warning | AKQ | Dorchester, Somerset, Wicomico, Worcester | 58 min |
| Jun 24, 8:30 PM EDT | Severe Thunderstorm Warning | AKQ | Worcester | 45 min |
| Jun 28, 1:55 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 50 min |
| Jun 28, 2:41 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery, Prince George's | 49 min |
| Jun 28, 3:10 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 65 min |
| Jun 28, 3:56 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's | 64 min |
| Jul 12, 2:48 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford, City of Baltimore | 42 min |
| Jul 12, 2:52 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Howard, City of Baltimore | 38 min |
| Jul 12, 3:24 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Prince George's | 51 min |
| Jul 12, 11:25 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll | 19 min |
| Jul 13, 8:45 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Prince George's | 45 min |
| Jul 13, 8:53 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Saint Mary's | 43 min |
| Jul 13, 9:21 PM EDT | Severe Thunderstorm Warning | PHI | Kent, Queen Anne's, Talbot | 64 min |
| Jul 13, 9:41 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 64 min |
| Jul 17, 1:24 AM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's | 51 min |
| Jul 18, 11:18 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 27 min |
| Jul 18, 11:31 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Howard, Montgomery, Prince George's, City of Baltimore | 44 min |
| Jul 19, 12:00 AM EDT | Severe Thunderstorm Warning | PHI | Caroline, Cecil, Kent, Queen Anne's, Talbot | 60 min |
| Jul 19, 12:15 AM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford | 17 min |
| Jul 19, 5:39 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 66 min |
| Jul 19, 6:22 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 53 min |
| Jul 19, 8:23 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's | 52 min |
| Jul 20, 12:26 PM EDT | Severe Thunderstorm Warning | LWX | Harford | 34 min |
| Jul 20, 4:44 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Carroll, Howard, City of Baltimore | 46 min |
| Jul 20, 5:35 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, City of Baltimore | 25 min |
| Jul 20, 7:54 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Harford | 51 min |
| Jul 25, 12:27 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 78 min |
| Jul 25, 12:54 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 66 min |
| Jul 25, 1:20 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 55 min |
| Jul 25, 1:30 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 75 min |
| Jul 25, 2:01 PM EDT | Severe Thunderstorm Warning | LWX | Allegany, Washington | 44 min |
| Jul 25, 2:25 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 80 min |
| Jul 25, 2:29 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Frederick, Harford, Howard, City of Baltimore | 61 min |
| Jul 25, 2:36 PM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick, Howard, Montgomery, Washington | 54 min |
| Jul 25, 3:07 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Charles, Howard, Montgomery, Prince George's | 38 min |
| Jul 25, 3:22 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Cecil, Kent, Queen Anne's | 53 min |
| Jul 25, 3:42 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Howard, Montgomery, Prince George's | 63 min |
| Jul 25, 4:11 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 94 min |
| Jul 25, 4:17 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Charles, Saint Mary's | 58 min |
| Jul 25, 5:30 PM EDT | Severe Thunderstorm Warning | AKQ | Somerset, Wicomico, Worcester | 45 min |
| Jul 29, 12:31 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Howard, Montgomery | 44 min |
| Jul 29, 1:10 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Carroll, Harford, Howard, City of Baltimore | 50 min |
| Jul 29, 1:16 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Montgomery, Prince George's | 28 min |
| Jul 29, 1:50 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 85 min |
| Jul 29, 2:53 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 41 min |
| Jul 29, 3:58 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Howard, City of Baltimore | 25 min |
| Aug 4, 5:09 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 66 min |
| Aug 4, 5:34 PM EDT | Severe Thunderstorm Warning | LWX | Allegany | 56 min |
| Aug 4, 6:10 PM EDT | Severe Thunderstorm Warning | LWX | Allegany, Washington | 65 min |
| Aug 4, 6:59 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Montgomery, Washington | 61 min |
| Aug 4, 7:56 PM EDT | Severe Thunderstorm Warning | LWX | Charles | 64 min |
| Aug 4, 8:00 PM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick | 45 min |
| Aug 4, 8:46 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Harford | 59 min |
| Aug 5, 3:01 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery, Prince George's | 44 min |
| Aug 5, 3:45 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's | 60 min |
| Aug 5, 3:53 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 52 min |
| Aug 5, 4:17 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 58 min |
| Aug 5, 4:29 PM EDT | Severe Thunderstorm Warning | AKQ | Dorchester | 61 min |
| Aug 5, 5:15 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Queen Anne's, Talbot | 60 min |
| Aug 5, 5:22 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Charles, Saint Mary's | 53 min |
| Aug 5, 5:29 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery, Prince George's | 46 min |
| Aug 5, 5:48 PM EDT | Severe Thunderstorm Warning | AKQ | Somerset, Wicomico, Worcester | 42 min |
| Aug 5, 6:29 PM EDT | Severe Thunderstorm Warning | AKQ | Somerset, Wicomico, Worcester | 46 min |
| Aug 5, 7:01 PM EDT | Severe Thunderstorm Warning | AKQ | Worcester | 44 min |
| Aug 12, 6:10 AM EDT | Severe Thunderstorm Warning | LWX | Carroll, Frederick, Howard, Montgomery | 35 min |
| Aug 12, 6:28 AM EDT | Severe Thunderstorm Warning | LWX | Frederick, Howard, Montgomery | 32 min |
| Aug 12, 7:07 AM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Montgomery, Prince George's | 38 min |
| Aug 12, 7:40 AM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Montgomery, Prince George's | 50 min |
| Aug 12, 8:12 AM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's | 63 min |
| Aug 12, 8:24 AM EDT | Severe Thunderstorm Warning | PHI | Queen Anne's, Talbot | 66 min |
| Aug 12, 8:28 AM EDT | Severe Thunderstorm Warning | AKQ | Dorchester, Wicomico | 47 min |
| Aug 12, 9:16 AM EDT | Severe Thunderstorm Warning | AKQ | Dorchester, Somerset, Wicomico, Worcester | 59 min |
| Aug 12, 10:09 AM EDT | Severe Thunderstorm Warning | AKQ | Somerset, Wicomico, Worcester | 66 min |
| Aug 12, 4:15 PM EDT | Severe Thunderstorm Warning | LWX | Charles | 60 min |
| Aug 12, 4:35 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Frederick, Washington | 55 min |
| Aug 12, 5:13 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Carroll, Frederick, Howard, Montgomery and 2 more | 62 min |
| Sep 16, 4:23 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 43 min |
| Sep 16, 4:36 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 54 min |
| Sep 16, 9:46 PM EDT | Severe Thunderstorm Warning | PBZ | Garrett | 28 min |
| Sep 16, 10:54 PM EDT | Severe Thunderstorm Warning | LWX | Allegany, Frederick, Washington | 51 min |
| Sep 22, 2:49 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 41 min |
| Sep 22, 4:48 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Harford | 42 min |
| Sep 22, 7:31 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Howard, Montgomery, Prince George's | 44 min |
| Sep 22, 7:57 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Prince George's | 48 min |
| Sep 22, 8:02 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Harford | 43 min |
| Sep 22, 8:39 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel | 26 min |
| Sep 22, 8:43 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford | 35 min |
| Sep 22, 8:43 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 47 min |
| Sep 22, 9:10 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 65 min |
| Sep 28, 6:44 AM EDT | Severe Thunderstorm Warning | LWX | Allegany, Washington | 46 min |
| Sep 28, 10:22 AM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent, Queen Anne's | 53 min |
| Sep 30, 8:45 AM EDT | Severe Thunderstorm Warning | LWX | Harford | 45 min |
| Sep 30, 10:49 AM EDT | Severe Thunderstorm Warning | LWX | Howard, Montgomery, Prince George's | 26 min |
| Oct 11, 9:57 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel | 37 min |
| Oct 11, 10:20 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 55 min |
| Oct 27, 1:25 PM EDT | Severe Thunderstorm Warning | LWX | Charles, Prince George's | 50 min |
| Oct 27, 3:31 PM EDT | Severe Thunderstorm Warning | PHI | Caroline | 59 min |
| Oct 27, 7:30 PM EDT | Severe Thunderstorm Warning | AKQ | Somerset, Worcester | 45 min |
| Oct 27, 9:06 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Talbot | 54 min |
| Nov 16, 11:59 PM EST | Severe Thunderstorm Warning | LWX | Carroll, Frederick, Howard, Washington | 46 min |
| Nov 17, 12:03 AM EST | Severe Thunderstorm Warning | LWX | Charles, Prince George's | 42 min |
| Nov 17, 12:35 AM EST | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Howard, Montgomery, Prince George's | 40 min |
| Nov 17, 12:43 AM EST | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's | 47 min |
| Nov 17, 1:04 AM EST | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Calvert, Carroll, Charles, Harford and 5 more | 86 min |
| Nov 17, 1:08 AM EST | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 52 min |
| Nov 17, 2:03 AM EST | Severe Thunderstorm Warning | PHI | Caroline, Cecil, Kent, Queen Anne's, Talbot | 57 min |
| Dec 1, 4:22 AM EST | Severe Thunderstorm Warning | LWX | Allegany, Washington | 22 min |
| Dec 1, 5:44 AM EST | Severe Thunderstorm Warning | LWX | Frederick, Montgomery | 26 min |
| Dec 1, 6:37 AM EST | Severe Thunderstorm Warning | LWX | Calvert, Charles, Saint Mary's | 53 min |
| Dec 1, 6:55 AM EST | Severe Thunderstorm Warning | PHI | Caroline, Cecil, Kent, Queen Anne's, Talbot | 65 min |
| Dec 1, 7:25 AM EST | Severe Thunderstorm Warning | LWX | Frederick, Montgomery, Washington | 35 min |
| Dec 1, 8:03 AM EST | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Frederick, Howard, Montgomery | 42 min |
| Dec 1, 9:00 AM EST | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Carroll, Harford, Howard, City of Baltimore | 75 min |
| Dec 1, 10:33 AM EST | Severe Thunderstorm Warning | PHI | Caroline, Cecil, Kent, Queen Anne's, Talbot | 42 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Montgomery County46
- Prince George's County37
- Anne Arundel County37
- Baltimore County35
- Howard County33
- Queen Anne's County33
- Caroline County32
- Carroll County28
- Frederick County28
- Cecil County27
- Kent County27
- Charles County25
- Talbot County25
- Harford County24
- Washington County19
- Calvert County16
- Allegany County15
- City of Baltimore15
- Saint Mary's County14
- Garrett County12
- Wicomico County10
- Worcester County10
- Somerset County9
- Dorchester County7
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20092011
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.