Alert archive / Maryland / Carroll County
Weather alerts in Carroll County, Maryland, 2011
225 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Carroll County and its neighbors
Each county as a circle sized by its count in 2011. Tap one for its archive.
- Alerts
- 225
- Warnings
- 64
- Watches
- 48
- Advisories
- 24
- Busiest month
- April46 alerts
- Busiest day
- April 28, 201114 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
2 of 10 tornado warnings covering Carroll County in 2011 had a tornado report inside them; 1 of 3 tornado reports fell inside a warning, on average 1 minutes after it went out.
Carroll County, 2011
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 10 | 2 | 80% | 3 | 33% | 1 min |
| Severe thunderstorm warnings | 18 | 16 | 11% | 28 | 93% | 17 min |
| Flash flood warnings | 18 | 10 | 44% | 3 | 100% | 103 min |
Each office's whole area, 2011
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Baltimore/Washington: tornado warnings | 96 | 27 | 72% | 45 | 67% | 11 min |
| NWS Baltimore/Washington: severe thunderstorm warnings | 440 | 335 | 24% | 963 | 78% | 18 min |
| NWS Baltimore/Washington: flash flood warnings | 170 | 99 | 42% | 341 | 84% | 121 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 | Lasted |
|---|---|---|---|
| Jan 7, 6:50 PM EST | Winter Weather Advisory | LWX | 35 hr |
| Jan 10, 4:03 AM EST | Winter Storm Watch | LWX | 18 hr |
| Jan 10, 9:39 PM EST | Winter Weather Advisory | LWX | 55 hr |
| Jan 17, 2:44 PM EST | Winter Weather Advisory | LWX | 20 hr |
| Jan 17, 10:37 PM EST | Winter Storm Warning | LWX | 10 hr |
| Jan 18, 11:32 PM EST | Freezing Rain Advisory | LWX | 6 hr |
| Jan 20, 8:54 AM EST | Winter Weather Advisory | LWX | 24 hr |
| Jan 25, 10:16 AM EST | Winter Storm Watch | LWX | 18 hr |
| Jan 25, 6:02 PM EST | Winter Storm Warning | LWX | 29 hr |
| Jan 26, 2:19 PM EST | Mesoscale Discussion | SPC | 6 hr |
| Jan 31, 4:07 AM EST | Winter Storm Watch | LWX | 32 hr |
| Jan 31, 2:40 PM EST | Winter Weather Advisory | LWX | 21 hr |
| Feb 1, 11:57 AM EST | Freezing Rain Advisory | LWX | 19 hr |
| Feb 1, 8:39 PM EST | Mesoscale Discussion | SPC | 6 hr |
| Feb 4, 2:44 PM EST | Freezing Rain Advisory | LWX | 22 hr |
| Feb 8, 3:26 AM EST | Wind Advisory | LWX | 13 hr |
| Feb 14, 2:45 AM EST | Wind Advisory | LWX | 22 hr |
| Feb 18, 3:16 AM EST | Fire Weather Watch | LWX | 11 hr |
| Feb 18, 10:30 AM EST | High Wind Watch | LWX | 7 hr |
| Feb 18, 2:03 PM EST | Red Flag Warning | LWX | 31 hr |
| Feb 18, 5:22 PM EST | High Wind Warning | LWX | 26 hr |
| Feb 18, 5:22 PM EST | Wind Advisory | LWX | 19 hr |
| Feb 19, 6:33 PM EST | Wind Advisory | LWX | 5 hr |
| Feb 21, 3:51 AM EST | Winter Storm Watch | LWX | 8 hr |
| Feb 21, 11:57 AM EST | Winter Storm Warning | LWX | 18 hr |
| Feb 21, 5:58 PM EST | Mesoscale Discussion | SPC | 4 hr |
| Feb 24, 4:05 AM EST | High Wind Watch | LWX | 10 hr |
| Feb 24, 1:41 PM EST | Wind Advisory | LWX | 24 hr |
| Feb 24, 8:36 PM EST | High Wind Warning | LWX | 22 hr |
| Feb 25, 11:22 AM EST | Special Weather Statement | LWX | 53 min |
| Feb 28, 8:36 AM EST | Mesoscale Discussion | SPC | 24 min |
| Feb 28, 8:57 AM EST | Tornado Watch | SPC | 9 hr |
| Feb 28, 10:17 AM EST | Special Weather Statement | LWX | 28 min |
| Mar 5, 3:16 AM EST | Flood Watch | LWX | 43 hr |
| Mar 8, 3:14 AM EST | Flood Watch | LWX | 65 hr |
| Mar 10, 6:07 PM EST | Flash Flood Warning | LWX | 3 hr |
| Mar 10, 6:29 PM EST | Flash Flood Warning | LWX | 4 hr |
| Mar 10, 7:30 PM EST | Special Weather Statement | LWX | 30 min |
| Mar 21, 6:22 AM EDT | Special Weather Statement | LWX | 23 min |
| Mar 23, 4:13 PM EDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Mar 23, 6:07 PM EDT | Special Weather Statement | LWX | 23 min |
| Mar 23, 6:29 PM EDT | Special Weather Statement | LWX | 31 min |
| Mar 23, 7:34 PM EDT | Special Weather Statement | LWX | 56 min |
| Apr 3, 9:46 PM EDT | Special Weather Statement | LWX | 44 min |
| Apr 5, 2:18 AM EDT | Tornado Watch | SPC | 8 hr |
| Apr 5, 3:34 AM EDT | Mesoscale Discussion | SPC | 116 min |
| Apr 5, 3:56 AM EDT | Special Weather Statement | LWX | 64 min |
| Apr 5, 4:40 AM EDT | Severe Thunderstorm Warning | LWX | 53 min |
| Apr 11, 6:43 PM EDT | Mesoscale Discussion | SPC | 62 min |
| Apr 15, 4:34 AM EDT | Flash Flood Watch | LWX | 41 hr |
| Apr 16, 1:29 PM EDT | Tornado Watch | SPC | 8 hr |
| Apr 16, 4:29 PM EDT | Mesoscale Discussion | SPC | 31 min |
| Apr 16, 4:59 PM EDT | Severe Thunderstorm Warning | LWX | 46 min |
| Apr 16, 6:38 PM EDT | Mesoscale Discussion | SPC | 97 min |
| Apr 16, 7:38 PM EDT | Severe Thunderstorm Warning | LWX | 52 min |
| Apr 16, 7:39 PM EDT | Special Weather Statement | LWX | 66 min |
| Apr 16, 7:46 PM EDT | Tornado Warning | LWX | 26 min |
| Apr 16, 8:02 PM EDT | Tornado Warning | LWX | 28 min |
| Apr 16, 8:12 PM EDT | Mesoscale Discussion | SPC | 63 min |
| Apr 16, 8:18 PM EDT | Severe Thunderstorm Warning | LWX | 42 min |
| Apr 17, 4:02 AM EDT | Special Weather Statement | LWX | 58 min |
| Apr 19, 9:54 AM EDT | Flood Watch | LWX | 8 hr |
| Apr 24, 2:12 PM EDT | Mesoscale Discussion | SPC | 93 min |
| Apr 24, 3:40 PM EDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Apr 24, 4:30 PM EDT | Severe Thunderstorm Warning | LWX | 45 min |
| Apr 24, 6:10 PM EDT | Mesoscale Discussion | SPC | 65 min |
| Apr 27, 9:51 AM EDT | Flash Flood Watch | LWX | 29 hr |
| Apr 27, 1:23 PM EDT | Tornado Watch | SPC | 5 hr |
| Apr 27, 4:39 PM EDT | Mesoscale Discussion | SPC | 66 min |
| Apr 27, 6:00 PM EDT | Mesoscale Discussion | SPC | 60 min |
| Apr 27, 6:15 PM EDT | Tornado Watch | SPC | 6 hr |
| Apr 27, 6:50 PM EDT | Mesoscale Discussion | SPC | 55 min |
| Apr 27, 7:16 PM EDT | Special Weather Statement | LWX | 29 min |
| Apr 27, 7:31 PM EDT | Tornado Warning | LWX | 29 min |
| Apr 27, 7:55 PM EDT | Mesoscale Discussion | SPC | 65 min |
| Apr 28, 12:41 AM EDT | Tornado Watch | SPC | 7 hr |
| Apr 28, 4:24 AM EDT | Tornado Warning | LWX | 51 min |
| Apr 28, 7:05 AM EDT | Tornado Warning | LWX | 25 min |
| Apr 28, 7:17 AM EDT | Tornado Warning | LWX | 28 min |
| Apr 28, 7:27 AM EDT | Flash Flood Warning | LWX | 5 hr |
| Apr 28, 7:38 AM EDT | Tornado Watch | SPC | 7 hr |
| Apr 28, 7:55 AM EDT | Tornado Warning | LWX | 27 min |
| Apr 28, 8:12 AM EDT | Tornado Warning | LWX | 33 min |
| Apr 28, 8:45 AM EDT | Tornado Warning | LWX | 30 min |
| Apr 28, 9:14 AM EDT | Tornado Warning | LWX | 31 min |
| Apr 28, 10:10 AM EDT | Special Weather Statement | LWX | 50 min |
| Apr 28, 10:36 AM EDT | Flash Flood Warning | LWX | 102 min |
| Apr 28, 10:44 AM EDT | Mesoscale Discussion | SPC | 61 min |
| Apr 28, 12:15 PM EDT | Areal Flood Warning | LWX | 3 hr |
| May 3, 2:27 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| May 6, 6:34 PM EDT | Special Weather Statement | LWX | 26 min |
| May 16, 5:35 PM EDT | Special Weather Statement | LWX | 70 min |
| May 17, 3:45 AM EDT | Flash Flood Watch | LWX | 44 hr |
| May 17, 6:27 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| May 18, 11:55 AM EDT | Mesoscale Discussion | SPC | 65 min |
| May 18, 12:55 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
| May 18, 3:08 PM EDT | Mesoscale Discussion | SPC | 67 min |
| May 18, 6:01 PM EDT | Mesoscale Discussion | SPC | 89 min |
| May 19, 4:36 AM EDT | Flash Flood Watch | LWX | 14 hr |
| May 23, 10:33 AM EDT | Mesoscale Discussion | SPC | 87 min |
| May 23, 10:48 AM EDT | Severe Thunderstorm Watch | SPC | 9 hr |
| May 23, 2:33 PM EDT | Mesoscale Discussion | SPC | 87 min |
| May 23, 4:40 PM EDT | Mesoscale Discussion | SPC | 95 min |
| May 23, 5:36 PM EDT | Special Weather Statement | LWX | 24 min |
| May 24, 4:44 PM EDT | Severe Thunderstorm Warning | LWX | 19 min |
| May 27, 12:24 PM EDT | Mesoscale Discussion | SPC | 96 min |
| May 27, 12:57 PM EDT | Severe Thunderstorm Watch | SPC | 9 hr |
| May 27, 6:14 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| May 27, 7:55 PM EDT | Severe Thunderstorm Warning | LWX | 50 min |
| May 27, 8:08 PM EDT | Severe Thunderstorm Warning | LWX | 22 min |
| May 27, 8:28 PM EDT | Severe Thunderstorm Warning | LWX | 47 min |
| May 29, 1:46 PM EDT | Heat Advisory | LWX | 31 hr |
| May 30, 8:37 PM EDT | Heat Advisory | LWX | 23 hr |
| May 31, 1:26 PM EDT | Heat Advisory | LWX | 31 hr |
| Jun 1, 1:37 PM EDT | Mesoscale Discussion | SPC | 83 min |
| Jun 1, 2:24 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 1, 4:12 PM EDT | Special Weather Statement | LWX | 33 min |
| Jun 7, 1:33 PM EDT | Heat Advisory | LWX | 30 hr |
| Jun 8, 1:28 PM EDT | Heat Advisory | LWX | 31 hr |
| Jun 9, 12:53 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 9, 6:17 PM EDT | Mesoscale Discussion | SPC | 58 min |
| Jun 9, 7:10 PM EDT | Special Weather Statement | LWX | 35 min |
| Jun 9, 7:31 PM EDT | Severe Thunderstorm Warning | LWX | 44 min |
| Jun 9, 7:45 PM EDT | Special Weather Statement | LWX | 30 min |
| Jun 9, 8:15 PM EDT | Severe Thunderstorm Warning | LWX | 45 min |
| Jun 10, 5:28 PM EDT | Mesoscale Discussion | SPC | 92 min |
| Jun 11, 8:00 PM EDT | Special Weather Statement | LWX | 30 min |
| Jun 11, 8:18 PM EDT | Severe Thunderstorm Warning | LWX | 42 min |
| Jun 11, 9:05 PM EDT | Special Weather Statement | LWX | 25 min |
| Jun 12, 12:03 PM EDT | Mesoscale Discussion | SPC | 87 min |
| Jun 12, 1:48 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 16, 6:01 PM EDT | Mesoscale Discussion | SPC | 89 min |
| Jun 22, 2:03 PM EDT | Mesoscale Discussion | SPC | 117 min |
| Jul 3, 3:14 AM EDT | Flash Flood Warning | LWX | 3 hr |
| Jul 3, 3:22 PM EDT | Mesoscale Discussion | SPC | 53 min |
| Jul 3, 4:21 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 7, 3:14 PM EDT | Flash Flood Watch | LWX | 29 hr |
| Jul 8, 1:05 AM EDT | Special Weather Statement | LWX | 40 min |
| Jul 8, 1:21 AM EDT | Special Weather Statement | LWX | 54 min |
| Jul 8, 11:44 AM EDT | Mesoscale Discussion | SPC | 61 min |
| Jul 8, 1:51 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 8, 3:01 PM EDT | Special Weather Statement | LWX | 89 min |
| Jul 8, 3:24 PM EDT | Flash Flood Warning | LWX | 3 hr |
| Jul 8, 3:33 PM EDT | Flash Flood Warning | LWX | 3 hr |
| Jul 8, 3:49 PM EDT | Flash Flood Warning | LWX | 3 hr |
| Jul 8, 5:52 PM EDT | Mesoscale Discussion | SPC | 83 min |
| Jul 11, 5:47 PM EDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 11, 7:05 PM EDT | Severe Thunderstorm Warning | LWX | 40 min |
| Jul 11, 7:34 PM EDT | Severe Thunderstorm Warning | LWX | 41 min |
| Jul 11, 7:44 PM EDT | Mesoscale Discussion | SPC | 61 min |
| Jul 11, 8:15 PM EDT | Severe Thunderstorm Warning | LWX | 45 min |
| Jul 19, 12:12 PM EDT | Excessive Heat Watch | LWX | 27 hr |
| Jul 19, 3:20 PM EDT | Special Weather Statement | LWX | 55 min |
| Jul 20, 3:19 PM EDT | Excessive Heat Warning | LWX | 31 hr |
| Jul 20, 3:19 PM EDT | Excessive Heat Warning | LWX | 54 hr |
| Jul 21, 3:38 PM EDT | Excessive Heat Warning | LWX | 52 hr |
| Jul 22, 3:17 PM EDT | Mesoscale Discussion | SPC | 58 min |
| Jul 23, 3:29 PM EDT | Heat Advisory | LWX | 29 hr |
| Jul 25, 12:25 PM EDT | Special Weather Statement | LWX | 35 min |
| Jul 25, 12:55 PM EDT | Special Weather Statement | LWX | 35 min |
| Jul 25, 1:12 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 25, 1:28 PM EDT | Severe Thunderstorm Warning | LWX | 32 min |
| Jul 28, 12:53 PM EDT | Heat Advisory | LWX | 31 hr |
| Jul 29, 6:17 PM EDT | Mesoscale Discussion | SPC | 88 min |
| Aug 1, 3:22 PM EDT | Mesoscale Discussion | SPC | 83 min |
| Aug 13, 2:07 PM EDT | Mesoscale Discussion | SPC | 113 min |
| Aug 13, 2:54 PM EDT | Special Weather Statement | LWX | 66 min |
| Aug 14, 3:23 AM EDT | Flash Flood Watch | LWX | 20 hr |
| Aug 14, 10:18 PM EDT | Special Weather Statement | LWX | 42 min |
| Aug 14, 11:27 PM EDT | Flash Flood Warning | LWX | 77 min |
| Aug 15, 12:10 PM EDT | Flash Flood Watch | LWX | 6 hr |
| Aug 18, 1:55 PM EDT | Special Weather Statement | LWX | 35 min |
| Aug 18, 5:20 PM EDT | Severe Thunderstorm Warning | LWX | 40 min |
| Aug 18, 6:01 PM EDT | Flash Flood Warning | LWX | 81 min |
| Aug 18, 6:39 PM EDT | Special Weather Statement | LWX | 36 min |
| Aug 18, 11:16 PM EDT | Special Weather Statement | LWX | 29 min |
| Aug 19, 11:54 AM EDT | Flash Flood Watch | LWX | 8 hr |
| Aug 19, 4:51 PM EDT | Special Weather Statement | LWX | 39 min |
| Aug 21, 11:10 AM EDT | Flash Flood Watch | LWX | 7 hr |
| Aug 21, 11:54 AM EDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 21, 12:52 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 21, 7:12 PM EDT | Mesoscale Discussion | SPC | 63 min |
| Aug 21, 7:53 PM EDT | Special Weather Statement | LWX | 7 min |
| Aug 25, 8:18 AM EDT | Flash Flood Watch | LWX | 12 hr |
| Aug 26, 5:06 AM EDT | Flash Flood Watch | LWX | 47 hr |
| Aug 27, 9:38 PM EDT | Flash Flood Warning | LWX | 6 hr |
| Sep 3, 8:43 AM EDT | Special Weather Statement | LWX | 32 min |
| Sep 3, 9:21 AM EDT | Special Weather Statement | LWX | 24 min |
| Sep 4, 11:54 PM EDT | Special Weather Statement | LWX | 66 min |
| Sep 5, 4:06 AM EDT | Flash Flood Watch | LWX | 5 days |
| Sep 5, 10:17 PM EDT | Flash Flood Warning | LWX | 2 hr |
| Sep 7, 1:19 AM EDT | Special Weather Statement | LWX | 56 min |
| Sep 7, 11:33 AM EDT | Flash Flood Warning | LWX | 10 hr |
| Sep 7, 1:14 PM EDT | Flash Flood Warning | LWX | 3 hr |
| Sep 7, 5:25 PM EDT | Areal Flood Warning | LWX | 6 hr |
| Sep 7, 10:03 PM EDT | Flash Flood Warning | LWX | 6 hr |
| Sep 7, 11:37 PM EDT | Flash Flood Warning | LWX | 3 hr |
| Sep 8, 4:02 AM EDT | Areal Flood Warning | LWX | 20 hr |
| Sep 8, 6:25 PM EDT | Flash Flood Warning | LWX | 74 min |
| Sep 11, 4:13 AM EDT | Flash Flood Watch | LWX | 20 hr |
| Sep 11, 5:18 PM EDT | Special Weather Statement | LWX | 27 min |
| Sep 11, 6:38 PM EDT | Mesoscale Discussion | SPC | 97 min |
| Sep 14, 3:22 PM EDT | Mesoscale Discussion | SPC | 53 min |
| Sep 14, 6:32 PM EDT | Severe Thunderstorm Warning | LWX | 43 min |
| Sep 14, 7:13 PM EDT | Special Weather Statement | LWX | 47 min |
| Sep 14, 8:05 PM EDT | Special Weather Statement | LWX | 55 min |
| Sep 22, 12:27 AM EDT | Special Weather Statement | LWX | 63 min |
| Sep 22, 11:44 AM EDT | Flash Flood Watch | LWX | 32 hr |
| Sep 23, 11:13 AM EDT | Flash Flood Warning | LWX | 4 hr |
| Sep 23, 2:57 PM EDT | Areal Flood Warning | LWX | 99 min |
| Sep 23, 9:31 PM EDT | Dense Fog Advisory | LWX | 11 hr |
| Sep 27, 2:15 PM EDT | Flash Flood Watch | LWX | 6 hr |
| Sep 29, 5:04 AM EDT | Dense Fog Advisory | LWX | 4 hr |
| Oct 13, 7:54 PM EDT | Special Weather Statement | LWX | 21 min |
| Oct 26, 4:24 PM EDT | Freeze Watch | LWX | 23 hr |
| Oct 27, 3:08 PM EDT | Frost Advisory | LWX | 17 hr |
| Oct 28, 3:36 AM EDT | Winter Storm Watch | LWX | 15 hr |
| Oct 28, 2:31 PM EDT | Winter Storm Warning | LWX | 27 hr |
| Oct 29, 12:34 AM EDT | Mesoscale Discussion | SPC | 6 hr |
| Oct 29, 5:30 AM EDT | Winter Storm Warning | LWX | 13 hr |
| Oct 29, 10:32 AM EDT | Freeze Warning | LWX | 22 hr |
| Nov 23, 12:41 AM EST | Areal Flood Warning | LWX | 3 hr |
| Nov 23, 3:36 AM EST | Areal Flood Warning | LWX | 6 hr |
| Dec 6, 8:24 PM EST | Flood Watch | LWX | 29 hr |
| Dec 7, 4:30 AM EST | Winter Weather Advisory | LWX | 20 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20102012
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.