Alert archive / Maryland / Calvert County
Weather alerts in Calvert County, Maryland, 2023
105 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Calvert County and its neighbors
Each county as a circle sized by its count in 2023. Tap one for its archive.
- Alerts
- 105
- Warnings
- 28
- Watches
- 23
- Advisories
- 24
- Busiest month
- July37 alerts
- Busiest day
- July 29, 20238 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Calvert County, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 19 | 13 | 32% | 2 | 100% | 17 min |
| Flash flood warnings | 2 | 0 | 100% | 0 |
Each office's whole area, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Baltimore/Washington: tornado warnings | 15 | 1 | 93% | 2 | 50% | 0 min |
| NWS Baltimore/Washington: severe thunderstorm warnings | 370 | 286 | 23% | 992 | 89% | 21 min |
| NWS Baltimore/Washington: flash flood warnings | 48 | 23 | 52% | 47 | 98% | 48 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 |
|---|---|---|---|
| Mar 1, 2:43 AM EST | Coastal Flood Advisory | LWX | 20 hr |
| Mar 3, 9:51 AM EST | Coastal Flood Advisory | LWX | 24 hr |
| Mar 3, 12:33 PM EST | Wind Advisory | LWX | 26 hr |
| Mar 12, 2:49 PM EDT | Coastal Flood Advisory | LWX | 29 hr |
| Mar 13, 2:38 PM EDT | Wind Advisory | LWX | 33 hr |
| Mar 31, 2:29 PM EDT | High Wind Warning | LWX | 35 hr |
| Mar 31, 2:29 PM EDT | Wind Advisory | LWX | 35 hr |
| Apr 1, 7:40 PM EDT | Severe Thunderstorm Warning | LWX | 35 min |
| Apr 6, 2:00 PM EDT | Mesoscale Discussion | SPC | 90 min |
| Apr 6, 2:58 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Apr 6, 4:44 PM EDT | Mesoscale Discussion | SPC | 91 min |
| Apr 6, 5:53 PM EDT | Severe Thunderstorm Warning | LWX | 35 min |
| Apr 6, 6:08 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 6, 8:27 PM EDT | Mesoscale Discussion | SPC | 93 min |
| Apr 9, 9:08 AM EDT | Frost Advisory | LWX | 24 hr |
| Apr 11, 3:46 PM EDT | Fire Weather Watch | LWX | 17 hr |
| Apr 17, 12:25 PM EDT | Fire Weather Watch | LWX | 15 hr |
| Apr 18, 3:14 AM EDT | Red Flag Warning | LWX | 17 hr |
| Apr 22, 9:34 AM EDT | Mesoscale Discussion | SPC | 116 min |
| Apr 22, 10:07 AM EDT | Severe Thunderstorm Watch | SPC | 10 hr |
| Apr 22, 2:12 PM EDT | Mesoscale Discussion | SPC | 93 min |
| Apr 22, 2:14 PM EDT | Severe Thunderstorm Warning | LWX | 46 min |
| Apr 27, 2:57 PM EDT | Coastal Flood Advisory | LWX | 37 hr |
| Apr 30, 6:48 AM EDT | Coastal Flood Advisory | LWX | 11 hr |
| Apr 30, 5:59 PM EDT | Coastal Flood Advisory | LWX | 11 hr |
| Jun 4, 9:16 AM EDT | Coastal Flood Advisory | LWX | 26 hr |
| Jun 16, 10:50 AM EDT | Mesoscale Discussion | SPC | 55 min |
| Jun 16, 1:22 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 16, 6:49 PM EDT | Mesoscale Discussion | SPC | 86 min |
| Jun 16, 7:02 PM EDT | Severe Thunderstorm Warning | LWX | 43 min |
| Jun 21, 5:52 AM EDT | Coastal Flood Advisory | LWX | 30 hr |
| Jun 26, 12:36 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 26, 8:03 PM EDT | Mesoscale Discussion | SPC | 87 min |
| Jun 27, 2:43 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 1, 1:37 PM EDT | Mesoscale Discussion | SPC | 113 min |
| Jul 1, 4:17 PM EDT | Severe Thunderstorm Warning | LWX | 43 min |
| Jul 2, 2:06 PM EDT | Mesoscale Discussion | SPC | 114 min |
| Jul 2, 4:31 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 3, 1:42 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 3, 2:55 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 3, 4:49 PM EDT | Mesoscale Discussion | SPC | 116 min |
| Jul 3, 5:53 PM EDT | Severe Thunderstorm Warning | LWX | 42 min |
| Jul 3, 8:29 PM EDT | Mesoscale Discussion | SPC | 91 min |
| Jul 8, 3:23 PM EDT | Flood Watch | LWX | 25 hr |
| Jul 9, 12:55 PM EDT | Mesoscale Discussion | SPC | 65 min |
| Jul 9, 1:19 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 9, 4:08 PM EDT | Mesoscale Discussion | SPC | 97 min |
| Jul 14, 2:02 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 14, 7:16 PM EDT | Severe Thunderstorm Warning | LWX | 44 min |
| Jul 15, 6:38 PM EDT | Flood Watch | LWX | 23 hr |
| Jul 16, 11:55 AM EDT | Flash Flood Warning | LWX | 3 hr |
| Jul 19, 4:48 PM EDT | Mesoscale Discussion | SPC | 87 min |
| Jul 21, 4:26 AM EDT | Mesoscale Discussion | SPC | 94 min |
| Jul 25, 12:13 PM EDT | Severe Thunderstorm Watch | SPC | 10 hr |
| Jul 25, 12:44 PM EDT | Flood Watch | LWX | 9 hr |
| Jul 25, 2:20 PM EDT | Severe Thunderstorm Warning | LWX | 17 min |
| Jul 25, 8:36 PM EDT | Severe Thunderstorm Warning | LWX | 39 min |
| Jul 26, 9:01 AM EDT | Heat Advisory | LWX | 35 hr |
| Jul 26, 1:57 PM EDT | Excessive Heat Watch | LWX | 24 hr |
| Jul 27, 1:48 PM EDT | Excessive Heat Warning | LWX | 29 hr |
| Jul 28, 8:33 AM EDT | Excessive Heat Warning | LWX | 34 hr |
| Jul 28, 1:54 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 28, 4:48 PM EDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 29, 1:56 PM EDT | Mesoscale Discussion | SPC | 64 min |
| Jul 29, 2:48 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 29, 4:45 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 29, 5:00 PM EDT | Severe Thunderstorm Warning | LWX | 45 min |
| Jul 29, 5:39 PM EDT | Severe Thunderstorm Warning | LWX | 66 min |
| Jul 29, 6:20 PM EDT | Mesoscale Discussion | SPC | 85 min |
| Jul 29, 6:29 PM EDT | Severe Thunderstorm Warning | LWX | 61 min |
| Jul 29, 7:30 PM EDT | Severe Thunderstorm Warning | LWX | 45 min |
| Aug 7, 1:20 PM EDT | Tornado Watch | SPC | 11 hr |
| Aug 7, 3:17 PM EDT | Mesoscale Discussion | SPC | 88 min |
| Aug 7, 5:43 PM EDT | Severe Thunderstorm Warning | LWX | 62 min |
| Aug 7, 9:32 PM EDT | Severe Thunderstorm Warning | LWX | 14 min |
| Aug 14, 3:47 PM EDT | Severe Thunderstorm Warning | LWX | 43 min |
| Aug 14, 4:31 PM EDT | Severe Thunderstorm Warning | LWX | 28 min |
| Aug 15, 1:28 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 15, 2:08 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Sep 6, 3:11 AM EDT | Heat Advisory | LWX | 16 hr |
| Sep 7, 1:14 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Sep 7, 7:17 PM EDT | Severe Thunderstorm Warning | LWX | 28 min |
| Sep 7, 7:51 PM EDT | Mesoscale Discussion | SPC | 84 min |
| Sep 8, 3:11 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Sep 8, 6:34 PM EDT | Mesoscale Discussion | SPC | 86 min |
| Sep 8, 10:31 PM EDT | Mesoscale Discussion | SPC | 59 min |
| Sep 9, 3:18 PM EDT | Flash Flood Warning | LWX | 2 hr |
| Sep 9, 4:23 PM EDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Sep 9, 4:46 PM EDT | Severe Thunderstorm Warning | LWX | 28 min |
| Sep 21, 2:46 PM EDT | Coastal Flood Watch | LWX | 31 hr |
| Sep 21, 4:59 PM EDT | Tropical Storm Warning | LWX | 51 hr |
| Sep 22, 8:50 AM EDT | Coastal Flood Advisory | LWX | 69 hr |
| Sep 26, 2:26 AM EDT | Coastal Flood Advisory | LWX | 4 days |
| Oct 13, 9:18 AM EDT | Coastal Flood Advisory | LWX | 49 hr |
| Oct 23, 9:52 AM EDT | Frost Advisory | LWX | 24 hr |
| Oct 31, 3:48 AM EDT | Freeze Watch | LWX | 23 hr |
| Nov 1, 2:26 AM EDT | Freeze Warning | LWX | 32 hr |
| Nov 20, 7:06 PM EST | Coastal Flood Advisory | LWX | 46 hr |
| Nov 21, 11:23 AM EST | Wind Advisory | LWX | 14 hr |
| Dec 2, 7:00 PM EST | Dense Fog Advisory | LWX | 7 hr |
| Dec 3, 3:14 AM EST | Dense Fog Advisory | LWX | 11 hr |
| Dec 16, 1:32 PM EST | Flood Watch | LWX | 39 hr |
| Dec 17, 3:05 AM EST | Coastal Flood Advisory | LWX | 30 hr |
| Dec 17, 3:51 AM EST | Wind Advisory | LWX | 34 hr |
| Dec 18, 12:19 AM EST | Areal Flood Warning | LWX | 5 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
| Product | Alerts |
|---|---|
| Severe storms | |
| Severe Thunderstorm Warning | 19 |
| Severe Thunderstorm Watch | 13 |
| Tornado Watch | 1 |
| Mesoscale Discussion | 30 |
| Flooding | |
| Areal Flood Warning | 1 |
| Flash Flood Warning | 2 |
| Flood Watch | 4 |
| Heat | |
| Excessive Heat Warning | 2 |
| Excessive Heat Watch | 1 |
| Heat Advisory | 2 |
| Cold | |
| Freeze Warning | 1 |
| Freeze Watch | 1 |
| Frost Advisory | 2 |
| Wind and dust | |
| High Wind Warning | 1 |
| Wind Advisory | 5 |
| Fire | |
| Red Flag Warning | 1 |
| Fire Weather Watch | 2 |
| Fog and smoke | |
| Dense Fog Advisory | 2 |
| Tropical | |
| Tropical Storm Warning | 1 |
| Coast and beach | |
| Coastal Flood Watch | 1 |
| Coastal Flood Advisory | 13 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20222024
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.