Alert archive / North Carolina / Caswell County
Weather alerts in Caswell County, North Carolina, 2021
121 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Caswell County and its neighbors
Each county as a circle sized by its count in 2021. Tap one for its archive.
- Alerts
- 121
- Warnings
- 25
- Watches
- 14
- Advisories
- 18
- Busiest month
- July27 alerts
- Busiest day
- July 17, 202111 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
0 of 3 tornado warnings covering Caswell County in 2021 had a tornado report inside them.
Caswell County, 2021
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 3 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 12 | 10 | 17% | 3 | 67% | 18 min |
| Flash flood warnings | 2 | 0 | 100% | 0 |
Each office's whole area, 2021
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Blacksburg, VA: tornado warnings | 30 | 1 | 97% | 2 | 50% | 1 min |
| NWS Blacksburg, VA: severe thunderstorm warnings | 221 | 165 | 25% | 522 | 74% | 20 min |
| NWS Blacksburg, VA: flash flood warnings | 42 | 14 | 67% | 51 | 61% | 107 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 2, 7:50 PM EST | Dense Fog Advisory | RNK | 8 hr |
| Jan 7, 4:10 AM EST | Winter Weather Advisory | RNK | 40 hr |
| Jan 16, 1:09 AM EST | Dense Fog Advisory | RNK | 8 hr |
| Jan 26, 7:40 PM EST | Dense Fog Advisory | RNK | 11 hr |
| Jan 27, 4:32 AM EST | Winter Weather Advisory | RNK | 31 hr |
| Jan 29, 3:12 PM EST | Winter Storm Watch | RNK | 14 hr |
| Jan 30, 5:19 AM EST | Winter Storm Warning | RNK | 33 hr |
| Jan 31, 2:14 PM EST | Winter Weather Advisory | RNK | 47 hr |
| Feb 5, 11:53 AM EST | Winter Storm Watch | RNK | 16 hr |
| Feb 6, 4:16 AM EST | Winter Weather Advisory | RNK | 32 hr |
| Feb 11, 4:05 AM EST | Winter Weather Advisory | RNK | 31 hr |
| Feb 12, 3:47 AM EST | Winter Storm Warning | RNK | 42 hr |
| Feb 12, 3:47 AM EST | Winter Weather Advisory | RNK | 56 hr |
| Feb 13, 2:21 AM EST | Mesoscale Discussion | SPC | 6 hr |
| Feb 16, 5:07 AM EST | Winter Storm Watch | RNK | 23 hr |
| Feb 17, 4:25 AM EST | Winter Storm Warning | RNK | 47 hr |
| Feb 18, 4:28 AM EST | Mesoscale Discussion | SPC | 6 hr |
| Feb 18, 10:23 AM EST | Mesoscale Discussion | SPC | 3 hr |
| Feb 18, 11:51 AM EST | Winter Weather Advisory | RNK | 22 hr |
| Mar 18, 4:44 PM EDT | Special Weather Statement | RNK | 31 min |
| Mar 18, 5:15 PM EDT | Special Weather Statement | RNK | 30 min |
| Mar 18, 5:32 PM EDT | Severe Thunderstorm Warning | RNK | 58 min |
| Mar 18, 5:37 PM EDT | Tornado Warning | RNK | 23 min |
| Mar 18, 5:57 PM EDT | Mesoscale Discussion | SPC | 63 min |
| Mar 18, 6:00 PM EDT | Tornado Warning | RNK | 22 min |
| Mar 18, 10:13 PM EDT | Special Weather Statement | RNK | 32 min |
| Mar 24, 2:18 AM EDT | Dense Fog Advisory | RNK | 7 hr |
| Mar 25, 1:18 AM EDT | Dense Fog Advisory | RNK | 9 hr |
| Mar 27, 1:39 PM EDT | Mesoscale Discussion | SPC | 66 min |
| Mar 27, 2:03 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Mar 27, 3:44 PM EDT | Special Weather Statement | RNK | 31 min |
| Mar 27, 4:49 PM EDT | Mesoscale Discussion | SPC | 56 min |
| Mar 28, 12:38 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Mar 28, 7:06 PM EDT | Special Weather Statement | RNK | 54 min |
| Mar 31, 12:47 PM EDT | Special Weather Statement | RNK | 28 min |
| Mar 31, 1:15 PM EDT | Special Weather Statement | RNK | 30 min |
| Mar 31, 1:43 PM EDT | Special Weather Statement | RNK | 47 min |
| Mar 31, 2:12 PM EDT | Special Weather Statement | RNK | 33 min |
| Apr 9, 3:38 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Apr 9, 6:23 PM EDT | Mesoscale Discussion | SPC | 97 min |
| Apr 10, 11:46 PM EDT | Special Weather Statement | RNK | 29 min |
| Apr 11, 12:12 AM EDT | Special Weather Statement | RNK | 48 min |
| Apr 14, 4:24 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 20, 2:52 PM EDT | Fire Weather Watch | RNK | 13 hr |
| Apr 21, 3:39 AM EDT | Freeze Warning | RNK | 29 hr |
| Apr 21, 3:49 AM EDT | Red Flag Warning | RNK | 16 hr |
| Apr 22, 3:27 AM EDT | Freeze Watch | RNK | 8 hr |
| Apr 22, 3:27 AM EDT | Freeze Warning | RNK | 30 hr |
| Apr 29, 2:46 PM EDT | Fire Weather Watch | RNK | 16 hr |
| Apr 30, 6:41 AM EDT | Red Flag Warning | RNK | 13 hr |
| May 3, 2:12 PM EDT | Special Weather Statement | RNK | 33 min |
| May 4, 1:04 PM EDT | Mesoscale Discussion | SPC | 56 min |
| May 4, 3:55 PM EDT | Special Weather Statement | RNK | 35 min |
| May 4, 4:16 PM EDT | Mesoscale Discussion | SPC | 119 min |
| May 7, 11:57 AM EDT | Special Weather Statement | RNK | 33 min |
| May 10, 12:51 PM EDT | Mesoscale Discussion | SPC | 114 min |
| May 24, 1:57 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| May 28, 5:21 PM EDT | Special Weather Statement | RNK | 39 min |
| May 29, 3:03 PM EDT | Special Weather Statement | RNK | 27 min |
| Jun 10, 8:12 PM EDT | Areal Flood Advisory | RNK | 111 min |
| Jun 11, 1:24 PM EDT | Special Weather Statement | RNK | 51 min |
| Jun 11, 1:46 PM EDT | Severe Thunderstorm Warning | RNK | 40 min |
| Jun 11, 2:12 PM EDT | Flash Flood Warning | RNK | 112 min |
| Jun 11, 2:38 PM EDT | Special Weather Statement | RNK | 37 min |
| Jun 22, 12:11 PM EDT | Special Weather Statement | RNK | 34 min |
| Jul 1, 11:17 PM EDT | Special Weather Statement | RNK | 28 min |
| Jul 7, 3:02 PM EDT | Flash Flood Watch | RNK | 28 hr |
| Jul 11, 1:27 PM EDT | Special Weather Statement | RNK | 48 min |
| Jul 11, 1:38 PM EDT | Severe Thunderstorm Warning | RNK | 67 min |
| Jul 11, 2:18 PM EDT | Special Weather Statement | RNK | 27 min |
| Jul 11, 2:46 PM EDT | Severe Thunderstorm Warning | RNK | 31 min |
| Jul 11, 3:29 PM EDT | Areal Flood Advisory | RNK | 87 min |
| Jul 14, 2:57 PM EDT | Special Weather Statement | RAH | 63 min |
| Jul 14, 4:40 PM EDT | Special Weather Statement | RNK | 35 min |
| Jul 17, 1:15 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 17, 2:49 PM EDT | Special Weather Statement | RNK | 26 min |
| Jul 17, 2:56 PM EDT | Severe Thunderstorm Warning | RNK | 49 min |
| Jul 17, 3:42 PM EDT | Special Weather Statement | RNK | 48 min |
| Jul 17, 3:48 PM EDT | Severe Thunderstorm Warning | RNK | 57 min |
| Jul 17, 3:52 PM EDT | Areal Flood Advisory | RNK | 3 hr |
| Jul 17, 4:00 PM EDT | Severe Thunderstorm Warning | RNK | 60 min |
| Jul 17, 4:11 PM EDT | Flash Flood Warning | RNK | 3 hr |
| Jul 17, 5:00 PM EDT | Severe Thunderstorm Warning | RNK | 60 min |
| Jul 17, 6:02 PM EDT | Special Weather Statement | RNK | 13 min |
| Jul 17, 6:50 PM EDT | Areal Flood Advisory | RNK | 7 hr |
| Jul 17, 9:18 PM EDT | Severe Thunderstorm Warning | RNK | 57 min |
| Jul 17, 10:04 PM EDT | Severe Thunderstorm Warning | RNK | 56 min |
| Jul 18, 4:53 PM EDT | Special Weather Statement | RNK | 37 min |
| Jul 26, 12:58 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 26, 1:39 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 26, 3:29 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 26, 7:08 PM EDT | Special Weather Statement | RNK | 52 min |
| Aug 1, 6:29 AM EDT | Mesoscale Discussion | SPC | 91 min |
| Aug 8, 2:01 AM EDT | Dense Fog Advisory | RNK | 7 hr |
| Aug 10, 5:49 PM EDT | Special Weather Statement | RNK | 26 min |
| Aug 10, 6:12 PM EDT | Special Weather Statement | RNK | 48 min |
| Aug 13, 9:12 PM EDT | Special Weather Statement | RNK | 33 min |
| Aug 13, 9:46 PM EDT | Special Weather Statement | RNK | 44 min |
| Aug 14, 1:10 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 14, 5:12 PM EDT | Special Weather Statement | RNK | 33 min |
| Aug 15, 4:07 PM EDT | Special Weather Statement | RNK | 38 min |
| Aug 15, 4:28 PM EDT | Severe Thunderstorm Warning | RNK | 62 min |
| Aug 17, 1:58 PM EDT | Special Weather Statement | RNK | 32 min |
| Aug 17, 2:18 PM EDT | Tornado Warning | RNK | 32 min |
| Aug 17, 6:28 PM EDT | Tornado Watch | SPC | 10 hr |
| Aug 31, 7:36 PM EDT | Tornado Watch | SPC | 7 hr |
| Sep 8, 10:00 AM EDT | Special Weather Statement | RNK | 60 min |
| Sep 16, 4:38 PM EDT | Special Weather Statement | RNK | 52 min |
| Sep 22, 2:44 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 4, 2:01 PM EDT | Special Weather Statement | RNK | 59 min |
| Oct 25, 3:01 PM EDT | Mesoscale Discussion | SPC | 119 min |
| Oct 25, 6:26 PM EDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Oct 25, 7:58 PM EDT | Special Weather Statement | RNK | 17 min |
| Oct 25, 8:13 PM EDT | Mesoscale Discussion | SPC | 92 min |
| Oct 25, 8:16 PM EDT | Severe Thunderstorm Warning | RNK | 29 min |
| Nov 3, 1:50 PM EDT | Freeze Watch | RNK | 14 hr |
| Nov 4, 4:02 AM EDT | Freeze Warning | RNK | 30 hr |
| Dec 11, 5:00 PM EST | Special Weather Statement | RNK | 30 min |
| Dec 11, 5:30 PM EST | Special Weather Statement | RNK | 30 min |
| Dec 11, 6:01 PM EST | Special Weather Statement | RNK | 29 min |
| Dec 18, 4:01 AM EST | Dense Fog Advisory | RNK | 6 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 | 12 |
| Tornado Warning | 3 |
| Severe Thunderstorm Watch | 4 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 21 |
| Special Weather Statement | 43 |
| Flooding | |
| Flash Flood Warning | 2 |
| Flash Flood Watch | 1 |
| Areal Flood Advisory | 4 |
| Winter | |
| Winter Storm Warning | 3 |
| Winter Storm Watch | 3 |
| Winter Weather Advisory | 7 |
| Cold | |
| Freeze Warning | 3 |
| Freeze Watch | 2 |
| Fire | |
| Red Flag Warning | 2 |
| Fire Weather Watch | 2 |
| Fog and smoke | |
| Dense Fog Advisory | 7 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20202022
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.