Alert archive / North Carolina / Chatham County
Weather alerts in Chatham County, North Carolina, 2021
136 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Chatham County and its neighbors
Each county as a circle sized by its count in 2021. Tap one for its archive.
- Alerts
- 136
- Warnings
- 37
- Watches
- 10
- Advisories
- 37
- Busiest month
- August26 alerts
- Busiest day
- May 10, 20218 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
1 of 1 tornado warnings covering Chatham County in 2021 had a tornado report inside them.
Chatham County, 2021
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 1 | 0% | 0 | ||
| Severe thunderstorm warnings | 23 | 15 | 35% | 11 | 73% | 19 min |
| Flash flood warnings | 4 | 2 | 50% | 1 | 100% | 73 min |
Each office's whole area, 2021
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Raleigh, NC: tornado warnings | 22 | 4 | 82% | 4 | 100% | 5 min |
| NWS Raleigh, NC: severe thunderstorm warnings | 138 | 84 | 39% | 237 | 81% | 19 min |
| NWS Raleigh, NC: flash flood warnings | 27 | 14 | 48% | 36 | 67% | 100 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 1, 7:45 PM EST | Special Weather Statement | RAH | 60 min |
| Jan 1, 9:47 PM EST | Areal Flood Advisory | RAH | 58 min |
| Jan 2, 8:15 AM EST | Dense Fog Advisory | RAH | 3 hr |
| Jan 3, 9:36 AM EST | River Flood Warning | RAH | 11 hr |
| Jan 7, 3:36 PM EST | Winter Weather Advisory | RAH | 30 hr |
| Jan 16, 1:27 AM EST | Dense Fog Advisory | RAH | 8 hr |
| Jan 27, 3:18 AM EST | Winter Weather Advisory | RAH | 29 hr |
| Jan 30, 4:10 AM EST | Winter Weather Advisory | RAH | 34 hr |
| Feb 11, 3:54 PM EST | Winter Weather Advisory | RAH | 68 hr |
| Feb 13, 7:57 PM EST | River Flood Warning | RAH | 16 hr |
| Feb 16, 4:54 AM EST | River Flood Warning | RAH | 21 hr |
| Feb 17, 3:13 AM EST | Winter Weather Advisory | RAH | 52 hr |
| Feb 22, 11:53 PM EST | Dense Fog Advisory | RAH | 9 hr |
| Mar 18, 4:45 PM EDT | Tornado Watch | SPC | 4 hr |
| Mar 18, 5:13 PM EDT | Severe Thunderstorm Warning | RAH | 62 min |
| Mar 18, 5:57 PM EDT | Mesoscale Discussion | SPC | 63 min |
| Mar 18, 6:59 PM EDT | Severe Thunderstorm Warning | RAH | 21 min |
| Mar 18, 7:49 PM EDT | Mesoscale Discussion | SPC | 56 min |
| Mar 26, 10:32 AM EDT | Special Weather Statement | RAH | 43 min |
| Mar 26, 10:46 AM EDT | Severe Thunderstorm Warning | RAH | 44 min |
| Mar 27, 6:39 AM EDT | Dense Fog Advisory | RAH | 3 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, 4:12 PM EDT | Severe Thunderstorm Warning | RAH | 48 min |
| Mar 27, 4:26 PM EDT | Severe Thunderstorm Warning | RAH | 64 min |
| Mar 27, 4:42 PM EDT | Severe Thunderstorm Warning | RAH | 48 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, 2:45 PM EDT | Severe Thunderstorm Warning | RAH | 30 min |
| Mar 28, 8:06 PM EDT | Special Weather Statement | RAH | 54 min |
| Mar 29, 3:26 AM EDT | Frost Advisory | RAH | 29 hr |
| Mar 31, 2:22 PM EDT | Mesoscale Discussion | SPC | 113 min |
| Mar 31, 2:34 PM EDT | Freeze Watch | RAH | 13 hr |
| Mar 31, 3:19 PM EDT | Special Weather Statement | RAH | 56 min |
| Mar 31, 4:18 PM EDT | Special Weather Statement | RAH | 57 min |
| Mar 31, 4:33 PM EDT | Severe Thunderstorm Warning | RAH | 42 min |
| Apr 1, 3:49 AM EDT | Freeze Warning | RAH | 29 hr |
| Apr 2, 9:02 AM EDT | Hard Freeze Warning | RAH | 24 hr |
| Apr 3, 9:43 AM EDT | Frost Advisory | RAH | 23 hr |
| Apr 10, 11:31 PM EDT | Special Weather Statement | RAH | 59 min |
| Apr 10, 11:45 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 20, 3:16 PM EDT | Fire Weather Watch | RAH | 12 hr |
| Apr 21, 3:22 AM EDT | Red Flag Warning | RAH | 17 hr |
| Apr 21, 10:58 AM EDT | Freeze Warning | RAH | 21 hr |
| Apr 22, 10:45 AM EDT | Frost Advisory | RAH | 22 hr |
| Apr 29, 2:26 PM EDT | Fire Weather Watch | RAH | 13 hr |
| Apr 30, 3:25 AM EDT | Red Flag Warning | RAH | 16 hr |
| May 4, 4:16 PM EDT | Mesoscale Discussion | SPC | 119 min |
| May 4, 4:58 PM EDT | Special Weather Statement | RAH | 62 min |
| May 5, 8:00 PM EDT | Special Weather Statement | RAH | 60 min |
| May 7, 2:18 PM EDT | Special Weather Statement | RAH | 42 min |
| May 10, 12:51 PM EDT | Mesoscale Discussion | SPC | 114 min |
| May 10, 3:47 PM EDT | Severe Thunderstorm Warning | RAH | 43 min |
| May 10, 3:57 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 10, 4:32 PM EDT | Special Weather Statement | RAH | 43 min |
| May 10, 4:37 PM EDT | Severe Thunderstorm Warning | RAH | 38 min |
| May 10, 4:45 PM EDT | Tornado Warning | RAH | 30 min |
| May 10, 5:14 PM EDT | Severe Thunderstorm Warning | RAH | 46 min |
| May 10, 5:47 PM EDT | Special Weather Statement | RAH | 43 min |
| May 10, 8:17 PM EDT | Mesoscale Discussion | SPC | 58 min |
| May 28, 6:23 PM EDT | Special Weather Statement | RAH | 52 min |
| May 29, 12:37 PM EDT | Mesoscale Discussion | SPC | 113 min |
| Jun 2, 3:11 PM EDT | Special Weather Statement | RAH | 64 min |
| Jun 2, 4:11 PM EDT | Areal Flood Advisory | RAH | 49 min |
| Jun 3, 3:02 AM EDT | Areal Flood Advisory | RAH | 3 hr |
| Jun 3, 3:23 AM EDT | Flash Flood Watch | RAH | 24 hr |
| Jun 3, 2:39 PM EDT | Special Weather Statement | RAH | 51 min |
| Jun 3, 3:17 PM EDT | Areal Flood Advisory | RAH | 118 min |
| Jun 3, 4:27 PM EDT | Flash Flood Warning | RAH | 112 min |
| Jun 10, 1:50 AM EDT | Areal Flood Advisory | RAH | 3 hr |
| Jun 10, 6:07 PM EDT | Special Weather Statement | RAH | 53 min |
| Jun 12, 12:07 AM EDT | Areal Flood Advisory | RAH | 104 min |
| Jun 22, 12:13 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 26, 4:40 PM EDT | Areal Flood Advisory | RAH | 88 min |
| Jun 26, 6:59 PM EDT | Special Weather Statement | RAH | 46 min |
| Jul 1, 9:38 PM EDT | Severe Thunderstorm Warning | RAH | 52 min |
| Jul 7, 3:01 PM EDT | Flash Flood Watch | RAH | 27 hr |
| Jul 9, 4:25 PM EDT | Special Weather Statement | RAH | 65 min |
| Jul 9, 4:45 PM EDT | Severe Thunderstorm Warning | RAH | 45 min |
| Jul 13, 6:57 PM EDT | Special Weather Statement | RAH | 33 min |
| Jul 17, 1:15 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 18, 7:35 PM EDT | Special Weather Statement | RAH | 55 min |
| Jul 18, 8:33 PM EDT | Special Weather Statement | RAH | 57 min |
| Jul 18, 8:42 PM EDT | Areal Flood Advisory | RAH | 3 hr |
| Jul 19, 12:19 PM EDT | Areal Flood Advisory | RAH | 3 hr |
| Jul 26, 12:58 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 28, 3:36 PM EDT | Severe Thunderstorm Warning | RAH | 39 min |
| Jul 29, 3:39 PM EDT | Heat Advisory | RAH | 27 hr |
| Aug 1, 6:29 AM EDT | Mesoscale Discussion | SPC | 91 min |
| Aug 1, 12:37 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 1, 2:07 PM EDT | Special Weather Statement | RAH | 53 min |
| Aug 1, 2:42 PM EDT | Severe Thunderstorm Warning | RAH | 48 min |
| Aug 1, 2:53 PM EDT | Mesoscale Discussion | SPC | 97 min |
| Aug 8, 2:02 AM EDT | Dense Fog Advisory | RAH | 7 hr |
| Aug 10, 2:41 PM EDT | Heat Advisory | RAH | 28 hr |
| Aug 12, 3:30 PM EDT | Heat Advisory | RAH | 28 hr |
| Aug 14, 4:01 AM EDT | Heat Advisory | RAH | 14 hr |
| Aug 14, 1:10 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 14, 3:25 PM EDT | Flash Flood Warning | RAH | 3 hr |
| Aug 14, 3:27 PM EDT | Severe Thunderstorm Warning | RAH | 37 min |
| Aug 14, 3:39 PM EDT | Severe Thunderstorm Warning | RAH | 51 min |
| Aug 15, 2:49 PM EDT | Special Weather Statement | RAH | 41 min |
| Aug 15, 5:44 PM EDT | Areal Flood Advisory | RAH | 93 min |
| Aug 16, 4:45 PM EDT | Areal Flood Advisory | RAH | 2 hr |
| Aug 16, 5:07 PM EDT | Special Weather Statement | RAH | 38 min |
| Aug 17, 2:08 PM EDT | Special Weather Statement | RAH | 52 min |
| Aug 18, 2:58 AM EDT | Severe Thunderstorm Warning | RAH | 47 min |
| Aug 18, 5:04 AM EDT | Special Weather Statement | RAH | 41 min |
| Aug 19, 8:42 PM EDT | Severe Thunderstorm Warning | RAH | 63 min |
| Aug 19, 10:21 PM EDT | Special Weather Statement | RAH | 54 min |
| Aug 20, 8:21 PM EDT | Special Weather Statement | RAH | 54 min |
| Aug 20, 8:26 PM EDT | Severe Thunderstorm Warning | RAH | 64 min |
| Aug 22, 5:07 PM EDT | Special Weather Statement | RAH | 38 min |
| Aug 23, 3:53 AM EDT | Dense Fog Advisory | RAH | 5 hr |
| Sep 1, 6:49 PM EDT | Special Weather Statement | RAH | 41 min |
| Sep 1, 7:56 PM EDT | Special Weather Statement | RAH | 34 min |
| Sep 22, 9:45 AM EDT | Areal Flood Advisory | RAH | 3 hr |
| Sep 22, 2:44 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Sep 22, 3:17 PM EDT | Areal Flood Advisory | RAH | 118 min |
| Sep 22, 5:16 PM EDT | Special Weather Statement | RAH | 59 min |
| Sep 22, 10:06 PM EDT | Flash Flood Warning | RAH | 2 hr |
| Oct 9, 2:10 AM EDT | Areal Flood Advisory | RAH | 3 hr |
| Oct 9, 3:47 AM EDT | Flash Flood Warning | RAH | 2 hr |
| Oct 9, 4:34 AM EDT | Areal Flood Advisory | RAH | 3 hr |
| Oct 16, 2:35 PM EDT | Special Weather Statement | RAH | 55 min |
| Oct 25, 3:01 PM EDT | Mesoscale Discussion | SPC | 119 min |
| Oct 25, 8:37 PM EDT | Severe Thunderstorm Warning | RAH | 38 min |
| Oct 25, 10:19 PM EDT | Areal Flood Advisory | RAH | 2 hr |
| Nov 3, 2:19 PM EDT | Freeze Watch | RAH | 13 hr |
| Nov 4, 3:13 AM EDT | Frost Advisory | RAH | 30 hr |
| Nov 4, 3:13 AM EDT | Freeze Warning | RAH | 30 hr |
| Dec 11, 6:13 PM EST | Severe Thunderstorm Warning | RAH | 47 min |
| Dec 11, 6:30 PM EST | Severe Thunderstorm Warning | RAH | 45 min |
| Dec 11, 7:02 PM EST | Special Weather Statement | RAH | 43 min |
| Dec 18, 3:28 AM EST | Dense Fog Advisory | RAH | 6 hr |
| Dec 25, 3:23 AM EST | Wind Advisory | RAH | 13 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 | 23 |
| Tornado Warning | 1 |
| Severe Thunderstorm Watch | 3 |
| Tornado Watch | 1 |
| Mesoscale Discussion | 19 |
| Special Weather Statement | 33 |
| Flooding | |
| Flash Flood Warning | 4 |
| River Flood Warning | 3 |
| Flash Flood Watch | 2 |
| Areal Flood Advisory | 16 |
| Winter | |
| Winter Weather Advisory | 5 |
| Heat | |
| Heat Advisory | 4 |
| Cold | |
| Freeze Warning | 3 |
| Hard Freeze Warning | 1 |
| Freeze Watch | 2 |
| Frost Advisory | 4 |
| Wind and dust | |
| Wind Advisory | 1 |
| 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.