Alert archive / Tennessee / Williamson County
Weather alerts in Williamson County, Tennessee, 2019
163 weather alerts in 2019, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Williamson County and its neighbors
Each county as a circle sized by its count in 2019. Tap one for its archive.
- Alerts
- 163
- Warnings
- 40
- Watches
- 13
- Advisories
- 59
- Busiest month
- August34 alerts
- Busiest day
- August 13, 201914 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 Williamson County in 2019 had a tornado report inside them.
Williamson County, 2019
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 3 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 23 | 18 | 22% | 23 | 78% | 16 min |
| Flash flood warnings | 11 | 10 | 9% | 6 | 67% | 36 min |
Each office's whole area, 2019
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Nashville, TN: tornado warnings | 17 | 0 | 100% | 7 | 0% | |
| NWS Nashville, TN: severe thunderstorm warnings | 137 | 83 | 39% | 311 | 71% | 20 min |
| NWS Nashville, TN: flash flood warnings | 63 | 45 | 29% | 178 | 79% | 92 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, Central Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jan 1, 1:49 PM CST | River Flood Advisory | OHX | 3 hr |
| Jan 20, 12:57 AM CST | River Flood Advisory | OHX | 11 hr |
| Jan 21, 2:47 PM CST | Wind Advisory | OHX | 48 hr |
| Jan 27, 2:06 PM CST | Winter Weather Advisory | OHX | 37 hr |
| Feb 6, 3:02 PM CST | Mesoscale Discussion | SPC | 118 min |
| Feb 6, 3:30 PM CST | Areal Flood Advisory | OHX | 4 hr |
| Feb 6, 3:37 PM CST | Areal Flood Advisory | OHX | 4 hr |
| Feb 6, 4:10 PM CST | Areal Flood Advisory | OHX | 4 hr |
| Feb 6, 7:45 PM CST | Flash Flood Warning | OHX | 4 hr |
| Feb 6, 7:48 PM CST | Special Weather Statement | OHX | 42 min |
| Feb 6, 7:58 PM CST | Tornado Warning | OHX | 32 min |
| Feb 6, 9:31 PM CST | Areal Flood Advisory | OHX | 12 hr |
| Feb 6, 11:27 PM CST | Flash Flood Warning | OHX | 9 hr |
| Feb 7, 9:49 AM CST | Wind Advisory | OHX | 9 hr |
| Feb 12, 3:26 AM CST | Special Weather Statement | OHX | 34 min |
| Feb 12, 12:23 PM CST | Special Weather Statement | OHX | 67 min |
| Feb 18, 1:51 PM CST | Flash Flood Watch | OHX | 52 hr |
| Feb 20, 4:55 AM CST | Areal Flood Advisory | OHX | 3 hr |
| Feb 20, 6:58 AM CST | Special Weather Statement | OHX | 32 min |
| Feb 20, 7:37 AM CST | Flash Flood Warning | OHX | 6 hr |
| Feb 20, 7:57 AM CST | Areal Flood Advisory | OHX | 8 hr |
| Feb 20, 8:58 AM CST | Flash Flood Warning | OHX | 5 hr |
| Feb 20, 1:43 PM CST | River Flood Advisory | OHX | 69 hr |
| Feb 20, 5:20 PM CST | River Flood Advisory | OHX | 17 hr |
| Feb 20, 9:24 PM CST | River Flood Advisory | OHX | 15 hr |
| Feb 21, 1:48 AM CST | Flash Flood Watch | OHX | 70 hr |
| Feb 22, 10:26 AM CST | Areal Flood Advisory | OHX | 5 hr |
| Feb 22, 2:22 PM CST | Areal Flood Advisory | OHX | 10 hr |
| Feb 23, 9:55 AM CST | Flash Flood Warning | OHX | 3 hr |
| Feb 23, 11:00 AM CST | River Flood Warning | OHX | 33 hr |
| Feb 23, 12:42 PM CST | Areal Flood Advisory | OHX | 3 hr |
| Feb 23, 3:01 PM CST | Tornado Watch | SPC | 6 hr |
| Feb 23, 5:13 PM CST | River Flood Advisory | OHX | 24 hr |
| Feb 23, 5:48 PM CST | Flash Flood Warning | OHX | 4 hr |
| Feb 23, 6:25 PM CST | Flash Flood Warning | OHX | 4 hr |
| Feb 23, 7:28 PM CST | River Flood Advisory | OHX | 21 hr |
| Feb 24, 3:44 AM CST | River Flood Advisory | OHX | 24 hr |
| Mar 8, 2:02 PM CST | Wind Advisory | OHX | 31 hr |
| Mar 9, 1:27 PM CST | Mesoscale Discussion | SPC | 2 hr |
| Mar 9, 2:16 PM CST | Tornado Watch | SPC | 7 hr |
| Mar 9, 5:27 PM CST | Special Weather Statement | OHX | 33 min |
| Mar 9, 5:54 PM CST | Areal Flood Advisory | OHX | 111 min |
| Mar 9, 6:12 PM CST | Special Weather Statement | OHX | 63 min |
| Mar 9, 6:53 PM CST | Severe Thunderstorm Warning | OHX | 37 min |
| Mar 10, 6:47 AM CDT | River Flood Advisory | OHX | 12 hr |
| Mar 13, 3:17 PM CDT | Wind Advisory | OHX | 28 hr |
| Mar 14, 11:47 AM CDT | Mesoscale Discussion | SPC | 88 min |
| Mar 14, 12:11 PM CDT | Tornado Watch | SPC | 7 hr |
| Mar 14, 2:35 PM CDT | Special Weather Statement | OHX | 25 min |
| Mar 14, 2:58 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Mar 30, 3:54 AM CDT | Freeze Watch | OHX | 23 hr |
| Mar 30, 3:52 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Mar 30, 6:04 PM CDT | Severe Thunderstorm Warning | OHX | 41 min |
| Mar 30, 6:14 PM CDT | Severe Thunderstorm Warning | OHX | 31 min |
| Mar 30, 6:32 PM CDT | Tornado Warning | OHX | 28 min |
| Mar 30, 6:54 PM CDT | Tornado Warning | OHX | 21 min |
| Mar 31, 2:36 AM CDT | Freeze Warning | OHX | 30 hr |
| Apr 7, 3:42 PM CDT | Special Weather Statement | OHX | 48 min |
| Apr 7, 3:48 PM CDT | Severe Thunderstorm Warning | OHX | 27 min |
| Apr 7, 4:15 PM CDT | Special Weather Statement | OHX | 30 min |
| Apr 9, 5:38 AM CDT | Dense Fog Advisory | OHX | 4 hr |
| Apr 10, 2:32 PM CDT | Wind Advisory | OHX | 30 hr |
| Apr 13, 9:23 PM CDT | Severe Thunderstorm Warning | OHX | 37 min |
| Apr 14, 2:22 AM CDT | Wind Advisory | OHX | 17 hr |
| Apr 21, 2:05 AM CDT | Dense Fog Advisory | OHX | 7 hr |
| May 1, 5:22 PM CDT | Special Weather Statement | OHX | 38 min |
| May 2, 12:03 PM CDT | Severe Thunderstorm Warning | OHX | 16 min |
| Jun 9, 7:04 PM CDT | Areal Flood Advisory | OHX | 116 min |
| Jun 19, 12:35 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Jun 19, 5:31 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 19, 6:55 PM CDT | Severe Thunderstorm Warning | OHX | 35 min |
| Jun 19, 7:27 PM CDT | Special Weather Statement | OHX | 33 min |
| Jun 19, 7:34 PM CDT | Severe Thunderstorm Warning | OHX | 26 min |
| Jun 19, 7:45 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 19, 7:58 PM CDT | Severe Thunderstorm Warning | OHX | 62 min |
| Jun 20, 2:46 AM CDT | Special Weather Statement | OHX | 44 min |
| Jun 20, 3:03 AM CDT | Severe Thunderstorm Warning | OHX | 27 min |
| Jun 20, 3:28 AM CDT | Severe Thunderstorm Warning | OHX | 20 min |
| Jun 21, 5:14 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Jun 21, 5:47 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 21, 7:29 PM CDT | Severe Thunderstorm Warning | OHX | 46 min |
| Jun 21, 7:58 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Jun 21, 8:05 PM CDT | Severe Thunderstorm Warning | OHX | 40 min |
| Jun 22, 8:44 AM CDT | Special Weather Statement | OHX | 46 min |
| Jun 22, 4:52 PM CDT | Severe Thunderstorm Warning | OHX | 38 min |
| Jun 23, 5:36 PM CDT | Severe Thunderstorm Watch | SPC | 3 hr |
| Jun 24, 5:00 AM CDT | Special Weather Statement | OHX | 30 min |
| Jun 26, 7:01 PM CDT | Special Weather Statement | OHX | 44 min |
| Jun 27, 4:22 PM CDT | Special Weather Statement | OHX | 38 min |
| Jun 27, 4:59 PM CDT | Severe Thunderstorm Warning | OHX | 14 min |
| Jun 27, 5:15 PM CDT | Flash Flood Warning | OHX | 62 min |
| Jun 27, 5:33 PM CDT | Severe Thunderstorm Warning | OHX | 42 min |
| Jun 27, 5:44 PM CDT | Areal Flood Advisory | OHX | 2 hr |
| Jul 6, 3:33 PM CDT | Special Weather Statement | OHX | 42 min |
| Jul 10, 2:25 PM CDT | Areal Flood Advisory | OHX | 3 hr |
| Jul 10, 4:04 PM CDT | Special Weather Statement | OHX | 26 min |
| Jul 16, 1:34 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 17, 11:30 PM CDT | Special Weather Statement | OHX | 45 min |
| Jul 18, 4:08 AM CDT | Heat Advisory | OHX | 10 hr |
| Jul 18, 2:29 PM CDT | Heat Advisory | OHX | 29 hr |
| Jul 20, 7:15 PM CDT | Areal Flood Advisory | OHX | 2 hr |
| Jul 22, 3:19 AM CDT | Flash Flood Watch | OHX | 17 hr |
| Jul 22, 2:08 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 22, 3:26 PM CDT | Flash Flood Warning | OHX | 3 hr |
| Jul 22, 3:57 PM CDT | Flash Flood Warning | OHX | 3 hr |
| Jul 30, 6:14 PM CDT | Areal Flood Advisory | OHX | 2 hr |
| Aug 1, 8:14 PM CDT | Areal Flood Advisory | OHX | 61 min |
| Aug 2, 8:29 PM CDT | Areal Flood Advisory | OHX | 3 hr |
| Aug 2, 8:32 PM CDT | Special Weather Statement | OHX | 43 min |
| Aug 2, 9:14 PM CDT | Special Weather Statement | OHX | 31 min |
| Aug 2, 9:46 PM CDT | Special Weather Statement | OHX | 44 min |
| Aug 3, 5:46 PM CDT | Special Weather Statement | OHX | 44 min |
| Aug 3, 6:02 PM CDT | Areal Flood Advisory | OHX | 118 min |
| Aug 4, 2:49 PM CDT | Special Weather Statement | OHX | 26 min |
| Aug 4, 3:06 PM CDT | Areal Flood Advisory | OHX | 114 min |
| Aug 4, 3:12 PM CDT | Special Weather Statement | OHX | 33 min |
| Aug 4, 3:53 PM CDT | Special Weather Statement | OHX | 37 min |
| Aug 5, 12:31 AM CDT | Dense Fog Advisory | OHX | 8 hr |
| Aug 6, 8:19 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Aug 6, 8:34 PM CDT | Severe Thunderstorm Warning | OHX | 41 min |
| Aug 6, 8:37 PM CDT | Special Weather Statement | OHX | 53 min |
| Aug 6, 9:07 PM CDT | Severe Thunderstorm Warning | OHX | 38 min |
| Aug 8, 3:33 AM CDT | Dense Fog Advisory | OHX | 5 hr |
| Aug 12, 2:05 PM CDT | Heat Advisory | OHX | 29 hr |
| Aug 13, 1:58 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 13, 2:49 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 13, 3:20 PM CDT | Areal Flood Advisory | OHX | 55 min |
| Aug 13, 3:35 PM CDT | Severe Thunderstorm Warning | OHX | 25 min |
| Aug 13, 3:54 PM CDT | Special Weather Statement | OHX | 51 min |
| Aug 13, 4:00 PM CDT | Severe Thunderstorm Warning | OHX | 45 min |
| Aug 13, 4:06 PM CDT | Severe Thunderstorm Warning | OHX | 24 min |
| Aug 13, 4:44 PM CDT | Special Weather Statement | OHX | 31 min |
| Aug 13, 4:46 PM CDT | Severe Thunderstorm Warning | OHX | 14 min |
| Aug 13, 5:09 PM CDT | Mesoscale Discussion | SPC | 66 min |
| Aug 13, 5:20 PM CDT | Special Weather Statement | OHX | 40 min |
| Aug 13, 5:34 PM CDT | Areal Flood Advisory | OHX | 116 min |
| Aug 13, 5:45 PM CDT | Flash Flood Warning | OHX | 2 hr |
| Aug 13, 6:55 PM CDT | Mesoscale Discussion | SPC | 65 min |
| Aug 20, 5:06 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Aug 23, 1:13 AM CDT | Dense Fog Advisory | OHX | 6 hr |
| Sep 10, 4:09 PM CDT | Special Weather Statement | OHX | 21 min |
| Sep 10, 4:32 PM CDT | Special Weather Statement | OHX | 28 min |
| Sep 10, 4:41 PM CDT | Severe Thunderstorm Warning | OHX | 34 min |
| Sep 27, 12:49 AM CDT | Dense Fog Advisory | OHX | 8 hr |
| Oct 6, 8:46 PM CDT | Special Weather Statement | OHX | 59 min |
| Oct 21, 12:57 PM CDT | Special Weather Statement | OHX | 33 min |
| Oct 26, 3:18 AM CDT | Wind Advisory | OHX | 15 hr |
| Oct 28, 2:04 AM CDT | Dense Fog Advisory | OHX | 7 hr |
| Oct 28, 9:44 PM CDT | Dense Fog Advisory | OHX | 11 hr |
| Oct 30, 2:02 PM CDT | Freeze Watch | OHX | 13 hr |
| Oct 31, 2:37 AM CDT | Freeze Warning | OHX | 30 hr |
| Nov 1, 6:50 AM CDT | Freezing Fog Advisory | OHX | 2 hr |
| Nov 26, 12:26 PM CST | Wind Advisory | OHX | 24 hr |
| Dec 1, 2:04 PM CST | River Flood Advisory | OHX | 6 hr |
| Dec 16, 7:39 AM CST | Flash Flood Watch | OHX | 12 hr |
| Dec 28, 12:24 AM CST | Dense Fog Advisory | OHX | 4 hr |
| Dec 29, 3:02 PM CST | Special Weather Statement | OHX | 43 min |
| Dec 29, 5:06 PM CST | Areal Flood Advisory | OHX | 114 min |
| Dec 29, 5:49 PM CST | Areal Flood Advisory | OHX | 3 hr |
| Dec 29, 6:57 PM CST | Areal Flood Advisory | OHX | 3 hr |
| Dec 30, 2:50 AM CST | River Flood Advisory | OHX | 26 hr |
| Dec 30, 6:48 AM CST | River Flood Advisory | OHX | 11 hr |
| Dec 30, 10:22 AM CST | River Flood Advisory | OHX | 7 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 | 3 |
| Severe Thunderstorm Watch | 4 |
| Tornado Watch | 3 |
| Mesoscale Discussion | 16 |
| Special Weather Statement | 35 |
| Flooding | |
| Flash Flood Warning | 11 |
| River Flood Warning | 1 |
| Flash Flood Watch | 4 |
| Areal Flood Advisory | 24 |
| River Flood Advisory | 13 |
| Winter | |
| Winter Weather Advisory | 1 |
| Heat | |
| Heat Advisory | 3 |
| Cold | |
| Freeze Warning | 2 |
| Freeze Watch | 2 |
| Wind and dust | |
| Wind Advisory | 8 |
| Fog and smoke | |
| Dense Fog Advisory | 9 |
| Freezing Fog Advisory | 1 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20182020
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.