Alert archive / Tennessee / Knox County
Weather alerts in Knox County, Tennessee, 2020
127 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Knox County and its neighbors
Each county as a circle sized by its count in 2020. Tap one for its archive.
- Alerts
- 127
- Warnings
- 30
- Watches
- 11
- Advisories
- 41
- Busiest month
- July24 alerts
- Busiest day
- January 11, 20206 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 1 tornado warnings covering Knox County in 2020 had a tornado report inside them.
Knox County, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 19 | 17 | 11% | 21 | 71% | 18 min |
| Flash flood warnings | 4 | 3 | 25% | 3 | 100% | 38 min |
Each office's whole area, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Morristown, TN: tornado warnings | 13 | 5 | 62% | 6 | 83% | 6 min |
| NWS Morristown, TN: severe thunderstorm warnings | 158 | 129 | 18% | 243 | 81% | 21 min |
| NWS Morristown, TN: flash flood warnings | 22 | 18 | 18% | 33 | 82% | 42 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, 3:26 AM EST | Flood Watch | MRX | 64 hr |
| Jan 2, 11:34 PM EST | Areal Flood Advisory | MRX | 5 hr |
| Jan 3, 4:56 AM EST | Areal Flood Advisory | MRX | 4 hr |
| Jan 10, 2:39 PM EST | Wind Advisory | MRX | 34 hr |
| Jan 11, 1:42 PM EST | Tornado Watch | SPC | 7 hr |
| Jan 11, 4:16 PM EST | Mesoscale Discussion | SPC | 89 min |
| Jan 11, 4:50 PM EST | Severe Thunderstorm Warning | MRX | 40 min |
| Jan 11, 4:56 PM EST | Severe Thunderstorm Warning | MRX | 49 min |
| Jan 11, 5:23 PM EST | Severe Thunderstorm Warning | MRX | 52 min |
| Jan 11, 5:37 PM EST | Severe Thunderstorm Warning | MRX | 53 min |
| Feb 4, 3:46 PM EST | Flash Flood Watch | MRX | 47 hr |
| Feb 5, 9:51 PM EST | Special Weather Statement | MRX | 39 min |
| Feb 5, 10:20 PM EST | Areal Flood Advisory | MRX | 5 hr |
| Feb 5, 10:31 PM EST | Special Weather Statement | MRX | 44 min |
| Feb 6, 3:15 AM EST | Areal Flood Warning | MRX | 6 hr |
| Feb 6, 9:03 AM EST | Areal Flood Warning | MRX | 12 hr |
| Feb 6, 8:41 PM EST | Areal Flood Warning | MRX | 15 hr |
| Feb 9, 3:35 AM EST | Flood Watch | MRX | 36 hr |
| Feb 10, 3:14 PM EST | Flash Flood Watch | MRX | 24 hr |
| Feb 12, 3:03 AM EST | Flash Flood Watch | MRX | 31 hr |
| Feb 12, 8:37 PM EST | Mesoscale Discussion | SPC | 83 min |
| Feb 12, 9:22 PM EST | Severe Thunderstorm Warning | MRX | 53 min |
| Mar 3, 4:28 AM EST | Special Weather Statement | MRX | 47 min |
| Mar 3, 4:35 AM EST | Tornado Warning | MRX | 25 min |
| Mar 3, 5:19 AM EST | Special Weather Statement | MRX | 41 min |
| Mar 3, 5:42 AM EST | Areal Flood Advisory | MRX | 3 hr |
| Mar 3, 6:02 AM EST | Special Weather Statement | MRX | 43 min |
| Mar 3, 6:36 AM EST | Areal Flood Advisory | MRX | 3 hr |
| Mar 18, 3:59 AM EDT | Dense Fog Advisory | MRX | 6 hr |
| Mar 20, 4:42 PM EDT | Special Weather Statement | MRX | 48 min |
| Mar 29, 5:23 AM EDT | Severe Thunderstorm Warning | MRX | 37 min |
| Mar 29, 5:53 AM EDT | Special Weather Statement | MRX | 37 min |
| Mar 29, 6:11 AM EDT | Severe Thunderstorm Warning | MRX | 36 min |
| Apr 8, 10:52 PM EDT | Mesoscale Discussion | SPC | 113 min |
| Apr 8, 11:16 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Apr 10, 3:32 PM EDT | Frost Advisory | MRX | 18 hr |
| Apr 11, 9:32 PM EDT | Wind Advisory | MRX | 42 hr |
| Apr 11, 9:41 PM EDT | Flash Flood Watch | MRX | 32 hr |
| Apr 13, 12:43 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Apr 13, 1:14 AM EDT | Flash Flood Warning | MRX | 3 hr |
| Apr 13, 1:58 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Apr 15, 3:24 PM EDT | Frost Advisory | MRX | 18 hr |
| Apr 23, 6:40 PM EDT | Special Weather Statement | MRX | 35 min |
| Apr 25, 3:32 PM EDT | Mesoscale Discussion | SPC | 88 min |
| Apr 25, 6:11 PM EDT | Tornado Watch | SPC | 4 hr |
| Apr 29, 4:57 PM EDT | Special Weather Statement | MRX | 48 min |
| May 3, 4:08 PM EDT | Mesoscale Discussion | SPC | 67 min |
| May 8, 3:56 AM EDT | Frost Advisory | MRX | 30 hr |
| May 9, 3:26 AM EDT | Frost Advisory | MRX | 31 hr |
| May 23, 2:58 AM EDT | Dense Fog Advisory | MRX | 7 hr |
| May 28, 12:56 PM EDT | Special Weather Statement | MRX | 49 min |
| May 28, 2:04 PM EDT | Special Weather Statement | MRX | 26 min |
| May 28, 7:02 PM EDT | Special Weather Statement | MRX | 28 min |
| May 28, 7:20 PM EDT | Special Weather Statement | MRX | 25 min |
| Jun 10, 6:23 PM EDT | Mesoscale Discussion | SPC | 97 min |
| Jun 14, 12:34 PM EDT | Mesoscale Discussion | SPC | 116 min |
| Jun 14, 1:00 PM EDT | Severe Thunderstorm Warning | MRX | 34 min |
| Jun 15, 1:38 PM EDT | Special Weather Statement | MRX | 52 min |
| Jun 15, 3:08 PM EDT | Special Weather Statement | MRX | 52 min |
| Jun 21, 1:00 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 21, 3:41 PM EDT | Special Weather Statement | MRX | 34 min |
| Jun 21, 3:43 PM EDT | Severe Thunderstorm Warning | MRX | 47 min |
| Jun 22, 9:56 PM EDT | Severe Thunderstorm Warning | MRX | 49 min |
| Jun 22, 10:37 PM EDT | Special Weather Statement | MRX | 53 min |
| Jun 28, 12:49 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 28, 3:21 PM EDT | Special Weather Statement | MRX | 39 min |
| Jun 29, 5:58 PM EDT | Special Weather Statement | MRX | 47 min |
| Jun 29, 6:04 PM EDT | Severe Thunderstorm Warning | MRX | 26 min |
| Jun 29, 6:23 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Jun 29, 6:44 PM EDT | Severe Thunderstorm Warning | MRX | 46 min |
| Jun 29, 8:06 PM EDT | Flash Flood Warning | MRX | 3 hr |
| Jun 29, 10:53 PM EDT | Areal Flood Warning | MRX | 3 hr |
| Jul 1, 8:27 PM EDT | Areal Flood Advisory | MRX | 2 hr |
| Jul 1, 9:02 PM EDT | Flash Flood Warning | MRX | 84 min |
| Jul 5, 4:15 PM EDT | Severe Thunderstorm Warning | MRX | 45 min |
| Jul 9, 4:39 PM EDT | Special Weather Statement | MRX | 36 min |
| Jul 9, 5:06 PM EDT | Areal Flood Advisory | MRX | 73 min |
| Jul 17, 1:47 PM EDT | Mesoscale Discussion | SPC | 118 min |
| Jul 20, 12:57 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 20, 9:15 PM EDT | Severe Thunderstorm Warning | MRX | 45 min |
| Jul 20, 11:02 PM EDT | Special Weather Statement | MRX | 43 min |
| Jul 22, 6:47 PM EDT | Special Weather Statement | MRX | 43 min |
| Jul 22, 7:11 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Jul 23, 1:11 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 23, 2:52 PM EDT | Special Weather Statement | MRX | 23 min |
| Jul 24, 3:58 PM EDT | Special Weather Statement | MRX | 47 min |
| Jul 24, 4:15 PM EDT | Severe Thunderstorm Warning | MRX | 45 min |
| Jul 24, 4:56 PM EDT | Severe Thunderstorm Warning | MRX | 52 min |
| Jul 24, 6:09 PM EDT | Mesoscale Discussion | SPC | 66 min |
| Jul 25, 2:39 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Jul 25, 3:04 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Jul 25, 3:42 PM EDT | Flash Flood Warning | MRX | 2 hr |
| Jul 26, 5:36 PM EDT | Special Weather Statement | MRX | 24 min |
| Jul 31, 5:52 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Jul 31, 1:21 PM EDT | Mesoscale Discussion | SPC | 54 min |
| Jul 31, 5:24 PM EDT | Severe Thunderstorm Warning | MRX | 36 min |
| Aug 5, 6:40 PM EDT | Severe Thunderstorm Warning | MRX | 50 min |
| Aug 5, 7:12 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 6, 1:24 PM EDT | Special Weather Statement | MRX | 51 min |
| Aug 10, 10:40 AM EDT | Special Weather Statement | MRX | 50 min |
| Aug 15, 7:25 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 15, 9:02 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 16, 4:41 AM EDT | Dense Fog Advisory | MRX | 5 hr |
| Aug 21, 8:55 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 25, 4:52 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 26, 4:59 AM EDT | Dense Fog Advisory | MRX | 5 hr |
| Aug 30, 11:26 PM EDT | Special Weather Statement | MRX | 49 min |
| Aug 30, 11:34 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 31, 12:18 AM EDT | Areal Flood Advisory | MRX | 117 min |
| Sep 3, 1:42 PM EDT | Special Weather Statement | MRX | 48 min |
| Sep 3, 2:26 PM EDT | Special Weather Statement | MRX | 49 min |
| Sep 3, 3:05 PM EDT | Special Weather Statement | MRX | 55 min |
| Sep 3, 3:24 PM EDT | Severe Thunderstorm Warning | MRX | 34 min |
| Sep 27, 3:43 AM EDT | Dense Fog Advisory | MRX | 6 hr |
| Oct 16, 3:12 AM EDT | Frost Advisory | MRX | 31 hr |
| Oct 28, 3:52 AM EDT | Flash Flood Watch | MRX | 30 hr |
| Oct 29, 6:00 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Oct 30, 3:18 PM EDT | Freeze Watch | MRX | 37 hr |
| Nov 1, 3:16 AM EST | Freeze Warning | MRX | 30 hr |
| Nov 2, 2:39 PM EST | Freeze Warning | MRX | 18 hr |
| Nov 14, 4:04 AM EST | Wind Advisory | MRX | 39 hr |
| Dec 6, 2:33 AM EST | Freezing Fog Advisory | MRX | 7 hr |
| Dec 13, 5:28 AM EST | Dense Fog Advisory | MRX | 4 hr |
| Dec 21, 3:36 AM EST | Dense Fog Advisory | MRX | 5 hr |
| Dec 23, 2:14 PM EST | Winter Weather Advisory | MRX | 38 hr |
| Dec 23, 11:37 PM EST | Wind Advisory | MRX | 10 hr |
| Dec 29, 1:41 AM EST | Dense Fog Advisory | MRX | 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 | 19 |
| Tornado Warning | 1 |
| Severe Thunderstorm Watch | 1 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 14 |
| Special Weather Statement | 31 |
| Flooding | |
| Areal Flood Warning | 4 |
| Flash Flood Warning | 4 |
| Flash Flood Watch | 5 |
| Flood Watch | 2 |
| Areal Flood Advisory | 22 |
| Winter | |
| Winter Weather Advisory | 1 |
| Cold | |
| Freeze Warning | 2 |
| Freeze Watch | 1 |
| Frost Advisory | 5 |
| Wind and dust | |
| Wind Advisory | 4 |
| Fog and smoke | |
| Dense Fog Advisory | 8 |
| Freezing Fog Advisory | 1 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20192021
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.