Alert archive / Tennessee / Hamilton County
Weather alerts in Hamilton County, Tennessee, 2020
125 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Hamilton County and its neighbors
Each county as a circle sized by its count in 2020. Tap one for its archive.
- Alerts
- 125
- Warnings
- 44
- Watches
- 14
- Advisories
- 25
- Busiest month
- February27 alerts
- Busiest day
- April 13, 20208 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 2 tornado warnings covering Hamilton County in 2020 had a tornado report inside them; 1 of 2 tornado reports fell inside a warning, on average 4 minutes after it went out.
Hamilton County, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 2 | 1 | 50% | 2 | 50% | 4 min |
| Severe thunderstorm warnings | 13 | 12 | 8% | 10 | 70% | 33 min |
| Flash flood warnings | 3 | 3 | 0% | 1 | 100% | 153 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 1, 10:44 AM EST | River Flood Warning | FFC | 3 days |
| Jan 2, 10:39 PM EST | Areal Flood Advisory | MRX | 6 hr |
| Jan 3, 11:27 AM EST | River Flood Warning | MRX | 41 hr |
| Jan 10, 2:39 PM EST | Wind Advisory | MRX | 34 hr |
| Jan 11, 10:28 AM EST | Mesoscale Discussion | SPC | 92 min |
| Jan 11, 1:20 PM EST | Mesoscale Discussion | SPC | 85 min |
| Jan 11, 1:42 PM EST | Tornado Watch | SPC | 7 hr |
| Jan 11, 2:56 PM EST | Severe Thunderstorm Warning | MRX | 64 min |
| Jan 11, 3:39 PM EST | Tornado Warning | MRX | 20 min |
| Jan 11, 3:49 PM EST | Severe Thunderstorm Warning | MRX | 56 min |
| Jan 14, 11:30 AM EST | River Flood Warning | FFC | 3 hr |
| Jan 16, 9:55 AM EST | River Flood Warning | FFC | 15 hr |
| Feb 4, 3:46 PM EST | Flash Flood Watch | MRX | 47 hr |
| Feb 5, 12:19 PM EST | Special Weather Statement | MRX | 41 min |
| Feb 5, 1:47 PM EST | Flash Flood Warning | MRX | 3 hr |
| Feb 5, 2:05 PM EST | Areal Flood Advisory | MRX | 3 hr |
| Feb 5, 4:54 PM EST | River Flood Warning | FFC | 61 hr |
| Feb 5, 7:33 PM EST | Mesoscale Discussion | SPC | 117 min |
| Feb 5, 9:14 PM EST | River Flood Warning | MRX | 71 hr |
| Feb 5, 9:44 PM EST | Areal Flood Advisory | MRX | 6 hr |
| Feb 6, 3:02 AM EST | Areal Flood Warning | MRX | 6 hr |
| Feb 6, 8:56 AM EST | Areal Flood Warning | MRX | 12 hr |
| Feb 6, 9:23 AM EST | River Flood Warning | FFC | 55 hr |
| Feb 6, 8:24 PM EST | Areal Flood Warning | MRX | 24 hr |
| Feb 7, 1:15 AM EST | River Flood Warning | MRX | 9 hr |
| Feb 7, 2:57 PM EST | Winter Weather Advisory | MRX | 25 hr |
| Feb 7, 8:26 PM EST | Areal Flood Warning | MRX | 12 hr |
| Feb 9, 1:24 AM EST | Freezing Fog Advisory | MRX | 8 hr |
| Feb 9, 3:35 AM EST | Flood Watch | MRX | 36 hr |
| Feb 9, 11:50 AM EST | River Flood Warning | FFC | 5 days |
| Feb 10, 10:35 AM EST | River Flood Warning | MRX | 4 days |
| Feb 10, 10:51 AM EST | River Flood Warning | FFC | 67 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, 8:12 PM EST | Severe Thunderstorm Warning | MRX | 48 min |
| Feb 12, 8:30 PM EST | Severe Thunderstorm Warning | MRX | 45 min |
| Feb 12, 8:37 PM EST | Mesoscale Discussion | SPC | 83 min |
| Feb 12, 8:56 PM EST | Severe Thunderstorm Warning | MRX | 64 min |
| Feb 18, 3:02 PM EST | River Flood Warning | FFC | 13 hr |
| Mar 3, 6:15 AM EST | Special Weather Statement | MRX | 45 min |
| Mar 3, 8:06 AM EST | Special Weather Statement | MRX | 39 min |
| Mar 17, 12:45 PM EDT | River Flood Warning | FFC | 6 hr |
| Mar 18, 3:59 AM EDT | Dense Fog Advisory | MRX | 6 hr |
| Mar 23, 8:59 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Mar 23, 11:15 AM EDT | River Flood Warning | FFC | 67 hr |
| Mar 24, 4:31 AM EDT | Flash Flood Watch | MRX | 23 hr |
| Mar 24, 10:32 AM EDT | River Flood Warning | MRX | 53 hr |
| Mar 24, 3:47 PM EDT | River Flood Warning | FFC | 55 hr |
| Mar 24, 8:05 PM EDT | Mesoscale Discussion | SPC | 55 min |
| Mar 24, 8:44 PM EDT | Tornado Watch | SPC | 3 hr |
| Mar 24, 9:34 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Mar 24, 9:55 PM EDT | Special Weather Statement | MRX | 50 min |
| Mar 29, 2:50 AM EDT | Mesoscale Discussion | SPC | 85 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 9, 1:13 AM EDT | Special Weather Statement | MRX | 47 min |
| 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 12, 10:26 AM EDT | River Flood Warning | MRX | 3 days |
| Apr 12, 10:30 AM EDT | River Flood Warning | FFC | 48 hr |
| Apr 12, 6:48 PM EDT | River Flood Warning | FFC | 63 hr |
| Apr 12, 10:08 PM EDT | Special Weather Statement | MRX | 52 min |
| Apr 12, 11:03 PM EDT | Severe Thunderstorm Warning | MRX | 57 min |
| Apr 12, 11:16 PM EDT | Tornado Warning | MRX | 29 min |
| Apr 12, 11:41 PM EDT | Severe Thunderstorm Warning | MRX | 49 min |
| Apr 12, 11:59 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Apr 13, 12:19 AM EDT | Areal Flood Warning | MRX | 3 hr |
| Apr 13, 12:59 AM EDT | Flash Flood Warning | MRX | 3 hr |
| Apr 13, 1:46 AM EDT | Flash Flood Warning | MRX | 3 hr |
| Apr 25, 3:32 PM EDT | Mesoscale Discussion | SPC | 88 min |
| Apr 25, 4:03 PM EDT | Special Weather Statement | MRX | 42 min |
| Apr 29, 3:18 PM EDT | Special Weather Statement | MRX | 42 min |
| Apr 29, 3:55 PM EDT | Special Weather Statement | MRX | 50 min |
| May 3, 4:08 PM EDT | Mesoscale Discussion | SPC | 67 min |
| May 3, 4:40 PM EDT | Severe Thunderstorm Watch | SPC | 4 hr |
| May 3, 7:02 PM EDT | Severe Thunderstorm Warning | MRX | 43 min |
| May 3, 7:18 PM EDT | Mesoscale Discussion | SPC | 57 min |
| May 4, 7:21 PM EDT | Mesoscale Discussion | SPC | 54 min |
| May 4, 7:42 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 4, 9:16 PM EDT | Mesoscale Discussion | SPC | 89 min |
| May 4, 11:40 PM EDT | Special Weather Statement | MRX | 50 min |
| May 5, 12:08 AM EDT | Mesoscale Discussion | SPC | 97 min |
| May 9, 3:26 AM EDT | Frost Advisory | MRX | 31 hr |
| May 18, 6:36 PM EDT | Special Weather Statement | MRX | 54 min |
| May 22, 11:14 PM EDT | Special Weather Statement | MRX | 46 min |
| May 22, 11:57 PM EDT | Special Weather Statement | MRX | 48 min |
| Jun 10, 6:23 PM EDT | Mesoscale Discussion | SPC | 97 min |
| Jun 14, 2:41 PM EDT | Special Weather Statement | MRX | 64 min |
| Jun 21, 3:27 PM EDT | Special Weather Statement | MRX | 33 min |
| Jun 21, 4:13 PM EDT | Special Weather Statement | MRX | 47 min |
| Jun 22, 7:57 PM EDT | Special Weather Statement | MRX | 63 min |
| Jun 22, 8:38 PM EDT | Severe Thunderstorm Warning | MRX | 67 min |
| Jun 28, 8:17 PM EDT | Severe Thunderstorm Warning | MRX | 28 min |
| Jun 29, 4:44 PM EDT | Special Weather Statement | MRX | 46 min |
| Jul 5, 5:51 PM EDT | Severe Thunderstorm Warning | MRX | 24 min |
| Jul 5, 6:44 PM EDT | Special Weather Statement | MRX | 46 min |
| Jul 5, 7:08 PM EDT | Special Weather Statement | MRX | 52 min |
| Jul 19, 3:30 AM EDT | Heat Advisory | MRX | 15 hr |
| Jul 20, 12:57 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 23, 12:37 PM EDT | Severe Thunderstorm Warning | MRX | 38 min |
| Jul 23, 1:14 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Jul 31, 1:21 PM EDT | Mesoscale Discussion | SPC | 54 min |
| Aug 6, 2:00 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 10, 2:17 PM EDT | Mesoscale Discussion | SPC | 118 min |
| Aug 10, 6:38 PM EDT | Severe Thunderstorm Warning | MRX | 45 min |
| Aug 10, 7:17 PM EDT | Special Weather Statement | MRX | 43 min |
| Aug 12, 4:58 PM EDT | Special Weather Statement | MRX | 32 min |
| Aug 12, 5:38 PM EDT | Areal Flood Advisory | MRX | 112 min |
| Aug 13, 4:43 PM EDT | Special Weather Statement | MRX | 47 min |
| Aug 21, 5:18 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Aug 28, 6:19 PM EDT | Mesoscale Discussion | SPC | 116 min |
| Sep 23, 3:57 PM EDT | Flood Watch | MRX | 33 hr |
| Oct 28, 3:52 AM EDT | Flash Flood Watch | MRX | 30 hr |
| Oct 28, 10:47 AM EDT | Wind Advisory | MRX | 28 hr |
| Oct 28, 11:17 AM EDT | River Flood Warning | MRX | 23 hr |
| Oct 29, 4:11 AM EDT | Areal Flood Advisory | MRX | 3 hr |
| Nov 1, 3:16 AM EST | Freeze Warning | MRX | 30 hr |
| Nov 2, 2:39 PM EST | Frost Advisory | MRX | 18 hr |
| Nov 15, 10:07 AM EST | Special Weather Statement | MRX | 38 min |
| 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, 11:37 PM EST | Wind Advisory | MRX | 10 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 | 13 |
| Tornado Warning | 2 |
| Severe Thunderstorm Watch | 3 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 18 |
| Special Weather Statement | 24 |
| Flooding | |
| Areal Flood Warning | 5 |
| Flash Flood Warning | 3 |
| River Flood Warning | 20 |
| Flash Flood Watch | 6 |
| Flood Watch | 3 |
| Areal Flood Advisory | 11 |
| Winter | |
| Winter Weather Advisory | 1 |
| Heat | |
| Heat Advisory | 1 |
| Cold | |
| Freeze Warning | 1 |
| Frost Advisory | 3 |
| Wind and dust | |
| Wind Advisory | 4 |
| Fog and smoke | |
| Dense Fog Advisory | 3 |
| Freezing Fog Advisory | 2 |
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.