Alert archive / Tennessee / Jefferson County
Weather alerts in Jefferson County, Tennessee, 2018
94 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Jefferson County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 94
- Warnings
- 30
- Watches
- 11
- Advisories
- 17
- Busiest month
- June17 alerts
- Busiest day
- April 4, 20187 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Jefferson County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 16 | 13 | 19% | 8 | 88% | 24 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Morristown, TN: tornado warnings | 8 | 0 | 100% | 0 | ||
| NWS Morristown, TN: severe thunderstorm warnings | 210 | 162 | 23% | 267 | 84% | 22 min |
| NWS Morristown, TN: flash flood warnings | 37 | 27 | 27% | 35 | 83% | 73 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 7, 4:06 AM EST | Winter Weather Advisory | MRX | 37 hr |
| Jan 15, 10:08 AM EST | Winter Weather Advisory | MRX | 45 hr |
| Feb 1, 3:12 AM EST | Winter Weather Advisory | MRX | 30 hr |
| Feb 9, 3:46 AM EST | Flood Watch | MRX | 63 hr |
| Feb 10, 10:20 PM EST | Areal Flood Advisory | MRX | 4 hr |
| Feb 11, 5:26 AM EST | Areal Flood Advisory | MRX | 3 hr |
| Feb 11, 8:30 AM EST | Areal Flood Advisory | MRX | 4 hr |
| Feb 27, 4:03 AM EST | Flood Watch | MRX | 63 hr |
| Mar 17, 3:25 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Mar 17, 4:33 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Mar 17, 7:06 PM EDT | Mesoscale Discussion | SPC | 114 min |
| Mar 19, 9:59 PM EDT | Special Weather Statement | MRX | 61 min |
| Mar 21, 3:40 AM EDT | Freeze Warning | MRX | 30 hr |
| Mar 22, 3:36 AM EDT | Freeze Warning | MRX | 30 hr |
| Mar 24, 9:55 PM EDT | Special Weather Statement | MRX | 50 min |
| Apr 3, 9:16 PM EDT | Mesoscale Discussion | SPC | 89 min |
| Apr 3, 9:50 PM EDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Apr 3, 11:49 PM EDT | Mesoscale Discussion | SPC | 86 min |
| Apr 4, 1:26 AM EDT | Severe Thunderstorm Warning | MRX | 64 min |
| Apr 4, 1:44 AM EDT | Severe Thunderstorm Warning | MRX | 46 min |
| Apr 4, 2:00 AM EDT | Mesoscale Discussion | SPC | 105 min |
| Apr 4, 4:32 AM EDT | Freeze Warning | MRX | 28 hr |
| Apr 6, 3:26 PM EDT | Freeze Watch | MRX | 12 hr |
| Apr 7, 3:28 AM EDT | Freeze Warning | MRX | 31 hr |
| Apr 10, 3:25 PM EDT | Frost Advisory | MRX | 18 hr |
| Apr 16, 4:28 AM EDT | Freeze Watch | MRX | 11 hr |
| Apr 16, 4:28 AM EDT | Freeze Warning | MRX | 29 hr |
| Apr 19, 3:05 AM EDT | Frost Advisory | MRX | 30 hr |
| Apr 22, 9:40 AM EDT | Wind Advisory | MRX | 40 hr |
| May 5, 3:27 PM EDT | Mesoscale Discussion | SPC | 93 min |
| May 15, 5:16 PM EDT | Special Weather Statement | MRX | 44 min |
| May 15, 6:13 PM EDT | Severe Thunderstorm Warning | MRX | 47 min |
| May 15, 6:20 PM EDT | Severe Thunderstorm Warning | MRX | 40 min |
| May 18, 3:12 PM EDT | Special Weather Statement | MRX | 48 min |
| May 26, 3:17 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| May 26, 5:07 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| May 28, 4:20 AM EDT | Flash Flood Watch | MRX | 64 hr |
| May 30, 7:23 AM EDT | River Flood Warning | MRX | 24 hr |
| May 31, 4:27 PM EDT | Mesoscale Discussion | SPC | 93 min |
| May 31, 6:47 PM EDT | Severe Thunderstorm Warning | MRX | 43 min |
| May 31, 7:03 PM EDT | Severe Thunderstorm Warning | MRX | 31 min |
| May 31, 7:27 PM EDT | Severe Thunderstorm Warning | MRX | 48 min |
| Jun 3, 3:24 PM EDT | Mesoscale Discussion | SPC | 66 min |
| Jun 3, 3:33 PM EDT | Special Weather Statement | MRX | 42 min |
| Jun 24, 3:47 PM EDT | Special Weather Statement | MRX | 43 min |
| Jun 24, 4:08 PM EDT | Special Weather Statement | MRX | 67 min |
| Jun 24, 4:13 PM EDT | Severe Thunderstorm Warning | MRX | 47 min |
| Jun 24, 4:36 PM EDT | Areal Flood Warning | MRX | 3 hr |
| Jun 24, 6:33 PM EDT | Special Weather Statement | MRX | 42 min |
| Jun 25, 3:35 AM EDT | Special Weather Statement | MRX | 25 min |
| Jun 25, 4:00 AM EDT | Special Weather Statement | MRX | 30 min |
| Jun 25, 12:29 PM EDT | Mesoscale Discussion | SPC | 61 min |
| Jun 25, 1:02 PM EDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 25, 1:45 PM EDT | Severe Thunderstorm Warning | MRX | 60 min |
| Jun 26, 2:43 PM EDT | Mesoscale Discussion | SPC | 62 min |
| Jun 26, 4:49 PM EDT | Severe Thunderstorm Warning | MRX | 41 min |
| Jun 26, 5:27 PM EDT | Severe Thunderstorm Warning | MRX | 78 min |
| Jun 27, 2:29 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Jun 28, 5:43 AM EDT | Special Weather Statement | MRX | 47 min |
| Jul 6, 5:41 PM EDT | Special Weather Statement | MRX | 49 min |
| Jul 16, 4:14 PM EDT | Special Weather Statement | MRX | 46 min |
| Jul 20, 8:02 PM EDT | Tornado Watch | SPC | 7 hr |
| Jul 20, 10:10 PM EDT | Severe Thunderstorm Warning | MRX | 65 min |
| Jul 20, 10:52 PM EDT | Mesoscale Discussion | SPC | 53 min |
| Jul 21, 3:10 AM EDT | Special Weather Statement | MRX | 50 min |
| Jul 21, 3:37 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 8, 3:10 PM EDT | Severe Thunderstorm Warning | MRX | 50 min |
| Aug 31, 2:33 PM EDT | Special Weather Statement | MRX | 27 min |
| Aug 31, 2:58 PM EDT | Special Weather Statement | MRX | 47 min |
| Sep 1, 6:22 PM EDT | Special Weather Statement | MRX | 38 min |
| Sep 2, 5:00 PM EDT | Severe Thunderstorm Warning | MRX | 45 min |
| Sep 5, 5:12 PM EDT | Special Weather Statement | MRX | 48 min |
| Sep 9, 5:20 PM EDT | Special Weather Statement | MRX | 40 min |
| Sep 9, 6:33 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 15, 10:17 AM EDT | River Flood Warning | MRX | 71 hr |
| Sep 26, 4:23 AM EDT | Flash Flood Watch | MRX | 40 hr |
| Sep 27, 7:24 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Oct 11, 7:22 AM EDT | Areal Flood Advisory | MRX | 5 hr |
| Oct 11, 10:38 AM EDT | River Flood Warning | MRX | 42 hr |
| Oct 21, 3:35 AM EDT | Freeze Warning | MRX | 29 hr |
| Oct 28, 3:49 AM EDT | Wind Advisory | MRX | 24 hr |
| Nov 6, 2:40 AM EST | Mesoscale Discussion | SPC | 65 min |
| Nov 6, 4:52 AM EST | Severe Thunderstorm Warning | MRX | 38 min |
| Nov 6, 5:21 AM EST | Severe Thunderstorm Warning | MRX | 39 min |
| Nov 8, 11:04 AM EST | Freeze Warning | MRX | 47 hr |
| Nov 10, 12:35 PM EST | Freeze Warning | MRX | 21 hr |
| Nov 15, 4:43 PM EST | River Flood Statement | MRX | 14 hr |
| Dec 2, 3:10 AM EST | Special Weather Statement | MRX | 50 min |
| Dec 8, 3:10 PM EST | Winter Weather Advisory | MRX | 43 hr |
| Dec 11, 4:44 AM EST | Freezing Fog Advisory | MRX | 6 hr |
| Dec 21, 7:47 PM EST | River Flood Warning | MRX | 13 hr |
| Dec 26, 12:09 PM EST | River Flood Warning | MRX | 4 days |
| Dec 26, 3:42 PM EST | Flash Flood Watch | MRX | 48 hr |
| Dec 28, 9:57 PM EST | Dense Fog 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 | 16 |
| Severe Thunderstorm Watch | 3 |
| Tornado Watch | 1 |
| Mesoscale Discussion | 15 |
| Special Weather Statement | 20 |
| Flooding | |
| Areal Flood Warning | 1 |
| River Flood Warning | 5 |
| Flash Flood Watch | 3 |
| Flood Watch | 2 |
| Areal Flood Advisory | 7 |
| River Flood Statement | 1 |
| Winter | |
| Winter Weather Advisory | 4 |
| Cold | |
| Freeze Warning | 8 |
| Freeze Watch | 2 |
| Frost Advisory | 2 |
| Wind and dust | |
| Wind Advisory | 2 |
| Fog and smoke | |
| Dense Fog Advisory | 1 |
| Freezing Fog Advisory | 1 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20172019
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.