Alert archive / Tennessee / Jefferson County
Weather alerts in Jefferson County, Tennessee, 2017
97 weather alerts in 2017, 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 2017. Tap one for its archive.
- Alerts
- 97
- Warnings
- 25
- Watches
- 7
- Advisories
- 26
- Busiest month
- March20 alerts
- Busiest day
- March 1, 20179 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, 2017
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 12 | 10 | 17% | 3 | 100% | 16 min |
| Flash flood warnings | 2 | 1 | 50% | 0 |
Each office's whole area, 2017
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Morristown, TN: tornado warnings | 2 | 0 | 100% | 0 | ||
| NWS Morristown, TN: severe thunderstorm warnings | 110 | 88 | 20% | 209 | 78% | 24 min |
| NWS Morristown, TN: flash flood warnings | 8 | 6 | 25% | 17 | 65% | 48 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 4, 3:11 PM EST | Winter Weather Advisory | MRX | 31 hr |
| Jan 5, 3:24 PM EST | Winter Storm Watch | MRX | 13 hr |
| Jan 5, 3:24 PM EST | Winter Storm Warning | MRX | 43 hr |
| Jan 5, 3:24 PM EST | Winter Weather Advisory | MRX | 43 hr |
| Jan 6, 8:56 PM EST | Mesoscale Discussion | SPC | 6 hr |
| Jan 7, 3:34 AM EST | Winter Weather Advisory | MRX | 6 hr |
| Jan 14, 3:00 AM EST | Dense Fog Advisory | MRX | 7 hr |
| Jan 16, 4:06 AM EST | Dense Fog Advisory | MRX | 6 hr |
| Feb 1, 6:40 PM EST | Special Weather Statement | MRX | 65 min |
| Feb 7, 3:32 PM EST | Special Weather Statement | MRX | 43 min |
| Feb 8, 8:04 PM EST | Mesoscale Discussion | SPC | 86 min |
| Feb 8, 9:33 PM EST | Special Weather Statement | MRX | 42 min |
| Feb 8, 9:55 PM EST | Mesoscale Discussion | SPC | 65 min |
| Feb 23, 1:09 AM EST | Dense Fog Advisory | MRX | 9 hr |
| Feb 25, 3:15 AM EST | Special Weather Statement | MRX | 45 min |
| Feb 25, 3:25 AM EST | Severe Thunderstorm Warning | MRX | 35 min |
| Feb 25, 3:57 AM EST | Severe Thunderstorm Warning | MRX | 48 min |
| Feb 28, 3:25 AM EST | Wind Advisory | MRX | 44 hr |
| Mar 1, 7:47 AM EST | Severe Thunderstorm Watch | SPC | 5 hr |
| Mar 1, 11:15 AM EST | Special Weather Statement | MRX | 60 min |
| Mar 1, 1:04 PM EST | Special Weather Statement | MRX | 56 min |
| Mar 1, 2:07 PM EST | Special Weather Statement | MRX | 53 min |
| Mar 1, 2:22 PM EST | Areal Flood Advisory | MRX | 3 hr |
| Mar 1, 3:00 PM EST | Flash Flood Warning | MRX | 3 hr |
| Mar 1, 3:03 PM EST | Special Weather Statement | MRX | 57 min |
| Mar 1, 4:31 PM EST | Areal Flood Advisory | MRX | 3 hr |
| Mar 1, 4:46 PM EST | Flash Flood Warning | MRX | 3 hr |
| Mar 10, 2:24 AM EST | Special Weather Statement | MRX | 51 min |
| Mar 10, 4:03 AM EST | Freeze Warning | MRX | 29 hr |
| Mar 10, 3:14 PM EST | Freeze Watch | MRX | 232 days |
| Mar 11, 3:39 AM EST | Freeze Warning | MRX | 27 hr |
| Mar 12, 3:37 AM EDT | Freeze Warning | MRX | 28 hr |
| Mar 13, 3:22 PM EDT | Freeze Warning | MRX | 46 hr |
| Mar 15, 3:44 AM EDT | Freeze Warning | MRX | 31 hr |
| Mar 15, 3:27 PM EDT | Freeze Watch | MRX | 23 hr |
| Mar 16, 2:47 PM EDT | Freeze Warning | MRX | 19 hr |
| Mar 21, 8:54 PM EDT | Special Weather Statement | MRX | 66 min |
| Mar 27, 9:28 PM EDT | Severe Thunderstorm Warning | MRX | 23 min |
| Apr 5, 7:57 PM EDT | Mesoscale Discussion | SPC | 48 min |
| Apr 5, 8:10 PM EDT | Wind Advisory | MRX | 31 hr |
| Apr 5, 9:19 PM EDT | Severe Thunderstorm Warning | MRX | 26 min |
| Apr 5, 9:42 PM EDT | Severe Thunderstorm Warning | MRX | 39 min |
| Apr 5, 10:15 PM EDT | Severe Thunderstorm Warning | MRX | 27 min |
| Apr 7, 3:06 PM EDT | Frost Advisory | MRX | 18 hr |
| Apr 21, 2:13 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 22, 4:11 AM EDT | Flash Flood Watch | MRX | 47 hr |
| Apr 22, 5:28 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Apr 22, 5:33 PM EDT | Severe Thunderstorm Warning | MRX | 57 min |
| Apr 22, 10:39 PM EDT | Areal Flood Advisory | MRX | 3 hr |
| Apr 23, 9:04 AM EDT | Areal Flood Advisory | MRX | 6 hr |
| Apr 23, 12:44 PM EDT | Areal Flood Warning | MRX | 6 hr |
| Apr 23, 6:31 PM EDT | Areal Flood Warning | MRX | 15 hr |
| Apr 29, 4:34 PM EDT | Severe Thunderstorm Warning | MRX | 24 min |
| Apr 30, 2:47 PM EDT | Wind Advisory | MRX | 29 hr |
| May 3, 3:47 AM EDT | Wind Advisory | MRX | 42 hr |
| May 4, 10:42 PM EDT | Special Weather Statement | MRX | 48 min |
| May 4, 11:02 PM EDT | Severe Thunderstorm Warning | MRX | 43 min |
| May 24, 7:41 AM EDT | Mesoscale Discussion | SPC | 3 hr |
| May 24, 12:06 PM EDT | Severe Thunderstorm Warning | MRX | 43 min |
| May 24, 1:19 PM EDT | Tornado Watch | SPC | 7 hr |
| May 24, 3:50 PM EDT | Mesoscale Discussion | SPC | 55 min |
| May 27, 6:11 PM EDT | Mesoscale Discussion | SPC | 64 min |
| May 27, 6:55 PM EDT | Severe Thunderstorm Watch | SPC | 9 hr |
| May 27, 10:31 PM EDT | Severe Thunderstorm Warning | MRX | 59 min |
| May 27, 10:46 PM EDT | Mesoscale Discussion | SPC | 89 min |
| Jun 4, 2:11 PM EDT | Special Weather Statement | MRX | 49 min |
| Jun 4, 4:17 PM EDT | Special Weather Statement | MRX | 43 min |
| Jun 13, 6:15 PM EDT | Special Weather Statement | MRX | 45 min |
| Jun 13, 8:48 PM EDT | Special Weather Statement | MRX | 42 min |
| Jun 14, 1:17 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 14, 1:55 PM EDT | Special Weather Statement | MRX | 50 min |
| Jun 15, 4:26 PM EDT | Special Weather Statement | MRX | 49 min |
| Jul 1, 1:18 PM EDT | Mesoscale Discussion | SPC | 117 min |
| Jul 1, 4:35 PM EDT | Areal Flood Advisory | MRX | 115 min |
| Jul 3, 4:40 PM EDT | Special Weather Statement | MRX | 50 min |
| Jul 5, 3:21 PM EDT | Special Weather Statement | MRX | 24 min |
| Jul 5, 4:01 PM EDT | Special Weather Statement | MRX | 44 min |
| Jul 6, 1:15 PM EDT | Mesoscale Discussion | SPC | 60 min |
| Jul 6, 9:32 PM EDT | Special Weather Statement | MRX | 43 min |
| Jul 8, 2:23 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 9, 5:27 AM EDT | Dense Fog Advisory | MRX | 5 hr |
| Jul 23, 10:09 PM EDT | Special Weather Statement | MRX | 51 min |
| Jul 23, 10:16 PM EDT | Severe Thunderstorm Warning | MRX | 44 min |
| Jul 23, 10:44 PM EDT | Special Weather Statement | MRX | 31 min |
| Aug 11, 7:11 PM EDT | Areal Flood Advisory | MRX | 4 hr |
| Sep 10, 6:11 AM EDT | Wind Advisory | MRX | 52 hr |
| Oct 7, 3:34 PM EDT | Wind Advisory | MRX | 36 hr |
| Oct 8, 9:59 AM EDT | River Flood Warning | MRX | 60 hr |
| Oct 24, 3:03 PM EDT | Frost Advisory | MRX | 18 hr |
| Oct 29, 3:58 AM EDT | Freeze Warning | MRX | 30 hr |
| Nov 17, 2:49 PM EST | Wind Advisory | MRX | 37 hr |
| Nov 18, 9:09 PM EST | Special Weather Statement | MRX | 51 min |
| Dec 3, 5:54 AM EST | Dense Fog Advisory | MRX | 3 hr |
| Dec 18, 10:13 PM EST | Dense Fog Advisory | MRX | 12 hr |
| Dec 22, 3:17 PM EST | Wind Advisory | MRX | 24 hr |
| Dec 23, 11:05 AM EST | Special Weather Statement | MRX | 40 min |
| Dec 23, 11:29 AM EST | Special Weather Statement | MRX | 61 min |
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 | 12 |
| Severe Thunderstorm Watch | 2 |
| Tornado Watch | 1 |
| Mesoscale Discussion | 13 |
| Special Weather Statement | 26 |
| Flooding | |
| Areal Flood Warning | 2 |
| Flash Flood Warning | 2 |
| River Flood Warning | 1 |
| Flash Flood Watch | 1 |
| Areal Flood Advisory | 7 |
| Winter | |
| Winter Storm Warning | 1 |
| Winter Storm Watch | 1 |
| Winter Weather Advisory | 3 |
| Cold | |
| Freeze Warning | 7 |
| Freeze Watch | 2 |
| Frost Advisory | 2 |
| Wind and dust | |
| Wind Advisory | 8 |
| Fog and smoke | |
| Dense Fog Advisory | 6 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20162018
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.