Alert archive / Mississippi / Jefferson County
Weather alerts in Jefferson County, Mississippi, 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.
Jefferson County and its neighbors
Each county as a circle sized by its count in 2020. Tap one for its archive.
- Alerts
- 125
- Warnings
- 32
- Watches
- 22
- Advisories
- 24
- Busiest month
- April26 alerts
- Busiest day
- April 23, 202010 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 Jefferson County in 2020 had a tornado report inside them.
Jefferson County, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 2 | 1 | 50% | 0 | ||
| Severe thunderstorm warnings | 19 | 12 | 37% | 13 | 92% | 29 min |
| Flash flood warnings | 6 | 5 | 17% | 6 | 100% | 113 min |
Each office's whole area, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Jackson, MS: tornado warnings | 60 | 37 | 38% | 149 | 85% | 26 min |
| NWS Jackson, MS: severe thunderstorm warnings | 423 | 268 | 37% | 898 | 83% | 26 min |
| NWS Jackson, MS: flash flood warnings | 108 | 73 | 32% | 276 | 85% | 87 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, 3:07 AM CST | Flash Flood Watch | JAN | 57 hr |
| Jan 2, 2:15 PM CST | Mesoscale Discussion | SPC | 3 hr |
| Jan 2, 2:41 PM CST | Severe Thunderstorm Warning | JAN | 49 min |
| Jan 2, 4:27 PM CST | Flash Flood Warning | JAN | 3 hr |
| Jan 8, 11:38 AM CST | River Flood Advisory | JAN | 51 hr |
| Jan 9, 2:27 PM CST | Wind Advisory | JAN | 48 hr |
| Jan 10, 11:43 AM CST | River Flood Warning | JAN | 131 days |
| Jan 11, 2:22 AM CST | Mesoscale Discussion | SPC | 53 min |
| Jan 11, 2:37 AM CST | Tornado Watch | SPC | 8 hr |
| Jan 11, 4:31 AM CST | Mesoscale Discussion | SPC | 59 min |
| Jan 11, 4:44 AM CST | Severe Thunderstorm Warning | JAN | 61 min |
| Jan 11, 5:43 AM CST | Severe Thunderstorm Warning | JAN | 62 min |
| Jan 11, 6:26 AM CST | Severe Thunderstorm Warning | JAN | 64 min |
| Jan 11, 7:30 AM CST | Severe Thunderstorm Warning | JAN | 75 min |
| Jan 13, 2:36 PM CST | Dense Fog Advisory | JAN | 18 hr |
| Jan 14, 4:15 PM CST | Flash Flood Warning | JAN | 3 hr |
| Jan 28, 12:33 AM CST | Dense Fog Advisory | JAN | 10 hr |
| Feb 5, 10:28 AM CST | Mesoscale Discussion | SPC | 92 min |
| Feb 5, 11:49 AM CST | Tornado Watch | SPC | 6 hr |
| Feb 5, 1:39 PM CST | Mesoscale Discussion | SPC | 96 min |
| Feb 5, 3:41 PM CST | Mesoscale Discussion | SPC | 64 min |
| Feb 5, 3:42 PM CST | Special Weather Statement | JAN | 48 min |
| Feb 9, 4:42 AM CST | Flash Flood Watch | JAN | 47 hr |
| Feb 10, 12:39 PM CST | Mesoscale Discussion | SPC | 2 hr |
| Feb 10, 4:33 PM CST | Mesoscale Discussion | SPC | 87 min |
| Feb 10, 6:01 PM CST | Mesoscale Discussion | SPC | 89 min |
| Feb 19, 2:59 PM CST | Flash Flood Watch | JAN | 18 hr |
| Feb 25, 5:04 AM CST | Dense Fog Advisory | JAN | 4 hr |
| Mar 3, 2:38 PM CST | Flash Flood Watch | JAN | 39 hr |
| Mar 4, 1:19 AM CST | Mesoscale Discussion | SPC | 2 hr |
| Mar 4, 1:53 AM CST | Tornado Watch | SPC | 8 hr |
| Mar 4, 10:50 AM CST | Mesoscale Discussion | SPC | 115 min |
| Mar 31, 3:16 AM CDT | Mesoscale Discussion | SPC | 119 min |
| Apr 11, 3:44 PM CDT | Wind Advisory | JAN | 30 hr |
| Apr 12, 10:24 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Apr 12, 10:41 AM CDT | Tornado Watch | SPC | 10 hr |
| Apr 18, 4:31 AM CDT | Flash Flood Watch | JAN | 41 hr |
| Apr 19, 11:06 AM CDT | Mesoscale Discussion | SPC | 54 min |
| Apr 19, 11:22 AM CDT | Special Weather Statement | JAN | 38 min |
| Apr 19, 11:45 AM CDT | Tornado Watch | SPC | 9 hr |
| Apr 19, 3:07 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Apr 19, 5:40 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 19, 5:46 PM CDT | Special Weather Statement | JAN | 29 min |
| Apr 21, 2:16 PM CDT | Flash Flood Watch | JAN | 44 hr |
| Apr 22, 6:47 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Apr 22, 8:10 PM CDT | Severe Thunderstorm Warning | JAN | 65 min |
| Apr 22, 9:22 PM CDT | Special Weather Statement | JAN | 38 min |
| Apr 22, 9:30 PM CDT | Severe Thunderstorm Warning | JAN | 45 min |
| Apr 22, 9:47 PM CDT | Tornado Watch | SPC | 9 hr |
| Apr 22, 9:58 PM CDT | Severe Thunderstorm Warning | JAN | 47 min |
| Apr 22, 11:09 PM CDT | Special Weather Statement | JAN | 51 min |
| Apr 22, 11:16 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Apr 23, 2:12 AM CDT | Severe Thunderstorm Warning | JAN | 31 min |
| Apr 23, 2:21 AM CDT | Flash Flood Warning | JAN | 3 hr |
| Apr 23, 2:28 AM CDT | Mesoscale Discussion | SPC | 92 min |
| Apr 24, 11:29 PM CDT | Special Weather Statement | JAN | 46 min |
| Apr 28, 2:30 PM CDT | Severe Thunderstorm Warning | JAN | 60 min |
| Apr 29, 12:48 AM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Apr 29, 3:08 AM CDT | Special Weather Statement | JAN | 37 min |
| May 8, 8:30 AM CDT | Severe Thunderstorm Warning | JAN | 75 min |
| May 8, 11:51 AM CDT | Special Weather Statement | JAN | 54 min |
| May 15, 6:29 PM CDT | Special Weather Statement | JAN | 31 min |
| May 23, 11:56 AM CDT | Mesoscale Discussion | SPC | 94 min |
| May 23, 1:39 PM CDT | Severe Thunderstorm Warning | JAN | 51 min |
| May 23, 2:04 PM CDT | Special Weather Statement | JAN | 41 min |
| May 26, 11:56 AM CDT | River Flood Warning | JAN | 21 days |
| May 27, 12:16 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Jun 5, 2:49 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 5, 7:13 PM CDT | Severe Thunderstorm Warning | JAN | 77 min |
| Jun 6, 4:24 PM CDT | Flash Flood Watch | JAN | 57 hr |
| Jun 7, 11:26 AM CDT | Wind Advisory | JAN | 22 hr |
| Jun 8, 8:03 PM CDT | Special Weather Statement | JAN | 57 min |
| Jun 14, 3:17 PM CDT | Special Weather Statement | JAN | 28 min |
| Jun 14, 3:56 PM CDT | Special Weather Statement | JAN | 34 min |
| Jun 25, 11:57 AM CDT | Special Weather Statement | JAN | 48 min |
| Jun 25, 3:27 PM CDT | Severe Thunderstorm Warning | JAN | 78 min |
| Jul 10, 2:38 AM CDT | Heat Advisory | JAN | 16 hr |
| Jul 10, 3:19 PM CDT | Heat Advisory | JAN | 28 hr |
| Jul 11, 3:53 AM CDT | Excessive Heat Warning | JAN | 15 hr |
| Jul 11, 2:31 PM CDT | Special Weather Statement | JAN | 29 min |
| Jul 11, 2:32 PM CDT | Heat Advisory | JAN | 28 hr |
| Jul 12, 2:51 PM CDT | Heat Advisory | JAN | 28 hr |
| Jul 13, 2:58 PM CDT | Heat Advisory | JAN | 28 hr |
| Jul 14, 2:15 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Jul 14, 2:22 PM CDT | Heat Advisory | JAN | 29 hr |
| Jul 15, 7:16 PM CDT | Heat Advisory | JAN | 24 hr |
| Jul 31, 1:21 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 31, 5:21 PM CDT | Special Weather Statement | JAN | 39 min |
| Aug 14, 11:23 AM CDT | Special Weather Statement | JAN | 67 min |
| Aug 15, 3:10 AM CDT | Special Weather Statement | JAN | 50 min |
| Aug 16, 3:18 AM CDT | Heat Advisory | JAN | 15 hr |
| Aug 16, 8:30 PM CDT | Special Weather Statement | JAN | 30 min |
| Aug 27, 4:59 AM CDT | Wind Advisory | JAN | 26 hr |
| Aug 27, 6:29 AM CDT | Severe Thunderstorm Warning | JAN | 61 min |
| Aug 27, 6:36 AM CDT | Mesoscale Discussion | SPC | 114 min |
| Aug 27, 7:47 AM CDT | Tornado Watch | SPC | 8 hr |
| Aug 28, 3:16 PM CDT | Heat Advisory | JAN | 28 hr |
| Aug 31, 2:39 AM CDT | Heat Advisory | JAN | 16 hr |
| Sep 1, 2:49 AM CDT | Heat Advisory | JAN | 16 hr |
| Sep 23, 3:56 AM CDT | Flash Flood Watch | JAN | 30 hr |
| Sep 23, 1:14 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 23, 2:37 PM CDT | Tornado Watch | SPC | 7 hr |
| Sep 23, 5:20 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Sep 23, 5:23 PM CDT | Flash Flood Warning | JAN | 3 hr |
| Sep 23, 5:39 PM CDT | Severe Thunderstorm Warning | JAN | 26 min |
| Sep 23, 7:37 PM CDT | Flash Flood Warning | JAN | 3 hr |
| Sep 23, 8:10 PM CDT | Flash Flood Warning | JAN | 3 hr |
| Sep 23, 8:36 PM CDT | Tornado Warning | JAN | 28 min |
| Sep 27, 4:02 AM CDT | Dense Fog Advisory | JAN | 6 hr |
| Oct 7, 4:01 PM CDT | Flash Flood Watch | JAN | 63 hr |
| Oct 7, 10:08 PM CDT | Tropical Storm Watch | JAN | 12 hr |
| Oct 8, 9:58 AM CDT | Tropical Storm Warning | JAN | 48 hr |
| Oct 19, 7:09 PM CDT | Dense Fog Advisory | JAN | 14 hr |
| Nov 25, 6:08 AM CST | Special Weather Statement | JAN | 37 min |
| Nov 25, 6:20 AM CST | Severe Thunderstorm Warning | JAN | 40 min |
| Nov 30, 2:07 PM CST | Freeze Warning | JAN | 19 hr |
| Dec 10, 2:27 PM CST | Dense Fog Advisory | JAN | 19 hr |
| Dec 12, 8:58 PM CST | Dense Fog Advisory | JAN | 12 hr |
| Dec 13, 6:40 PM CST | Severe Thunderstorm Warning | JAN | 65 min |
| Dec 20, 7:57 PM CST | Dense Fog Advisory | JAN | 13 hr |
| Dec 23, 5:59 PM CST | Mesoscale Discussion | SPC | 3 hr |
| Dec 23, 8:40 PM CST | Tornado Watch | SPC | 5 hr |
| Dec 23, 10:37 PM CST | Severe Thunderstorm Warning | JAN | 53 min |
| Dec 23, 10:51 PM CST | Mesoscale Discussion | SPC | 114 min |
| Dec 23, 11:07 PM CST | Tornado Warning | JAN | 53 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 | 19 |
| Tornado Warning | 2 |
| Severe Thunderstorm Watch | 3 |
| Tornado Watch | 9 |
| Mesoscale Discussion | 27 |
| Special Weather Statement | 20 |
| Flooding | |
| Flash Flood Warning | 6 |
| River Flood Warning | 2 |
| Flash Flood Watch | 9 |
| River Flood Advisory | 1 |
| Heat | |
| Excessive Heat Warning | 1 |
| Heat Advisory | 11 |
| Cold | |
| Freeze Warning | 1 |
| Wind and dust | |
| Wind Advisory | 4 |
| Fog and smoke | |
| Dense Fog Advisory | 8 |
| Tropical | |
| Tropical Storm Warning | 1 |
| Tropical Storm Watch | 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.