Alert archive / Mississippi / Jefferson County
Weather alerts in Jefferson County, Mississippi, 2009
160 weather alerts in 2009, 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 2009. Tap one for its archive.
- Alerts
- 160
- Warnings
- 33
- Watches
- 35
- Advisories
- 47
- Busiest month
- March30 alerts
- Busiest day
- March 27, 20098 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
2 of 4 tornado warnings covering Jefferson County in 2009 had a tornado report inside them.
Jefferson County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 4 | 2 | 50% | 0 | ||
| Severe thunderstorm warnings | 20 | 11 | 45% | 5 | 80% | 32 min |
| Flash flood warnings | 5 | 2 | 60% | 0 |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Jackson, MS: tornado warnings | 126 | 21 | 83% | 41 | 73% | 18 min |
| NWS Jackson, MS: severe thunderstorm warnings | 600 | 264 | 56% | 647 | 83% | 26 min |
| NWS Jackson, MS: flash flood warnings | 191 | 100 | 48% | 198 | 93% | 107 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 3, 12:32 PM CST | Mesoscale Discussion | SPC | 88 min |
| Jan 3, 4:27 PM CST | Mesoscale Discussion | SPC | 33 min |
| Jan 3, 4:29 PM CST | Severe Thunderstorm Watch | SPC | 3 hr |
| Jan 3, 6:29 PM CST | Mesoscale Discussion | SPC | 61 min |
| Jan 5, 4:14 AM CST | Flash Flood Watch | JAN | 38 hr |
| Jan 6, 7:09 AM CST | Dense Fog Advisory | JAN | 102 min |
| Jan 14, 2:36 PM CST | Hard Freeze Watch | JAN | 19 hr |
| Jan 15, 4:35 AM CST | Hard Freeze Warning | JAN | 47 hr |
| Jan 15, 9:56 AM CST | Lake Wind Advisory | JAN | 8 hr |
| Jan 23, 11:47 AM CST | Lake Wind Advisory | JAN | 4 hr |
| Feb 1, 2:38 PM CST | Lake Wind Advisory | JAN | 25 hr |
| Feb 8, 3:34 PM CST | Lake Wind Advisory | JAN | 32 hr |
| Feb 10, 5:26 AM CST | Wind Advisory | JAN | 33 hr |
| Feb 11, 4:01 AM CST | Mesoscale Discussion | SPC | 89 min |
| Feb 17, 4:15 AM CST | Lake Wind Advisory | JAN | 24 hr |
| Feb 18, 1:22 PM CST | Mesoscale Discussion | SPC | 53 min |
| Feb 19, 6:30 AM CST | Lake Wind Advisory | JAN | 9 hr |
| Feb 25, 7:40 PM CST | Lake Wind Advisory | JAN | 26 hr |
| Feb 28, 3:52 PM CST | Lake Wind Advisory | JAN | 26 hr |
| Mar 19, 4:44 AM CDT | Dense Fog Advisory | JAN | 5 hr |
| Mar 23, 3:49 AM CDT | Lake Wind Advisory | JAN | 12 hr |
| Mar 23, 3:38 PM CDT | Lake Wind Advisory | JAN | 27 hr |
| Mar 25, 2:20 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Mar 25, 3:38 AM CDT | Flood Watch | JAN | 11 hr |
| Mar 25, 3:02 PM CDT | Flash Flood Watch | JAN | 13 hr |
| Mar 25, 8:32 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Mar 25, 8:54 PM CDT | Tornado Watch | SPC | 7 hr |
| Mar 25, 10:58 PM CDT | Severe Thunderstorm Warning | JAN | 47 min |
| Mar 25, 11:44 PM CDT | Severe Thunderstorm Warning | JAN | 61 min |
| Mar 26, 4:07 AM CDT | Flash Flood Watch | JAN | 24 hr |
| Mar 26, 5:36 PM CDT | Mesoscale Discussion | SPC | 54 min |
| Mar 26, 5:56 PM CDT | Tornado Watch | SPC | 7 hr |
| Mar 26, 8:09 PM CDT | Severe Thunderstorm Warning | JAN | 25 min |
| Mar 26, 8:54 PM CDT | Flash Flood Warning | JAN | 3 hr |
| Mar 27, 3:53 AM CDT | Flash Flood Watch | JAN | 26 hr |
| Mar 27, 4:16 PM CDT | Tornado Watch | SPC | 4 hr |
| Mar 27, 6:08 PM CDT | Severe Thunderstorm Warning | JAN | 67 min |
| Mar 27, 6:18 PM CDT | Mesoscale Discussion | SPC | 57 min |
| Mar 27, 6:23 PM CDT | Tornado Warning | JAN | 52 min |
| Mar 27, 6:45 PM CDT | Tornado Warning | JAN | 60 min |
| Mar 27, 7:51 PM CDT | Tornado Watch | SPC | 9 hr |
| Mar 27, 11:06 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Mar 28, 3:54 AM CDT | Lake Wind Advisory | JAN | 15 hr |
| Mar 31, 8:58 AM CDT | Mesoscale Discussion | SPC | 92 min |
| Mar 31, 9:37 AM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Mar 31, 11:32 AM CDT | Severe Thunderstorm Warning | JAN | 43 min |
| Mar 31, 11:54 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Mar 31, 12:12 PM CDT | Severe Thunderstorm Warning | JAN | 41 min |
| Mar 31, 2:44 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Apr 2, 8:01 AM CDT | Mesoscale Discussion | SPC | 59 min |
| Apr 2, 9:24 AM CDT | Tornado Watch | SPC | 7 hr |
| Apr 5, 12:43 PM CDT | Lake Wind Advisory | JAN | 27 hr |
| Apr 5, 9:42 PM CDT | Freeze Watch | JAN | 17 hr |
| Apr 6, 2:54 PM CDT | Freeze Warning | JAN | 17 hr |
| Apr 8, 2:35 PM CDT | Lake Wind Advisory | JAN | 39 hr |
| Apr 12, 3:45 AM CDT | Lake Wind Advisory | JAN | 19 hr |
| Apr 12, 1:02 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Apr 12, 1:53 PM CDT | Tornado Watch | SPC | 7 hr |
| Apr 12, 5:06 PM CDT | Severe Thunderstorm Warning | JAN | 39 min |
| Apr 12, 5:40 PM CDT | Severe Thunderstorm Warning | JAN | 50 min |
| Apr 12, 5:49 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Apr 13, 6:18 AM CDT | Dense Fog Advisory | JAN | 81 min |
| Apr 13, 1:39 PM CDT | Mesoscale Discussion | SPC | 66 min |
| May 3, 6:54 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 3, 7:44 AM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| May 3, 8:54 AM CDT | Severe Thunderstorm Warning | JAN | 66 min |
| May 3, 9:19 AM CDT | Tornado Warning | JAN | 56 min |
| May 3, 9:24 AM CDT | Mesoscale Discussion | SPC | 66 min |
| May 3, 9:40 AM CDT | Severe Thunderstorm Warning | JAN | 65 min |
| May 5, 4:24 AM CDT | Flash Flood Watch | JAN | 36 hr |
| May 5, 11:27 AM CDT | River Flood Advisory | JAN | 24 hr |
| May 5, 9:36 PM CDT | River Flood Warning | JAN | 32 days |
| May 6, 11:34 AM CDT | Mesoscale Discussion | SPC | 86 min |
| May 6, 12:37 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 6, 1:48 PM CDT | Severe Thunderstorm Warning | JAN | 42 min |
| May 10, 1:29 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 10, 3:48 PM CDT | Mesoscale Discussion | SPC | 87 min |
| May 10, 7:50 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| May 11, 5:25 AM CDT | Flash Flood Watch | JAN | 12 hr |
| May 11, 2:20 PM CDT | Mesoscale Discussion | SPC | 55 min |
| May 11, 2:52 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jun 21, 4:04 AM CDT | Heat Advisory | JAN | 4 days |
| Jun 24, 1:28 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jun 27, 4:48 AM CDT | Heat Advisory | JAN | 38 hr |
| Jul 4, 3:20 AM CDT | Heat Advisory | JAN | 24 hr |
| Jul 12, 8:25 PM CDT | Heat Advisory | JAN | 32 hr |
| Jul 15, 5:55 PM CDT | Severe Thunderstorm Warning | JAN | 25 min |
| Jul 15, 6:52 PM CDT | Severe Thunderstorm Warning | JAN | 38 min |
| Jul 26, 9:45 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 28, 11:25 AM CDT | Mesoscale Discussion | SPC | 65 min |
| Jul 30, 10:12 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 30, 2:02 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Aug 5, 7:57 AM CDT | Mesoscale Discussion | SPC | 93 min |
| Aug 6, 8:55 AM CDT | Severe Thunderstorm Warning | JAN | 65 min |
| Aug 6, 9:36 AM CDT | Severe Thunderstorm Warning | JAN | 39 min |
| Aug 6, 10:11 AM CDT | Mesoscale Discussion | SPC | 94 min |
| Aug 21, 3:53 PM CDT | Severe Thunderstorm Warning | JAN | 67 min |
| Aug 29, 10:50 PM CDT | Flash Flood Warning | JAN | 115 min |
| Sep 22, 3:59 AM CDT | Flash Flood Watch | JAN | 15 hr |
| Sep 23, 4:29 PM CDT | Flash Flood Warning | JAN | 2 hr |
| Sep 23, 5:33 PM CDT | Flash Flood Warning | JAN | 91 min |
| Sep 24, 4:03 AM CDT | Flash Flood Watch | JAN | 12 hr |
| Oct 1, 10:24 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Oct 4, 3:48 AM CDT | Flash Flood Watch | JAN | 17 hr |
| Oct 8, 4:32 AM CDT | Dense Fog Advisory | JAN | 4 hr |
| Oct 8, 2:57 PM CDT | Lake Wind Advisory | JAN | 25 hr |
| Oct 14, 12:14 PM CDT | River Flood Advisory | JAN | 34 hr |
| Oct 15, 7:08 AM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Oct 15, 10:23 AM CDT | Mesoscale Discussion | SPC | 67 min |
| Oct 15, 12:31 PM CDT | Mesoscale Discussion | SPC | 29 min |
| Oct 15, 12:53 PM CDT | Tornado Warning | JAN | 54 min |
| Oct 15, 1:23 PM CDT | Severe Thunderstorm Warning | JAN | 52 min |
| Oct 16, 11:33 AM CDT | River Flood Advisory | JAN | 36 hr |
| Oct 18, 10:32 AM CDT | River Flood Advisory | JAN | 36 hr |
| Oct 20, 3:11 PM CDT | River Flood Advisory | JAN | 69 hr |
| Oct 21, 4:07 PM CDT | Flash Flood Watch | JAN | 30 hr |
| Oct 22, 11:27 AM CDT | Mesoscale Discussion | SPC | 93 min |
| Oct 22, 11:58 AM CDT | Tornado Watch | SPC | 7 hr |
| Oct 22, 3:36 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Oct 22, 6:26 PM CDT | Mesoscale Discussion | SPC | 34 min |
| Oct 22, 6:55 PM CDT | Severe Thunderstorm Warning | JAN | 65 min |
| Oct 27, 3:35 PM CDT | Dense Fog Advisory | JAN | 18 hr |
| Oct 30, 2:03 AM CDT | Mesoscale Discussion | SPC | 57 min |
| Oct 30, 10:22 AM CDT | Mesoscale Discussion | SPC | 83 min |
| Oct 30, 11:53 PM CDT | River Flood Advisory | JAN | 36 hr |
| Nov 1, 7:26 PM CST | River Flood Advisory | JAN | 36 hr |
| Nov 3, 11:09 AM CST | River Flood Advisory | JAN | 36 hr |
| Nov 4, 3:36 AM CST | Dense Fog Advisory | JAN | 4 hr |
| Nov 5, 12:12 PM CST | River Flood Advisory | JAN | 36 hr |
| Nov 7, 11:24 AM CST | River Flood Advisory | JAN | 36 hr |
| Nov 9, 11:23 AM CST | River Flood Advisory | JAN | 36 hr |
| Nov 9, 3:54 PM CST | Lake Wind Advisory | JAN | 25 hr |
| Nov 12, 11:56 AM CST | River Flood Advisory | JAN | 36 hr |
| Nov 24, 3:03 AM CST | Dense Fog Advisory | JAN | 6 hr |
| Nov 26, 4:39 AM CST | Freeze Warning | JAN | 27 hr |
| Dec 3, 3:49 PM CST | Winter Storm Watch | JAN | 12 hr |
| Dec 4, 4:00 AM CST | Winter Weather Advisory | JAN | 23 hr |
| Dec 4, 10:20 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Dec 4, 12:13 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Dec 4, 5:22 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Dec 7, 3:19 PM CST | Lake Wind Advisory | JAN | 48 hr |
| Dec 8, 12:12 PM CST | Mesoscale Discussion | SPC | 93 min |
| Dec 8, 1:25 PM CST | Tornado Watch | SPC | 8 hr |
| Dec 8, 8:33 PM CST | Tornado Watch | SPC | 5 hr |
| Dec 13, 3:37 PM CST | Dense Fog Advisory | JAN | 17 hr |
| Dec 13, 3:49 PM CST | Flash Flood Watch | JAN | 47 hr |
| Dec 14, 10:08 AM CST | Mesoscale Discussion | SPC | 3 hr |
| Dec 14, 3:18 PM CST | Flash Flood Warning | JAN | 3 hr |
| Dec 22, 3:28 PM CST | Lake Wind Advisory | JAN | 43 hr |
| Dec 23, 4:31 AM CST | Flash Flood Watch | JAN | 37 hr |
| Dec 23, 3:03 PM CST | Wind Advisory | JAN | 36 hr |
| Dec 24, 3:30 AM CST | Mesoscale Discussion | SPC | 2 hr |
| Dec 24, 4:50 AM CST | Tornado Watch | SPC | 7 hr |
| Dec 24, 7:30 AM CST | Mesoscale Discussion | SPC | 90 min |
| Dec 24, 9:34 AM CST | Mesoscale Discussion | SPC | 56 min |
| Dec 24, 9:45 AM CST | Severe Thunderstorm Warning | JAN | 60 min |
| Dec 24, 10:13 AM CST | Mesoscale Discussion | SPC | 62 min |
| Dec 24, 10:40 AM CST | Severe Thunderstorm Warning | JAN | 65 min |
| Dec 24, 5:00 PM CST | Lake Wind Advisory | JAN | 21 hr |
| Dec 30, 5:30 PM CST | Dense Fog Advisory | JAN | 15 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 | 20 |
| Tornado Warning | 4 |
| Severe Thunderstorm Watch | 9 |
| Tornado Watch | 10 |
| Mesoscale Discussion | 45 |
| Flooding | |
| Flash Flood Warning | 5 |
| River Flood Warning | 1 |
| Flash Flood Watch | 12 |
| Flood Watch | 1 |
| River Flood Advisory | 12 |
| Winter | |
| Winter Storm Watch | 1 |
| Winter Weather Advisory | 1 |
| Heat | |
| Heat Advisory | 4 |
| Cold | |
| Freeze Warning | 2 |
| Hard Freeze Warning | 1 |
| Freeze Watch | 1 |
| Hard Freeze Watch | 1 |
| Wind and dust | |
| Lake Wind Advisory | 19 |
| Wind Advisory | 2 |
| Fog and smoke | |
| Dense Fog Advisory | 9 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20082010
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.