Alert archive / Missouri / Jefferson County
Weather alerts in Jefferson County, Missouri, 2023
132 weather alerts in 2023, 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 2023. Tap one for its archive.
- Alerts
- 132
- Warnings
- 55
- Watches
- 27
- Advisories
- 16
- Busiest month
- July29 alerts
- Busiest day
- April 15, 202311 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 2 tornado warnings covering Jefferson County in 2023 had a tornado report inside them; 7 of 7 tornado reports fell inside a warning, on average 10 minutes after it went out.
Jefferson County, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 2 | 2 | 0% | 7 | 100% | 10 min |
| Severe thunderstorm warnings | 30 | 25 | 17% | 49 | 76% | 23 min |
| Flash flood warnings | 2 | 2 | 0% | 0 |
Each office's whole area, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS St. Louis, MO: tornado warnings | 33 | 8 | 76% | 25 | 76% | 11 min |
| NWS St. Louis, MO: severe thunderstorm warnings | 380 | 218 | 43% | 1,082 | 84% | 22 min |
| NWS St. Louis, MO: flash flood warnings | 38 | 22 | 42% | 44 | 77% | 100 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, 11:43 PM CST | Dense Fog Advisory | LSX | 15 hr |
| Jan 22, 2:06 PM CST | Winter Storm Watch | LSX | 24 hr |
| Jan 23, 2:12 PM CST | Winter Storm Warning | LSX | 43 hr |
| Jan 29, 1:30 PM CST | Winter Weather Advisory | LSX | 20 hr |
| Feb 13, 2:12 PM CST | Wind Advisory | LSX | 30 hr |
| Feb 16, 2:44 AM CST | Severe Thunderstorm Warning | LSX | 46 min |
| Feb 22, 12:04 PM CST | Mesoscale Discussion | SPC | 56 min |
| Feb 22, 12:20 PM CST | Tornado Watch | SPC | 5 hr |
| Feb 22, 1:53 PM CST | Severe Thunderstorm Warning | LSX | 52 min |
| Feb 26, 1:27 AM CST | Wind Advisory | LSX | 41 hr |
| Feb 27, 1:43 AM CST | Mesoscale Discussion | SPC | 62 min |
| Mar 1, 1:36 PM CST | Flood Watch | LSX | 46 hr |
| Mar 2, 2:42 AM CST | Wind Advisory | LSX | 39 hr |
| Mar 3, 9:34 AM CST | River Flood Warning | LSX | 68 hr |
| Mar 3, 11:49 AM CST | River Flood Warning | LSX | 5 days |
| Mar 3, 11:49 AM CST | River Flood Warning | LSX | 4 days |
| Mar 3, 11:49 AM CST | River Flood Warning | LSX | 6 days |
| Mar 22, 1:39 PM CDT | Flood Watch | LSX | 54 hr |
| Mar 23, 10:18 AM CDT | River Flood Warning | LSX | 21 days |
| Mar 23, 10:18 AM CDT | River Flood Warning | LSX | 7 days |
| Mar 23, 10:18 AM CDT | River Flood Warning | LSX | 6 days |
| Mar 23, 10:18 AM CDT | River Flood Warning | LSX | 21 days |
| Mar 23, 10:18 AM CDT | River Flood Warning | LSX | 6 days |
| Mar 23, 11:57 AM CDT | River Flood Warning | LSX | 4 days |
| Mar 30, 3:03 AM CDT | Wind Advisory | LSX | 58 hr |
| Mar 31, 8:36 AM CDT | Mesoscale Discussion | SPC | 84 min |
| Mar 31, 11:24 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Mar 31, 12:28 PM CDT | Tornado Watch | SPC | 11 hr |
| Mar 31, 12:53 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Mar 31, 6:24 PM CDT | Severe Thunderstorm Warning | LSX | 23 min |
| Mar 31, 7:38 PM CDT | Severe Thunderstorm Warning | LSX | 52 min |
| Apr 3, 2:28 PM CDT | Wind Advisory | LSX | 41 hr |
| Apr 5, 2:27 AM CDT | Severe Thunderstorm Watch | SPC | 10 hr |
| Apr 5, 8:00 AM CDT | Severe Thunderstorm Warning | LSX | 45 min |
| Apr 5, 8:41 AM CDT | Severe Thunderstorm Warning | LSX | 49 min |
| Apr 5, 9:11 AM CDT | Severe Thunderstorm Warning | LSX | 26 min |
| Apr 6, 2:41 PM CDT | Frost Advisory | LSX | 18 hr |
| Apr 15, 8:50 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Apr 15, 11:39 AM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 15, 3:21 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Apr 15, 4:03 PM CDT | Tornado Watch | SPC | 6 hr |
| Apr 15, 5:07 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Apr 15, 5:52 PM CDT | Severe Thunderstorm Warning | LSX | 38 min |
| Apr 15, 6:07 PM CDT | Tornado Warning | LSX | 35 min |
| Apr 15, 6:23 PM CDT | Severe Thunderstorm Warning | LSX | 53 min |
| Apr 15, 6:27 PM CDT | Severe Thunderstorm Warning | LSX | 52 min |
| Apr 15, 6:34 PM CDT | Tornado Warning | LSX | 41 min |
| Apr 15, 6:39 PM CDT | Flash Flood Warning | LSX | 4 hr |
| Apr 20, 12:25 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 20, 1:20 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Apr 20, 3:10 PM CDT | Mesoscale Discussion | SPC | 95 min |
| Apr 20, 5:36 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Apr 22, 3:57 AM CDT | Frost Advisory | LSX | 29 hr |
| Apr 22, 2:45 PM CDT | Freeze Watch | LSX | 12 hr |
| Apr 23, 2:41 AM CDT | Freeze Warning | LSX | 29 hr |
| May 7, 1:18 PM CDT | Severe Thunderstorm Watch | SPC | 10 hr |
| May 8, 4:55 AM CDT | Severe Thunderstorm Warning | LSX | 35 min |
| May 8, 2:16 PM CDT | Mesoscale Discussion | SPC | 59 min |
| May 8, 3:19 PM CDT | Severe Thunderstorm Watch | SPC | 10 hr |
| May 8, 5:36 PM CDT | Mesoscale Discussion | SPC | 84 min |
| May 8, 9:05 PM CDT | Mesoscale Discussion | SPC | 115 min |
| May 13, 12:24 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 13, 2:38 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 13, 2:45 PM CDT | Severe Thunderstorm Warning | LSX | 45 min |
| May 13, 5:16 PM CDT | Areal Flood Advisory | LSX | 104 min |
| May 13, 6:09 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 14, 12:43 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| May 14, 2:59 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 14, 5:47 PM CDT | Mesoscale Discussion | SPC | 88 min |
| May 15, 2:07 PM CDT | Flood Watch | LSX | 16 hr |
| Jun 18, 5:22 PM CDT | Areal Flood Advisory | LSX | 15 min |
| Jun 18, 5:37 PM CDT | Flash Flood Warning | LSX | 3 hr |
| Jun 28, 3:02 AM CDT | Heat Advisory | LSX | 64 hr |
| Jun 30, 2:32 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 30, 3:53 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 30, 6:05 PM CDT | Severe Thunderstorm Warning | LSX | 40 min |
| Jun 30, 6:31 PM CDT | Severe Thunderstorm Warning | LSX | 59 min |
| Jun 30, 7:58 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Jul 1, 12:04 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jul 1, 2:15 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Jul 1, 2:59 PM CDT | Severe Thunderstorm Warning | LSX | 46 min |
| Jul 1, 4:00 PM CDT | Severe Thunderstorm Warning | LSX | 38 min |
| Jul 2, 12:28 AM CDT | Severe Thunderstorm Warning | LSX | 32 min |
| Jul 12, 4:59 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Jul 16, 1:24 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 16, 2:21 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Jul 16, 3:06 PM CDT | Severe Thunderstorm Warning | LSX | 39 min |
| Jul 16, 3:19 PM CDT | Severe Thunderstorm Warning | LSX | 41 min |
| Jul 16, 3:45 PM CDT | Severe Thunderstorm Warning | LSX | 27 min |
| Jul 17, 1:28 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jul 17, 6:23 PM CDT | Severe Thunderstorm Warning | LSX | 40 min |
| Jul 18, 8:42 AM CDT | Mesoscale Discussion | SPC | 93 min |
| Jul 18, 8:59 AM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jul 18, 11:41 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 19, 3:55 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 20, 8:58 AM CDT | Mesoscale Discussion | SPC | 92 min |
| Jul 23, 4:58 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 25, 1:09 PM CDT | Heat Advisory | LSX | 4 days |
| Jul 26, 11:59 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 27, 3:05 AM CDT | Excessive Heat Warning | LSX | 62 hr |
| Jul 29, 11:04 AM CDT | Mesoscale Discussion | SPC | 116 min |
| Jul 29, 11:28 AM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 29, 2:18 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Jul 29, 3:24 PM CDT | Severe Thunderstorm Warning | LSX | 36 min |
| Jul 29, 3:57 PM CDT | Severe Thunderstorm Warning | LSX | 48 min |
| Jul 29, 4:16 PM CDT | Severe Thunderstorm Warning | LSX | 44 min |
| Aug 2, 2:56 AM CDT | Flood Watch | LSX | 31 hr |
| Aug 2, 5:30 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 2, 7:58 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 3, 4:52 AM CDT | Severe Thunderstorm Warning | LSX | 38 min |
| Aug 3, 10:40 AM CDT | River Flood Warning | LSX | 4 days |
| Aug 3, 10:40 AM CDT | River Flood Warning | LSX | 4 days |
| Aug 3, 7:04 PM CDT | Flood Watch | LSX | 14 hr |
| Aug 4, 10:05 AM CDT | River Flood Warning | LSX | 3 days |
| Aug 4, 5:17 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 4, 11:22 PM CDT | Severe Thunderstorm Warning | LSX | 38 min |
| Aug 5, 2:25 AM CDT | Areal Flood Advisory | LSX | 3 hr |
| Aug 5, 9:12 PM CDT | River Flood Warning | LSX | 49 hr |
| Aug 10, 1:05 AM CDT | Dense Fog Advisory | LSX | 8 hr |
| Aug 12, 1:42 AM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 12, 4:08 AM CDT | Severe Thunderstorm Warning | LSX | 67 min |
| Aug 12, 4:46 AM CDT | Severe Thunderstorm Warning | LSX | 59 min |
| Aug 12, 5:16 AM CDT | Mesoscale Discussion | SPC | 89 min |
| Aug 18, 2:51 AM CDT | Excessive Heat Watch | LSX | 25 hr |
| Aug 19, 3:24 AM CDT | Excessive Heat Warning | LSX | 7 days |
| Aug 23, 4:50 AM CDT | Dense Fog Advisory | LSX | 3 hr |
| Sep 26, 9:07 PM CDT | Severe Thunderstorm Warning | LSX | 38 min |
| Sep 26, 9:38 PM CDT | Severe Thunderstorm Warning | LSX | 52 min |
| Oct 21, 3:05 AM CDT | Red Flag Warning | LSX | 16 hr |
| Oct 27, 4:16 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Oct 28, 2:16 PM CDT | Freeze Warning | LSX | 44 hr |
| Oct 30, 9:57 AM CDT | Freeze Warning | LSX | 24 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 | 30 |
| Tornado Warning | 2 |
| Severe Thunderstorm Watch | 16 |
| Tornado Watch | 3 |
| Mesoscale Discussion | 34 |
| Flooding | |
| Flash Flood Warning | 2 |
| River Flood Warning | 14 |
| Flood Watch | 5 |
| Areal Flood Advisory | 3 |
| Winter | |
| Winter Storm Warning | 1 |
| Winter Storm Watch | 1 |
| Winter Weather Advisory | 1 |
| Heat | |
| Excessive Heat Warning | 2 |
| Excessive Heat Watch | 1 |
| Heat Advisory | 2 |
| Cold | |
| Freeze Warning | 3 |
| Freeze Watch | 1 |
| Frost Advisory | 2 |
| Wind and dust | |
| Wind Advisory | 5 |
| Fire | |
| Red Flag Warning | 1 |
| Fog and smoke | |
| Dense Fog Advisory | 3 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20222024
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.