Alert archive / Missouri / Jefferson County
Weather alerts in Jefferson County, Missouri, 2019
170 weather alerts in 2019, 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 2019. Tap one for its archive.
- Alerts
- 170
- Warnings
- 59
- Watches
- 31
- Advisories
- 36
- Busiest month
- May37 alerts
- Busiest day
- May 1, 201911 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 4 tornado warnings covering Jefferson County in 2019 had a tornado report inside them.
Jefferson County, 2019
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 4 | 1 | 75% | 0 | ||
| Severe thunderstorm warnings | 23 | 12 | 48% | 10 | 60% | 22 min |
| Flash flood warnings | 5 | 5 | 0% | 1 | 100% | 92 min |
Each office's whole area, 2019
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS St. Louis, MO: tornado warnings | 49 | 9 | 82% | 29 | 59% | 23 min |
| NWS St. Louis, MO: severe thunderstorm warnings | 241 | 129 | 46% | 389 | 76% | 24 min |
| NWS St. Louis, MO: flash flood warnings | 55 | 31 | 44% | 127 | 94% | 128 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, 10:27 AM CST | River Flood Warning | LSX | 50 hr |
| Jan 10, 3:33 AM CST | Winter Storm Watch | LSX | 12 hr |
| Jan 10, 3:31 PM CST | Winter Storm Warning | LSX | 62 hr |
| Jan 11, 10:37 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Jan 11, 6:15 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Jan 15, 3:12 PM CST | Winter Weather Advisory | LSX | 19 hr |
| Jan 17, 4:10 AM CST | Dense Fog Advisory | LSX | 8 hr |
| Jan 18, 2:45 AM CST | Winter Weather Advisory | LSX | 41 hr |
| Jan 28, 3:00 AM CST | Wind Chill Watch | LSX | 13 hr |
| Jan 28, 3:49 PM CST | Wind Chill Advisory | LSX | 44 hr |
| Jan 30, 3:47 AM CST | Winter Weather Advisory | LSX | 19 hr |
| Jan 31, 2:41 PM CST | Winter Weather Advisory | LSX | 12 hr |
| Feb 2, 3:34 AM CST | Dense Fog Advisory | LSX | 8 hr |
| Feb 6, 8:50 PM CST | Dense Fog Advisory | LSX | 9 hr |
| Feb 7, 8:32 PM CST | River Flood Warning | LSX | 47 hr |
| Feb 7, 8:32 PM CST | River Flood Warning | LSX | 4 days |
| Feb 7, 8:32 PM CST | River Flood Warning | LSX | 4 days |
| Feb 9, 3:17 AM CST | Winter Weather Advisory | LSX | 35 hr |
| Feb 10, 1:15 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Feb 14, 3:01 PM CST | Winter Weather Advisory | LSX | 32 hr |
| Feb 16, 3:25 AM CST | Winter Weather Advisory | LSX | 39 hr |
| Feb 18, 3:20 PM CST | Winter Weather Advisory | LSX | 44 hr |
| Feb 20, 9:09 AM CST | Dense Fog Advisory | LSX | 3 hr |
| Feb 22, 3:45 PM CST | Wind Advisory | LSX | 50 hr |
| Feb 27, 3:16 AM CST | Winter Weather Advisory | LSX | 39 hr |
| Mar 1, 3:36 AM CST | Winter Storm Watch | LSX | 24 hr |
| Mar 2, 3:37 AM CST | Winter Weather Advisory | LSX | 35 hr |
| Mar 8, 3:03 PM CST | Wind Advisory | LSX | 33 hr |
| Mar 9, 3:17 PM CST | Mesoscale Discussion | SPC | 118 min |
| Mar 12, 11:06 AM CDT | River Flood Warning | LSX | 140 days |
| Mar 12, 3:30 PM CDT | Wind Advisory | LSX | 28 hr |
| Mar 13, 3:42 AM CDT | High Wind Watch | LSX | 24 hr |
| Mar 14, 3:33 AM CDT | High Wind Warning | LSX | 18 hr |
| Mar 24, 1:53 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Mar 24, 2:52 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Mar 24, 5:11 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Mar 24, 5:28 PM CDT | Tornado Warning | LSX | 47 min |
| Mar 24, 8:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Mar 29, 10:29 AM CDT | River Flood Warning | LSX | 9 days |
| Mar 29, 10:33 AM CDT | River Flood Warning | LSX | 8 days |
| Apr 7, 3:14 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 7, 7:18 PM CDT | Special Weather Statement | LSX | 42 min |
| Apr 10, 3:37 PM CDT | Wind Advisory | LSX | 27 hr |
| Apr 14, 3:30 AM CDT | Frost Advisory | LSX | 30 hr |
| Apr 18, 2:16 AM CDT | Mesoscale Discussion | SPC | 119 min |
| Apr 25, 1:33 AM CDT | Dense Fog Advisory | LSX | 8 hr |
| Apr 29, 3:28 PM CDT | Flash Flood Watch | LSX | 3 days |
| Apr 30, 11:21 AM CDT | River Flood Warning | LSX | 17 days |
| Apr 30, 12:39 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 30, 12:58 PM CDT | Severe Thunderstorm Warning | LSX | 14 min |
| Apr 30, 1:00 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Apr 30, 4:35 PM CDT | Mesoscale Discussion | SPC | 55 min |
| Apr 30, 7:29 PM CDT | Mesoscale Discussion | SPC | 61 min |
| Apr 30, 8:03 PM CDT | Tornado Watch | SPC | 5 hr |
| Apr 30, 10:01 PM CDT | Areal Flood Warning | LSX | 24 hr |
| Apr 30, 10:13 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Apr 30, 11:05 PM CDT | Severe Thunderstorm Warning | LSX | 40 min |
| Apr 30, 11:29 PM CDT | Tornado Warning | LSX | 31 min |
| Apr 30, 11:44 PM CDT | Severe Thunderstorm Warning | LSX | 46 min |
| Apr 30, 11:52 PM CDT | Tornado Warning | LSX | 23 min |
| May 1, 9:15 AM CDT | River Flood Warning | LSX | 5 days |
| May 1, 9:15 AM CDT | River Flood Warning | LSX | 4 days |
| May 1, 11:59 AM CDT | River Flood Warning | LSX | 15 days |
| May 2, 12:52 PM CDT | Areal Flood Advisory | LSX | 3 hr |
| May 5, 7:06 AM CDT | River Flood Warning | LSX | 14 hr |
| May 15, 12:10 AM CDT | Special Weather Statement | LSX | 50 min |
| May 15, 12:14 AM CDT | Severe Thunderstorm Warning | LSX | 46 min |
| May 18, 4:40 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| May 18, 7:07 PM CDT | Special Weather Statement | LSX | 23 min |
| May 18, 7:19 PM CDT | Mesoscale Discussion | SPC | 116 min |
| May 21, 12:55 AM CDT | Mesoscale Discussion | SPC | 95 min |
| May 21, 1:32 AM CDT | Special Weather Statement | LSX | 43 min |
| May 21, 3:40 AM CDT | Flash Flood Watch | LSX | 20 hr |
| May 21, 11:18 AM CDT | River Flood Warning | LSX | 42 days |
| May 21, 11:18 AM CDT | River Flood Warning | LSX | 41 days |
| May 21, 3:10 PM CDT | Tornado Watch | SPC | 8 hr |
| May 21, 5:43 PM CDT | Mesoscale Discussion | SPC | 62 min |
| May 21, 5:59 PM CDT | Severe Thunderstorm Warning | LSX | 76 min |
| May 21, 6:32 PM CDT | Severe Thunderstorm Warning | LSX | 88 min |
| May 21, 6:48 PM CDT | Tornado Warning | LSX | 42 min |
| May 21, 7:37 PM CDT | Mesoscale Discussion | SPC | 83 min |
| May 22, 5:40 PM CDT | River Flood Warning | LSX | 3 days |
| May 22, 10:26 PM CDT | Tornado Watch | SPC | 8 hr |
| May 23, 1:23 AM CDT | Mesoscale Discussion | SPC | 97 min |
| May 23, 2:54 AM CDT | Severe Thunderstorm Warning | LSX | 51 min |
| May 23, 3:41 AM CDT | Severe Thunderstorm Warning | LSX | 49 min |
| May 23, 4:37 AM CDT | Areal Flood Warning | LSX | 3 hr |
| May 29, 3:48 PM CDT | Mesoscale Discussion | SPC | 87 min |
| May 29, 4:34 PM CDT | Severe Thunderstorm Watch | SPC | 3 hr |
| Jun 1, 3:33 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 1, 6:07 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 1, 7:18 PM CDT | Mesoscale Discussion | SPC | 57 min |
| Jun 1, 8:10 PM CDT | Severe Thunderstorm Warning | LSX | 65 min |
| Jun 1, 10:24 PM CDT | Severe Thunderstorm Warning | LSX | 37 min |
| Jun 4, 2:52 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 4, 4:57 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Jun 4, 5:42 PM CDT | Severe Thunderstorm Warning | LSX | 48 min |
| Jun 4, 6:44 PM CDT | Severe Thunderstorm Warning | LSX | 46 min |
| Jun 5, 2:21 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 5, 2:44 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 5, 6:01 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Jun 5, 7:03 PM CDT | Severe Thunderstorm Warning | LSX | 42 min |
| Jun 5, 7:44 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Jun 17, 3:16 AM CDT | Flash Flood Watch | LSX | 17 hr |
| Jun 21, 8:28 AM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 21, 10:50 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Jun 22, 9:08 AM CDT | Areal Flood Advisory | LSX | 3 hr |
| Jun 26, 1:06 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Jun 28, 11:23 AM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 28, 5:00 PM CDT | Special Weather Statement | LSX | 45 min |
| Jul 9, 1:32 PM CDT | Heat Advisory | LSX | 29 hr |
| Jul 15, 4:24 PM CDT | Excessive Heat Watch | LSX | 23 hr |
| Jul 16, 3:32 PM CDT | Excessive Heat Warning | LSX | 5 days |
| Jul 17, 5:17 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Jul 17, 6:01 PM CDT | Severe Thunderstorm Warning | LSX | 44 min |
| Jul 17, 6:17 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jul 17, 6:37 PM CDT | Severe Thunderstorm Warning | LSX | 18 min |
| Jul 22, 4:24 AM CDT | Flash Flood Warning | LSX | 6 hr |
| Jul 22, 9:58 AM CDT | Areal Flood Warning | LSX | 6 hr |
| Aug 6, 1:08 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 6, 1:49 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 6, 2:28 PM CDT | Special Weather Statement | LSX | 62 min |
| Aug 6, 2:36 PM CDT | Severe Thunderstorm Warning | LSX | 39 min |
| Aug 6, 3:47 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Aug 11, 3:43 AM CDT | Heat Advisory | LSX | 41 hr |
| Aug 11, 9:17 PM CDT | Flash Flood Watch | LSX | 13 hr |
| Aug 13, 5:36 AM CDT | Areal Flood Advisory | LSX | 3 hr |
| Aug 18, 1:05 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 20, 6:18 AM CDT | Severe Thunderstorm Watch | SPC | 11 hr |
| Aug 21, 3:06 PM CDT | Flash Flood Watch | LSX | 19 hr |
| Aug 21, 9:53 PM CDT | Flash Flood Warning | LSX | 8 hr |
| Aug 26, 6:21 AM CDT | Flash Flood Warning | LSX | 4 hr |
| Aug 26, 10:28 AM CDT | Areal Flood Advisory | LSX | 3 hr |
| Aug 26, 2:24 PM CDT | Mesoscale Discussion | SPC | 66 min |
| Aug 26, 2:51 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Aug 26, 3:04 PM CDT | Severe Thunderstorm Warning | LSX | 42 min |
| Aug 30, 2:26 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 30, 3:44 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Aug 30, 4:08 PM CDT | Severe Thunderstorm Warning | LSX | 67 min |
| Aug 30, 5:02 PM CDT | Flash Flood Warning | LSX | 3 hr |
| Aug 30, 5:15 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Aug 30, 5:17 PM CDT | Severe Thunderstorm Warning | LSX | 43 min |
| Aug 30, 5:41 PM CDT | Flash Flood Warning | LSX | 6 hr |
| Aug 30, 6:34 PM CDT | Severe Thunderstorm Warning | LSX | 41 min |
| Aug 30, 7:10 PM CDT | Severe Thunderstorm Warning | LSX | 50 min |
| Aug 30, 7:53 PM CDT | Areal Flood Warning | LSX | 12 hr |
| Aug 30, 8:10 PM CDT | Areal Flood Advisory | LSX | 6 hr |
| Sep 1, 9:41 PM CDT | Dense Fog Advisory | LSX | 12 hr |
| Sep 8, 8:09 AM CDT | Special Weather Statement | LSX | 66 min |
| Sep 10, 3:12 AM CDT | Heat Advisory | LSX | 64 hr |
| Sep 30, 10:25 AM CDT | River Flood Warning | LSX | 28 days |
| Oct 11, 2:42 PM CDT | Frost Advisory | LSX | 17 hr |
| Oct 21, 3:06 AM CDT | Tornado Watch | SPC | 6 hr |
| Oct 21, 3:44 AM CDT | Severe Thunderstorm Warning | LSX | 46 min |
| Oct 27, 1:54 AM CDT | Dense Fog Advisory | LSX | 8 hr |
| Oct 30, 3:23 AM CDT | Freeze Warning | LSX | 31 hr |
| Oct 30, 9:57 AM CDT | River Flood Warning | LSX | 6 days |
| Nov 10, 2:57 PM CST | Winter Weather Advisory | LSX | 28 hr |
| Nov 26, 3:22 AM CST | Wind Advisory | LSX | 33 hr |
| Nov 26, 1:04 PM CST | High Wind Warning | LSX | 23 hr |
| Nov 26, 6:20 PM CST | Tornado Watch | SPC | 6 hr |
| Nov 29, 9:24 PM CST | Severe Thunderstorm Warning | LSX | 51 min |
| Nov 30, 2:23 PM CST | Wind Advisory | LSX | 28 hr |
| Dec 14, 3:54 AM CST | Winter Storm Watch | LSX | 24 hr |
| Dec 15, 3:35 AM CST | Winter Storm Warning | LSX | 44 hr |
| Dec 15, 10:05 AM CST | Mesoscale Discussion | SPC | 4 hr |
| Dec 15, 2:11 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Dec 16, 4:24 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Dec 16, 10:36 AM CST | Mesoscale Discussion | SPC | 4 hr |
| Dec 28, 4:30 AM CST | Dense Fog Advisory | LSX | 7 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20182020
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.