Alert archive / Iowa / Louisa County
Weather alerts in Louisa County, Iowa, 2023
122 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Louisa County and its neighbors
Each county as a circle sized by its count in 2023. Tap one for its archive.
- Alerts
- 122
- Warnings
- 37
- Watches
- 19
- Advisories
- 32
- Busiest month
- April26 alerts
- Busiest day
- May 7, 202314 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 Louisa County in 2023 had a tornado report inside them.
Louisa County, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 2 | 1 | 50% | 0 | ||
| Severe thunderstorm warnings | 21 | 14 | 33% | 1 | 100% | 6 min |
| Flash flood warnings | 1 | 0 | 100% | 0 |
Each office's whole area, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Quad Cities, IA: tornado warnings | 62 | 26 | 58% | 67 | 67% | 15 min |
| NWS Quad Cities, IA: severe thunderstorm warnings | 233 | 149 | 36% | 582 | 87% | 25 min |
| NWS Quad Cities, IA: flash flood warnings | 15 | 3 | 80% | 10 | 80% | 170 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, 5:13 PM CST | Dense Fog Advisory | DVN | 25 hr |
| Jan 3, 5:14 AM CST | Dense Fog Advisory | DVN | 17 hr |
| Jan 19, 7:44 AM CST | Dense Fog Advisory | DVN | 3 hr |
| Jan 24, 1:54 AM CST | Winter Weather Advisory | DVN | 36 hr |
| Feb 8, 2:45 PM CST | Winter Weather Advisory | DVN | 26 hr |
| Feb 9, 9:48 AM CST | Mesoscale Discussion | SPC | 4 hr |
| Feb 9, 11:43 AM CST | Special Weather Statement | DVN | 62 min |
| Feb 13, 1:51 PM CST | Wind Advisory | DVN | 29 hr |
| Feb 14, 2:08 PM CST | Winter Storm Watch | DVN | 13 hr |
| Feb 15, 3:18 AM CST | Winter Storm Warning | DVN | 42 hr |
| Feb 15, 3:18 AM CST | Winter Weather Advisory | DVN | 42 hr |
| Feb 27, 8:06 PM CST | River Flood Warning | DVN | 8 days |
| Mar 1, 8:36 PM CST | River Flood Watch | DVN | 6 days |
| Mar 4, 10:26 PM CST | Dense Fog Advisory | DVN | 9 hr |
| Mar 8, 3:04 PM CST | Winter Weather Advisory | DVN | 37 hr |
| Mar 22, 8:53 PM CDT | Special Weather Statement | DVN | 37 min |
| Mar 24, 2:56 AM CDT | Winter Weather Advisory | DVN | 32 hr |
| Mar 31, 3:11 AM CDT | Wind Advisory | DVN | 34 hr |
| Mar 31, 10:37 AM CDT | Mesoscale Discussion | SPC | 53 min |
| Mar 31, 11:24 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Mar 31, 11:46 AM CDT | Tornado Watch | SPC | 8 hr |
| Mar 31, 2:07 PM CDT | Severe Thunderstorm Warning | DVN | 38 min |
| Mar 31, 2:15 PM CDT | Severe Thunderstorm Warning | DVN | 45 min |
| Mar 31, 3:17 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Mar 31, 4:35 PM CDT | Tornado Warning | DVN | 25 min |
| Mar 31, 5:18 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Mar 31, 5:22 PM CDT | Severe Thunderstorm Warning | DVN | 38 min |
| Mar 31, 5:30 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Mar 31, 5:54 PM CDT | Tornado Warning | DVN | 26 min |
| Apr 4, 8:00 AM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 4, 8:11 AM CDT | Severe Thunderstorm Warning | DVN | 49 min |
| Apr 4, 1:49 PM CDT | Mesoscale Discussion | SPC | 116 min |
| Apr 4, 2:48 PM CDT | Tornado Watch | SPC | 7 hr |
| Apr 4, 6:18 PM CDT | Mesoscale Discussion | SPC | 87 min |
| Apr 4, 9:58 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Apr 5, 1:50 AM CDT | Special Weather Statement | DVN | 40 min |
| Apr 5, 1:54 AM CDT | Severe Thunderstorm Warning | DVN | 36 min |
| Apr 5, 3:23 AM CDT | Severe Thunderstorm Warning | DVN | 37 min |
| Apr 5, 3:57 AM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Apr 12, 2:48 AM CDT | Red Flag Warning | DVN | 17 hr |
| Apr 12, 2:27 PM CDT | Red Flag Warning | DVN | 30 hr |
| Apr 15, 3:17 PM CDT | Wind Advisory | DVN | 48 hr |
| Apr 15, 7:14 PM CDT | Special Weather Statement | DVN | 46 min |
| Apr 17, 12:50 PM CDT | River Flood Warning | DVN | 34 days |
| Apr 17, 1:05 PM CDT | River Flood Warning | DVN | 34 days |
| Apr 17, 1:07 PM CDT | River Flood Warning | DVN | 36 days |
| Apr 17, 3:00 PM CDT | Freeze Warning | DVN | 17 hr |
| Apr 20, 8:24 AM CDT | Special Weather Statement | DVN | 36 min |
| Apr 20, 1:50 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Apr 20, 2:06 PM CDT | Tornado Watch | SPC | 6 hr |
| Apr 21, 3:01 AM CDT | Freeze Watch | DVN | 48 hr |
| Apr 22, 3:03 PM CDT | Freeze Warning | DVN | 17 hr |
| Apr 23, 2:50 AM CDT | Freeze Warning | DVN | 29 hr |
| Apr 25, 1:32 PM CDT | Frost Advisory | DVN | 18 hr |
| Apr 30, 2:33 AM CDT | Wind Advisory | DVN | 17 hr |
| May 1, 8:52 AM CDT | Wind Advisory | DVN | 10 hr |
| May 6, 8:12 PM CDT | Mesoscale Discussion | SPC | 93 min |
| May 6, 8:50 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 6, 10:52 PM CDT | Severe Thunderstorm Warning | DVN | 38 min |
| May 6, 11:34 PM CDT | Mesoscale Discussion | SPC | 86 min |
| May 7, 12:19 AM CDT | Severe Thunderstorm Warning | DVN | 41 min |
| May 7, 12:47 AM CDT | Severe Thunderstorm Warning | DVN | 28 min |
| May 7, 2:10 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 7, 4:10 PM CDT | Severe Thunderstorm Watch | SPC | 10 hr |
| May 7, 5:19 PM CDT | Severe Thunderstorm Warning | DVN | 41 min |
| May 7, 5:35 PM CDT | Mesoscale Discussion | SPC | 85 min |
| May 7, 5:49 PM CDT | Severe Thunderstorm Warning | DVN | 56 min |
| May 7, 6:25 PM CDT | Severe Thunderstorm Warning | DVN | 35 min |
| May 7, 6:36 PM CDT | Severe Thunderstorm Warning | DVN | 39 min |
| May 7, 6:52 PM CDT | Severe Thunderstorm Warning | DVN | 38 min |
| May 13, 12:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| May 13, 12:54 PM CDT | Tornado Watch | SPC | 7 hr |
| May 13, 4:34 PM CDT | Flash Flood Warning | DVN | 4 hr |
| Jun 4, 1:38 PM CDT | Special Weather Statement | DVN | 37 min |
| Jun 4, 2:04 PM CDT | Special Weather Statement | DVN | 26 min |
| Jun 4, 2:31 PM CDT | Special Weather Statement | DVN | 44 min |
| Jun 4, 2:35 PM CDT | Severe Thunderstorm Warning | DVN | 40 min |
| Jun 18, 11:32 AM CDT | Special Weather Statement | DVN | 58 min |
| Jun 24, 5:45 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Jun 24, 6:28 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 24, 8:52 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 29, 5:49 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 29, 10:10 AM CDT | Severe Thunderstorm Warning | DVN | 50 min |
| Jun 29, 10:57 AM CDT | Severe Thunderstorm Warning | DVN | 33 min |
| Jun 29, 11:12 AM CDT | Severe Thunderstorm Warning | DVN | 48 min |
| Jun 30, 3:45 AM CDT | Dense Fog Advisory | DVN | 4 hr |
| Jun 30, 7:24 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Jul 12, 5:15 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 12, 8:43 AM CDT | Severe Thunderstorm Warning | DVN | 47 min |
| Jul 12, 10:05 AM CDT | Special Weather Statement | DVN | 40 min |
| Jul 14, 2:38 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 14, 3:52 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 25, 1:54 PM CDT | Heat Advisory | DVN | 3 days |
| Jul 27, 3:59 AM CDT | Excessive Heat Warning | DVN | 41 hr |
| Jul 28, 7:21 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 28, 7:30 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 28, 8:45 PM CDT | Severe Thunderstorm Warning | DVN | 60 min |
| Jul 28, 11:01 PM CDT | Special Weather Statement | DVN | 44 min |
| Aug 2, 9:41 PM CDT | Dense Fog Advisory | DVN | 11 hr |
| Aug 4, 2:50 AM CDT | Dense Fog Advisory | DVN | 6 hr |
| Aug 6, 2:42 AM CDT | Flood Watch | DVN | 21 hr |
| Aug 9, 11:23 PM CDT | Dense Fog Advisory | DVN | 10 hr |
| Aug 17, 5:13 AM CDT | Special Weather Statement | DVN | 32 min |
| Aug 17, 5:39 AM CDT | Special Weather Statement | DVN | 36 min |
| Aug 17, 5:49 AM CDT | Severe Thunderstorm Warning | DVN | 41 min |
| Aug 18, 2:58 AM CDT | Excessive Heat Watch | DVN | 72 hr |
| Aug 19, 3:01 AM CDT | Excessive Heat Warning | DVN | 7 days |
| Aug 21, 2:46 AM CDT | Excessive Heat Watch | DVN | 24 hr |
| Sep 12, 2:05 AM CDT | Dense Fog Advisory | DVN | 6 hr |
| Sep 28, 3:59 AM CDT | Dense Fog Advisory | DVN | 6 hr |
| Oct 9, 1:52 PM CDT | Frost Advisory | DVN | 19 hr |
| Oct 13, 5:19 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Oct 29, 2:38 AM CDT | Freeze Warning | DVN | 31 hr |
| Nov 25, 3:21 AM CST | Winter Weather Advisory | DVN | 33 hr |
| Nov 30, 2:37 AM CST | Winter Weather Advisory | DVN | 28 hr |
| Dec 3, 2:30 AM CST | Dense Fog Advisory | DVN | 7 hr |
| Dec 17, 1:35 PM CST | Wind Advisory | DVN | 19 hr |
| Dec 22, 6:23 PM CST | Dense Fog Advisory | DVN | 18 hr |
| Dec 23, 4:15 PM CST | Dense Fog Advisory | DVN | 20 hr |
| Dec 27, 8:48 AM CST | Winter Weather Advisory | DVN | 4 hr |
| Dec 28, 5:59 AM CST | Winter Weather Advisory | DVN | 18 hr |
| Dec 30, 5:56 PM CST | Winter Weather Advisory | DVN | 18 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 | 21 |
| Tornado Warning | 2 |
| Severe Thunderstorm Watch | 9 |
| Tornado Watch | 4 |
| Mesoscale Discussion | 21 |
| Special Weather Statement | 13 |
| Flooding | |
| Flash Flood Warning | 1 |
| River Flood Warning | 4 |
| Flood Watch | 1 |
| River Flood Watch | 1 |
| Winter | |
| Winter Storm Warning | 1 |
| Winter Storm Watch | 1 |
| Winter Weather Advisory | 10 |
| Heat | |
| Excessive Heat Warning | 2 |
| Excessive Heat Watch | 2 |
| Heat Advisory | 1 |
| Cold | |
| Freeze Warning | 4 |
| Freeze Watch | 1 |
| Frost Advisory | 2 |
| Wind and dust | |
| Wind Advisory | 6 |
| Fire | |
| Red Flag Warning | 2 |
| Fog and smoke | |
| Dense Fog Advisory | 13 |
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.