Alert archive / Iowa / Clayton County
Weather alerts in Clayton County, Iowa, 2018
141 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Clayton County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 141
- Warnings
- 34
- Watches
- 20
- Advisories
- 37
- Busiest month
- June20 alerts
- Busiest day
- October 9, 20187 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Clayton County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 6 | 3 | 50% | 4 | 50% | 4 min |
| Flash flood warnings | 3 | 1 | 67% | 1 | 0% |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS La Crosse, WI: tornado warnings | 11 | 0 | 100% | 4 | 0% | |
| NWS La Crosse, WI: severe thunderstorm warnings | 115 | 62 | 46% | 187 | 67% | 24 min |
| NWS La Crosse, WI: flash flood warnings | 28 | 18 | 36% | 53 | 81% | 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, 12:11 PM CST | Wind Chill Advisory | ARX | 23 hr |
| Jan 3, 2:07 PM CST | Wind Chill Advisory | ARX | 17 hr |
| Jan 10, 3:05 AM CST | Dense Fog Advisory | ARX | 8 hr |
| Jan 10, 2:07 PM CST | Winter Weather Advisory | ARX | 28 hr |
| Jan 10, 3:21 PM CST | Dense Fog Advisory | ARX | 11 hr |
| Jan 12, 3:00 PM CST | Wind Chill Advisory | ARX | 18 hr |
| Jan 14, 3:51 AM CST | Wind Chill Advisory | ARX | 54 hr |
| Jan 14, 3:51 AM CST | Winter Weather Advisory | ARX | 44 hr |
| Jan 22, 1:45 PM CST | River Flood Warning | ARX | 71 hr |
| Feb 4, 2:46 PM CST | Winter Weather Advisory | ARX | 28 hr |
| Feb 7, 2:51 PM CST | Winter Weather Advisory | ARX | 39 hr |
| Feb 8, 11:19 AM CST | Winter Storm Warning | ARX | 19 hr |
| Feb 8, 9:07 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Feb 18, 3:48 AM CST | Winter Storm Watch | ARX | 22 hr |
| Feb 19, 1:32 AM CST | Winter Weather Advisory | ARX | 36 hr |
| Feb 19, 5:22 PM CST | Dense Fog Advisory | ARX | 11 hr |
| Feb 22, 3:04 AM CST | Winter Weather Advisory | ARX | 30 hr |
| Mar 4, 3:15 PM CST | Winter Weather Advisory | ARX | 42 hr |
| Mar 5, 1:17 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Mar 22, 3:23 AM CDT | Winter Storm Watch | ARX | 24 hr |
| Mar 23, 3:50 AM CDT | Winter Storm Warning | ARX | 36 hr |
| Mar 24, 3:58 AM CDT | Winter Weather Advisory | ARX | 12 hr |
| Mar 30, 2:42 PM CDT | Wind Advisory | ARX | 22 hr |
| Apr 2, 11:09 AM CDT | Winter Weather Advisory | ARX | 41 hr |
| Apr 13, 4:04 PM CDT | Winter Weather Advisory | ARX | 51 hr |
| Apr 13, 6:56 PM CDT | Special Weather Statement | ARX | 64 min |
| Apr 14, 2:56 AM CDT | Wind Advisory | ARX | 10 hr |
| Apr 16, 3:11 AM CDT | Winter Storm Watch | ARX | 36 hr |
| Apr 17, 3:35 AM CDT | Winter Storm Warning | ARX | 44 hr |
| Apr 27, 11:32 AM CDT | River Flood Warning | ARX | 17 days |
| Apr 29, 3:37 AM CDT | Red Flag Warning | ARX | 17 hr |
| Apr 29, 10:26 AM CDT | River Flood Warning | ARX | 14 days |
| May 1, 5:47 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 1, 7:21 PM CDT | Special Weather Statement | ARX | 54 min |
| May 1, 7:55 PM CDT | Mesoscale Discussion | SPC | 95 min |
| May 1, 8:38 PM CDT | Special Weather Statement | ARX | 37 min |
| May 1, 9:38 PM CDT | Mesoscale Discussion | SPC | 67 min |
| May 2, 5:31 PM CDT | Special Weather Statement | ARX | 74 min |
| May 3, 3:20 PM CDT | Flood Watch | ARX | 21 hr |
| May 3, 10:08 PM CDT | River Flood Warning | ARX | 4 days |
| May 3, 10:08 PM CDT | River Flood Warning | ARX | 4 days |
| May 9, 5:19 AM CDT | Areal Flood Advisory | ARX | 3 hr |
| May 25, 12:59 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 25, 2:02 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| May 25, 5:20 PM CDT | Mesoscale Discussion | SPC | 115 min |
| May 25, 6:29 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 25, 6:55 PM CDT | Severe Thunderstorm Warning | ARX | 50 min |
| May 25, 7:05 PM CDT | Severe Thunderstorm Warning | ARX | 40 min |
| May 25, 7:40 PM CDT | Severe Thunderstorm Warning | ARX | 65 min |
| May 25, 9:43 PM CDT | Special Weather Statement | ARX | 47 min |
| May 25, 11:01 PM CDT | Special Weather Statement | ARX | 44 min |
| Jun 2, 6:14 PM CDT | Special Weather Statement | ARX | 31 min |
| Jun 2, 6:53 PM CDT | Special Weather Statement | ARX | 22 min |
| Jun 9, 11:04 AM CDT | Flash Flood Watch | ARX | 14 hr |
| Jun 9, 2:26 PM CDT | Tornado Watch | SPC | 5 hr |
| Jun 9, 3:52 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 9, 6:30 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 9, 7:02 PM CDT | Severe Thunderstorm Warning | ARX | 88 min |
| Jun 9, 7:43 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 9, 8:57 PM CDT | River Flood Warning | ARX | 3 days |
| Jun 9, 8:57 PM CDT | River Flood Warning | ARX | 3 days |
| Jun 9, 9:30 PM CDT | Flash Flood Warning | ARX | 3 hr |
| Jun 15, 2:10 PM CDT | Heat Advisory | ARX | 53 hr |
| Jun 18, 5:40 PM CDT | Special Weather Statement | ARX | 50 min |
| Jun 18, 6:41 PM CDT | Special Weather Statement | ARX | 79 min |
| Jun 23, 9:16 PM CDT | River Flood Warning | ARX | 8 days |
| Jun 26, 9:26 PM CDT | River Flood Warning | ARX | 61 hr |
| Jun 28, 3:13 AM CDT | Excessive Heat Warning | ARX | 64 hr |
| Jun 28, 3:13 AM CDT | Heat Advisory | ARX | 64 hr |
| Jun 30, 1:39 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 30, 5:23 PM CDT | Special Weather Statement | ARX | 112 min |
| Jun 30, 8:05 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Jul 3, 3:08 PM CDT | Heat Advisory | ARX | 27 hr |
| Jul 4, 4:18 PM CDT | Special Weather Statement | ARX | 72 min |
| Jul 4, 5:21 PM CDT | Special Weather Statement | ARX | 24 min |
| Jul 11, 3:42 PM CDT | Heat Advisory | ARX | 28 hr |
| Jul 13, 3:54 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 13, 5:08 PM CDT | Special Weather Statement | ARX | 112 min |
| Jul 13, 5:18 PM CDT | Special Weather Statement | ARX | 57 min |
| Jul 13, 5:29 PM CDT | Severe Thunderstorm Warning | ARX | 61 min |
| Jul 13, 6:16 PM CDT | Areal Flood Advisory | ARX | 119 min |
| Jul 25, 4:05 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 25, 6:29 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Aug 1, 6:52 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 1, 9:49 PM CDT | Special Weather Statement | ARX | 56 min |
| Aug 5, 3:48 PM CDT | Special Weather Statement | ARX | 72 min |
| Aug 5, 10:08 PM CDT | Special Weather Statement | ARX | 52 min |
| Aug 5, 11:27 PM CDT | Special Weather Statement | ARX | 63 min |
| Aug 8, 1:03 AM CDT | Dense Fog Advisory | ARX | 8 hr |
| Aug 25, 4:04 AM CDT | Dense Fog Advisory | ARX | 5 hr |
| Aug 27, 11:33 AM CDT | Flash Flood Watch | ARX | 33 hr |
| Aug 28, 7:50 AM CDT | Mesoscale Discussion | SPC | 115 min |
| Aug 28, 10:08 AM CDT | Severe Thunderstorm Warning | ARX | 33 min |
| Aug 28, 12:14 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 28, 1:14 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 31, 3:07 PM CDT | Flash Flood Watch | ARX | 23 hr |
| Sep 1, 6:34 PM CDT | Mesoscale Discussion | SPC | 56 min |
| Sep 2, 2:24 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 2, 3:28 PM CDT | Special Weather Statement | ARX | 62 min |
| Sep 3, 5:23 AM CDT | River Flood Warning | ARX | 5 days |
| Sep 3, 5:47 PM CDT | Mesoscale Discussion | SPC | 58 min |
| Sep 3, 9:27 PM CDT | River Flood Warning | ARX | 4 days |
| Sep 3, 11:58 PM CDT | Flash Flood Warning | ARX | 6 hr |
| Sep 4, 4:00 AM CDT | Flash Flood Watch | ARX | 33 hr |
| Sep 4, 9:04 PM CDT | Special Weather Statement | ARX | 86 min |
| Sep 18, 8:17 AM CDT | Special Weather Statement | ARX | 28 min |
| Sep 19, 4:10 AM CDT | Flash Flood Watch | ARX | 32 hr |
| Sep 20, 1:16 AM CDT | Flash Flood Warning | ARX | 3 hr |
| Sep 20, 2:37 AM CDT | River Flood Warning | ARX | 5 days |
| Sep 20, 2:37 AM CDT | River Flood Warning | ARX | 4 days |
| Sep 20, 2:51 AM CDT | Areal Flood Warning | ARX | 12 hr |
| Sep 20, 8:20 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Sep 20, 9:12 PM CDT | Special Weather Statement | ARX | 93 min |
| Sep 25, 1:07 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Sep 28, 3:40 AM CDT | Frost Advisory | ARX | 28 hr |
| Oct 1, 11:27 AM CDT | Areal Flood Advisory | ARX | 7 hr |
| Oct 1, 12:58 PM CDT | River Flood Warning | ARX | 38 hr |
| Oct 1, 6:11 PM CDT | River Flood Warning | ARX | 43 hr |
| Oct 3, 5:13 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 3, 7:58 PM CDT | Special Weather Statement | ARX | 77 min |
| Oct 4, 1:58 PM CDT | Flash Flood Watch | ARX | 39 hr |
| Oct 8, 3:13 AM CDT | Flood Watch | ARX | 56 hr |
| Oct 8, 9:59 AM CDT | River Flood Warning | ARX | 5 days |
| Oct 9, 6:24 AM CDT | River Flood Warning | ARX | 4 days |
| Oct 9, 2:39 PM CDT | Special Weather Statement | ARX | 36 min |
| Oct 9, 3:20 PM CDT | Special Weather Statement | ARX | 25 min |
| Oct 9, 3:52 PM CDT | Special Weather Statement | ARX | 23 min |
| Oct 9, 5:08 PM CDT | Special Weather Statement | ARX | 82 min |
| Oct 9, 5:09 PM CDT | Tornado Watch | SPC | 4 hr |
| Oct 9, 6:37 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Oct 11, 2:39 AM CDT | Freeze Warning | ARX | 30 hr |
| Oct 12, 12:22 PM CDT | Frost Advisory | ARX | 21 hr |
| Oct 15, 8:21 PM CDT | River Flood Warning | ARX | 6 days |
| Oct 19, 7:30 PM CDT | Wind Advisory | ARX | 19 hr |
| Oct 27, 2:46 PM CDT | Wind Advisory | ARX | 22 hr |
| Nov 16, 2:45 AM CST | Winter Weather Advisory | ARX | 27 hr |
| Dec 11, 2:28 PM CST | Winter Weather Advisory | ARX | 22 hr |
| Dec 12, 8:48 PM CST | Dense Fog Advisory | ARX | 13 hr |
| Dec 28, 2:34 AM CST | Winter Weather Advisory | ARX | 9 hr |
| Dec 30, 2:48 PM CST | Winter Weather Advisory | ARX | 33 hr |
| Dec 31, 11:50 AM CST | Mesoscale Discussion | SPC | 6 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 | 6 |
| Severe Thunderstorm Watch | 7 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 22 |
| Special Weather Statement | 28 |
| Flooding | |
| Areal Flood Warning | 1 |
| Flash Flood Warning | 3 |
| River Flood Warning | 18 |
| Flash Flood Watch | 6 |
| Flood Watch | 2 |
| Areal Flood Advisory | 3 |
| Winter | |
| Winter Storm Warning | 3 |
| Winter Storm Watch | 3 |
| Winter Weather Advisory | 14 |
| Heat | |
| Excessive Heat Warning | 1 |
| Heat Advisory | 4 |
| Cold | |
| Freeze Warning | 1 |
| Frost Advisory | 2 |
| Wind Chill Advisory | 4 |
| Wind and dust | |
| Wind Advisory | 4 |
| Fire | |
| Red Flag Warning | 1 |
| Fog and smoke | |
| Dense Fog Advisory | 6 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20172019
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.