Alert archive / Iowa / Clay County
Weather alerts in Clay County, Iowa, 2023
98 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Clay County and its neighbors
Each county as a circle sized by its count in 2023. Tap one for its archive.
- Alerts
- 98
- Warnings
- 28
- Watches
- 20
- Advisories
- 33
- Busiest month
- July20 alerts
- Busiest day
- July 26, 20236 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Clay County, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 11 | 8 | 27% | 3 | 33% | 2 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Sioux Falls, SD: tornado warnings | 23 | 6 | 74% | 16 | 50% | 13 min |
| NWS Sioux Falls, SD: severe thunderstorm warnings | 228 | 126 | 45% | 282 | 82% | 18 min |
| NWS Sioux Falls, SD: flash flood warnings | 9 | 3 | 67% | 12 | 75% | 47 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, 2:10 PM CST | Ice Storm Warning | FSD | 44 hr |
| Jan 3, 3:04 AM CST | Winter Weather Advisory | FSD | 45 hr |
| Jan 6, 10:05 PM CST | Dense Fog Advisory | FSD | 14 hr |
| Jan 8, 11:54 PM CST | Dense Fog Advisory | FSD | 10 hr |
| Jan 11, 3:18 AM CST | Dense Fog Advisory | FSD | 11 hr |
| Jan 16, 3:03 PM CST | Winter Storm Watch | FSD | 24 hr |
| Jan 17, 3:11 PM CST | Winter Storm Warning | FSD | 42 hr |
| Jan 21, 5:56 PM CST | Dense Fog Advisory | FSD | 18 hr |
| Jan 22, 5:54 PM CST | Dense Fog Advisory | FSD | 12 hr |
| Jan 27, 3:12 AM CST | Winter Storm Warning | FSD | 39 hr |
| Jan 27, 3:12 AM CST | Winter Weather Advisory | FSD | 39 hr |
| Jan 28, 1:41 PM CST | Wind Chill Advisory | FSD | 20 hr |
| Jan 29, 1:48 PM CST | Wind Chill Advisory | FSD | 22 hr |
| Jan 30, 2:28 PM CST | Wind Chill Advisory | FSD | 20 hr |
| Feb 2, 3:35 AM CST | Wind Chill Advisory | FSD | 29 hr |
| Feb 19, 2:50 PM CST | Winter Storm Watch | FSD | 36 hr |
| Feb 21, 2:52 AM CST | Winter Storm Warning | FSD | 57 hr |
| Feb 23, 2:25 PM CST | Wind Chill Advisory | FSD | 20 hr |
| Mar 7, 3:20 AM CST | Winter Storm Watch | FSD | 28 hr |
| Mar 8, 3:30 AM CST | Winter Weather Advisory | FSD | 45 hr |
| Mar 15, 3:29 AM CDT | Winter Storm Watch | FSD | 12 hr |
| Mar 15, 3:26 PM CDT | Winter Weather Advisory | FSD | 40 hr |
| Mar 16, 7:06 PM CDT | Wind Advisory | FSD | 6 hr |
| Mar 22, 1:04 AM CDT | Dense Fog Advisory | FSD | 4 hr |
| Mar 23, 12:49 AM CDT | Winter Weather Advisory | FSD | 5 hr |
| Mar 30, 3:01 PM CDT | Winter Weather Advisory | FSD | 38 hr |
| Apr 3, 8:35 PM CDT | River Flood Warning | FSD | 70 hr |
| Apr 7, 12:30 PM CDT | Red Flag Warning | FSD | 8 hr |
| Apr 7, 2:50 PM CDT | Fire Weather Watch | FSD | 13 hr |
| Apr 8, 3:46 AM CDT | Red Flag Warning | FSD | 16 hr |
| Apr 10, 3:30 AM CDT | Fire Weather Watch | FSD | 10 hr |
| Apr 10, 1:44 PM CDT | Red Flag Warning | FSD | 31 hr |
| Apr 11, 4:19 PM CDT | Red Flag Warning | FSD | 28 hr |
| Apr 12, 3:05 AM CDT | Fire Weather Watch | FSD | 12 hr |
| Apr 12, 3:16 PM CDT | Red Flag Warning | FSD | 29 hr |
| Apr 15, 2:27 PM CDT | Wind Advisory | FSD | 29 hr |
| Apr 19, 2:45 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 19, 3:47 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Apr 30, 3:25 AM CDT | Wind Advisory | FSD | 17 hr |
| May 1, 2:59 PM CDT | Fire Weather Watch | FSD | 13 hr |
| May 2, 3:37 AM CDT | Red Flag Warning | FSD | 16 hr |
| May 7, 12:15 AM CDT | Dense Fog Advisory | FSD | 6 hr |
| May 8, 3:51 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 12, 1:22 PM CDT | Flood Watch | FSD | 48 hr |
| May 13, 12:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| May 13, 12:54 PM CDT | Tornado Watch | SPC | 7 hr |
| May 14, 8:50 AM CDT | River Flood Warning | FSD | 21 days |
| May 14, 8:50 AM CDT | River Flood Warning | FSD | 5 days |
| Jun 17, 2:24 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 17, 3:13 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 17, 4:48 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Jun 24, 3:10 AM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Jun 24, 5:31 AM CDT | Severe Thunderstorm Warning | FSD | 44 min |
| Jun 24, 9:37 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 24, 10:14 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 3, 3:48 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Jul 10, 2:09 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 10, 3:12 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 10, 5:43 PM CDT | Severe Thunderstorm Warning | FSD | 32 min |
| Jul 10, 5:59 PM CDT | Mesoscale Discussion | SPC | 61 min |
| Jul 10, 6:12 PM CDT | Severe Thunderstorm Warning | FSD | 33 min |
| Jul 12, 12:10 AM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 13, 1:28 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 13, 5:22 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 13, 7:17 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jul 13, 8:35 PM CDT | Severe Thunderstorm Warning | FSD | 40 min |
| Jul 26, 12:50 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Jul 26, 3:37 AM CDT | Severe Thunderstorm Warning | FSD | 38 min |
| Jul 26, 4:06 AM CDT | Severe Thunderstorm Warning | FSD | 39 min |
| Jul 26, 4:14 AM CDT | Heat Advisory | FSD | 16 hr |
| Jul 26, 4:26 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 26, 2:50 PM CDT | Heat Advisory | FSD | 29 hr |
| Jul 27, 8:55 AM CDT | Excessive Heat Warning | FSD | 11 hr |
| Jul 28, 2:46 AM CDT | Excessive Heat Warning | FSD | 17 hr |
| Jul 28, 3:55 PM CDT | Mesoscale Discussion | SPC | 95 min |
| Aug 3, 3:55 AM CDT | Dense Fog Advisory | FSD | 6 hr |
| Aug 11, 4:46 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 11, 7:40 PM CDT | Severe Thunderstorm Warning | FSD | 50 min |
| Aug 11, 8:15 PM CDT | Severe Thunderstorm Warning | FSD | 34 min |
| Aug 11, 9:08 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Aug 18, 2:40 PM CDT | Heat Advisory | FSD | 30 hr |
| Aug 19, 2:45 PM CDT | Excessive Heat Watch | FSD | 24 hr |
| Aug 20, 2:41 PM CDT | Excessive Heat Warning | FSD | 4 days |
| Sep 23, 6:23 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 28, 4:20 AM CDT | Dense Fog Advisory | FSD | 6 hr |
| Oct 6, 2:48 AM CDT | Frost Advisory | FSD | 30 hr |
| Oct 6, 2:48 AM CDT | Freeze Warning | FSD | 30 hr |
| Oct 9, 3:04 PM CDT | Frost Advisory | FSD | 18 hr |
| Oct 23, 9:27 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 24, 12:05 AM CDT | Severe Thunderstorm Warning | FSD | 10 min |
| Oct 24, 12:14 AM CDT | Severe Thunderstorm Warning | FSD | 16 min |
| Oct 24, 12:30 AM CDT | Severe Thunderstorm Warning | FSD | 15 min |
| Oct 27, 2:54 PM CDT | Winter Weather Advisory | FSD | 34 hr |
| Oct 30, 2:37 PM CDT | Wind Advisory | FSD | 19 hr |
| Nov 8, 2:55 PM CST | Fire Weather Watch | FSD | 24 hr |
| Nov 15, 2:45 PM CST | Wind Advisory | FSD | 23 hr |
| Dec 3, 7:06 PM CST | Dense Fog Advisory | FSD | 16 hr |
| Dec 22, 3:30 PM CST | Dense Fog Advisory | FSD | 22 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 | 11 |
| Severe Thunderstorm Watch | 8 |
| Tornado Watch | 1 |
| Mesoscale Discussion | 17 |
| Flooding | |
| River Flood Warning | 3 |
| Flood Watch | 1 |
| Winter | |
| Ice Storm Warning | 1 |
| Winter Storm Warning | 3 |
| Winter Storm Watch | 4 |
| Winter Weather Advisory | 7 |
| Heat | |
| Excessive Heat Warning | 3 |
| Excessive Heat Watch | 1 |
| Heat Advisory | 3 |
| Cold | |
| Freeze Warning | 1 |
| Frost Advisory | 2 |
| Wind Chill Advisory | 5 |
| Wind and dust | |
| Wind Advisory | 5 |
| Fire | |
| Red Flag Warning | 6 |
| Fire Weather Watch | 5 |
| Fog and smoke | |
| Dense Fog Advisory | 11 |
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.