Alert archive / Iowa / Sioux County
Weather alerts in Sioux County, Iowa, 2025
188 weather alerts in 2025, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Sioux County and its neighbors
Each county as a circle sized by its count in 2025. Tap one for its archive.
- Alerts
- 188
- Warnings
- 74
- Watches
- 29
- Advisories
- 48
- Busiest month
- July50 alerts
- Busiest day
- July 28, 202511 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 1 tornado warnings covering Sioux County in 2025 had a tornado report inside them.
Sioux County, 2025
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 1 | 0% | 0 | ||
| Severe thunderstorm warnings | 41 | 29 | 29% | 24 | 96% | 17 min |
| Flash flood warnings | 8 | 2 | 75% | 3 | 67% | 174 min |
Each office's whole area, 2025
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Sioux Falls, SD: tornado warnings | 20 | 5 | 75% | 9 | 56% | 8 min |
| NWS Sioux Falls, SD: severe thunderstorm warnings | 332 | 191 | 42% | 500 | 85% | 22 min |
| NWS Sioux Falls, SD: flash flood warnings | 25 | 9 | 64% | 19 | 74% | 80 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 17, 11:30 AM CST | Wind Advisory | FSD | 7 hr |
| Jan 17, 1:13 PM CST | Cold Weather Advisory | FSD | 47 hr |
| Jan 18, 1:24 PM CST | Cold Weather Advisory | FSD | 71 hr |
| Jan 20, 2:45 AM CST | Extreme Cold Warning | FSD | 33 hr |
| Jan 28, 1:33 PM CST | Red Flag Warning | FSD | 4 hr |
| Feb 1, 2:44 AM CST | Wind Advisory | FSD | 12 hr |
| Feb 2, 2:07 AM CST | Dense Fog Advisory | FSD | 9 hr |
| Feb 10, 2:13 AM CST | Winter Weather Advisory | FSD | 22 hr |
| Feb 10, 2:26 PM CST | Cold Weather Advisory | FSD | 19 hr |
| Feb 12, 2:49 AM CST | Cold Weather Advisory | FSD | 30 hr |
| Feb 16, 3:02 AM CST | Cold Weather Advisory | FSD | 42 hr |
| Feb 16, 3:02 AM CST | Extreme Cold Watch | FSD | 24 hr |
| Feb 17, 2:57 AM CST | Extreme Cold Warning | FSD | 33 hr |
| Feb 18, 3:09 AM CST | Cold Weather Advisory | FSD | 31 hr |
| Feb 19, 2:40 AM CST | Cold Weather Advisory | FSD | 30 hr |
| Feb 27, 1:35 PM CST | Wind Advisory | FSD | 28 hr |
| Feb 28, 3:20 AM CST | Red Flag Warning | FSD | 15 hr |
| Mar 3, 3:51 AM CST | Winter Storm Watch | FSD | 24 hr |
| Mar 3, 2:10 PM CST | Winter Weather Advisory | FSD | 40 hr |
| Mar 4, 10:49 AM CST | Blizzard Warning | FSD | 31 hr |
| Mar 4, 11:22 AM CST | High Wind Warning | FSD | 19 hr |
| Mar 6, 3:20 AM CST | Winter Weather Advisory | FSD | 33 hr |
| Mar 14, 1:46 PM CDT | Wind Advisory | FSD | 25 hr |
| Mar 14, 1:55 PM CDT | Winter Weather Advisory | FSD | 23 hr |
| Mar 14, 5:01 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Mar 14, 5:43 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Mar 14, 6:45 PM CDT | Severe Thunderstorm Warning | FSD | 45 min |
| Mar 17, 3:13 AM CDT | Winter Storm Watch | FSD | 24 hr |
| Mar 17, 3:23 AM CDT | Red Flag Warning | FSD | 16 hr |
| Mar 17, 2:50 PM CDT | High Wind Watch | FSD | 13 hr |
| Mar 18, 3:21 AM CDT | Blizzard Warning | FSD | 40 hr |
| Mar 18, 3:21 AM CDT | High Wind Warning | FSD | 40 hr |
| Mar 18, 3:21 AM CDT | Winter Weather Advisory | FSD | 34 hr |
| Mar 19, 5:54 AM CDT | Mesoscale Discussion | SPC | 5 hr |
| Mar 22, 2:25 PM CDT | Wind Advisory | FSD | 29 hr |
| Mar 27, 2:06 PM CDT | Fire Weather Watch | FSD | 14 hr |
| Mar 28, 3:43 AM CDT | Red Flag Warning | FSD | 16 hr |
| Mar 28, 7:25 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 9, 2:23 AM CDT | Red Flag Warning | FSD | 18 hr |
| Apr 14, 3:10 AM CDT | Wind Advisory | FSD | 16 hr |
| Apr 14, 1:28 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 17, 12:46 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 17, 8:06 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Apr 18, 1:16 AM CDT | Severe Thunderstorm Warning | FSD | 44 min |
| Apr 18, 2:10 AM CDT | Severe Thunderstorm Warning | FSD | 35 min |
| Apr 28, 10:41 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 28, 12:29 PM CDT | Tornado Watch | SPC | 10 hr |
| Apr 28, 5:29 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Apr 28, 5:59 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Apr 28, 6:06 PM CDT | Severe Thunderstorm Warning | FSD | 39 min |
| Apr 28, 6:41 PM CDT | Severe Thunderstorm Warning | FSD | 49 min |
| May 8, 2:35 PM CDT | Fire Weather Watch | FSD | 48 hr |
| May 10, 2:05 PM CDT | Fire Weather Watch | FSD | 32 hr |
| May 10, 2:05 PM CDT | Red Flag Warning | FSD | 32 hr |
| May 11, 9:50 PM CDT | Red Flag Warning | FSD | 23 hr |
| May 12, 1:42 PM CDT | Fire Weather Watch | FSD | 14 hr |
| May 13, 3:33 AM CDT | Red Flag Warning | FSD | 17 hr |
| May 14, 2:00 PM CDT | Wind Advisory | FSD | 53 hr |
| May 15, 1:08 AM CDT | Mesoscale Discussion | SPC | 97 min |
| May 15, 1:36 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 15, 4:04 AM CDT | Mesoscale Discussion | SPC | 86 min |
| May 15, 7:23 AM CDT | Mesoscale Discussion | SPC | 97 min |
| May 15, 2:15 PM CDT | Wind Advisory | FSD | 29 hr |
| May 19, 8:25 PM CDT | High Wind Warning | FSD | 4 hr |
| Jun 2, 1:20 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Jun 2, 3:47 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Jun 2, 4:07 PM CDT | Severe Thunderstorm Warning | FSD | 38 min |
| Jun 2, 4:49 PM CDT | Severe Thunderstorm Warning | FSD | 26 min |
| Jun 2, 4:50 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 2, 5:12 PM CDT | Severe Thunderstorm Warning | FSD | 48 min |
| Jun 2, 5:41 PM CDT | Severe Thunderstorm Warning | FSD | 49 min |
| Jun 2, 6:23 PM CDT | Severe Thunderstorm Warning | FSD | 52 min |
| Jun 2, 8:06 PM CDT | Severe Thunderstorm Warning | FSD | 24 min |
| Jun 2, 8:22 PM CDT | Severe Thunderstorm Warning | FSD | 23 min |
| Jun 2, 9:38 PM CDT | River Flood Warning | FSD | 9 hr |
| Jun 11, 1:56 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jun 11, 2:50 PM CDT | Severe Thunderstorm Warning | FSD | 40 min |
| Jun 11, 2:53 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 14, 4:37 AM CDT | Dense Fog Advisory | FSD | 4 hr |
| Jun 14, 6:30 PM CDT | Severe Thunderstorm Warning | FSD | 45 min |
| Jun 14, 6:32 PM CDT | Severe Thunderstorm Warning | FSD | 43 min |
| Jun 14, 6:47 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Jun 14, 7:08 PM CDT | Severe Thunderstorm Warning | FSD | 52 min |
| Jun 14, 7:13 PM CDT | Severe Thunderstorm Warning | FSD | 23 min |
| Jun 15, 8:24 AM CDT | Severe Thunderstorm Warning | FSD | 51 min |
| Jun 17, 2:48 PM CDT | Flash Flood Warning | FSD | 3 hr |
| Jun 17, 3:34 PM CDT | Flash Flood Warning | FSD | 3 hr |
| Jun 18, 2:02 PM CDT | Extreme Heat Watch | FSD | 23 hr |
| Jun 19, 1:30 PM CDT | Extreme Heat Warning | FSD | 3 days |
| Jun 25, 2:16 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Jun 27, 10:29 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jun 27, 11:47 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jun 28, 11:12 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 29, 1:01 AM CDT | Mesoscale Discussion | SPC | 119 min |
| Jun 29, 3:38 AM CDT | Severe Thunderstorm Warning | FSD | 37 min |
| Jun 29, 4:06 AM CDT | Severe Thunderstorm Warning | FSD | 39 min |
| Jul 2, 11:52 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Jul 7, 3:14 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 7, 5:52 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Jul 10, 1:39 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 13, 5:47 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Jul 15, 8:19 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Jul 15, 8:29 PM CDT | Severe Thunderstorm Warning | FSD | 61 min |
| Jul 15, 8:41 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 18, 8:06 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 18, 11:30 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Jul 20, 2:19 PM CDT | Heat Advisory | FSD | 30 hr |
| Jul 22, 3:23 AM CDT | Heat Advisory | FSD | 17 hr |
| Jul 22, 2:13 PM CDT | Heat Advisory | FSD | 30 hr |
| Jul 24, 12:48 AM CDT | Flash Flood Warning | FSD | 3 hr |
| Jul 26, 2:53 AM CDT | Extreme Heat Watch | FSD | 11 hr |
| Jul 26, 4:32 AM CDT | Dense Fog Advisory | FSD | 4 hr |
| Jul 26, 2:08 PM CDT | Extreme Heat Warning | FSD | 30 hr |
| Jul 27, 2:34 PM CDT | Extreme Heat Warning | FSD | 29 hr |
| Jul 27, 4:47 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jul 27, 9:47 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Jul 27, 11:28 PM CDT | Severe Thunderstorm Warning | FSD | 47 min |
| Jul 27, 11:58 PM CDT | Severe Thunderstorm Warning | FSD | 62 min |
| Jul 28, 12:14 AM CDT | Severe Thunderstorm Warning | FSD | 46 min |
| Jul 28, 12:30 AM CDT | Severe Thunderstorm Warning | FSD | 45 min |
| Jul 28, 1:00 AM CDT | Severe Thunderstorm Warning | FSD | 15 min |
| Jul 28, 1:15 AM CDT | Severe Thunderstorm Warning | FSD | 45 min |
| Jul 28, 1:44 AM CDT | Flash Flood Warning | FSD | 91 min |
| Jul 28, 1:57 AM CDT | Severe Thunderstorm Warning | FSD | 48 min |
| Jul 28, 5:49 PM CDT | Mesoscale Discussion | SPC | 116 min |
| Jul 28, 6:57 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 28, 8:13 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 28, 8:46 PM CDT | Severe Thunderstorm Warning | FSD | 44 min |
| Jul 28, 8:52 PM CDT | Severe Thunderstorm Warning | FSD | 38 min |
| Jul 28, 9:23 PM CDT | Severe Thunderstorm Warning | FSD | 37 min |
| Jul 28, 9:34 PM CDT | Tornado Warning | FSD | 26 min |
| Jul 28, 9:39 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 28, 9:55 PM CDT | Severe Thunderstorm Warning | FSD | 80 min |
| Jul 29, 8:27 AM CDT | Severe Thunderstorm Warning | FSD | 19 min |
| Jul 29, 2:29 PM CDT | Flood Watch | FSD | 11 hr |
| Jul 29, 4:34 PM CDT | Mesoscale Discussion | SPC | 56 min |
| Jul 29, 7:30 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Jul 29, 7:56 PM CDT | Severe Thunderstorm Warning | FSD | 64 min |
| Jul 29, 8:24 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 29, 8:48 PM CDT | Severe Thunderstorm Warning | FSD | 42 min |
| Jul 29, 8:56 PM CDT | Severe Thunderstorm Warning | FSD | 49 min |
| Jul 29, 9:26 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Jul 29, 9:28 PM CDT | Severe Thunderstorm Warning | FSD | 62 min |
| Jul 29, 9:45 PM CDT | Severe Thunderstorm Warning | FSD | 46 min |
| Jul 29, 10:19 PM CDT | Flash Flood Warning | FSD | 4 hr |
| Jul 30, 7:55 PM CDT | River Flood Warning | FSD | 30 hr |
| Aug 5, 11:33 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Aug 7, 2:15 PM CDT | Heat Advisory | FSD | 30 hr |
| Aug 8, 9:34 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 15, 1:59 PM CDT | Heat Advisory | FSD | 30 hr |
| Aug 18, 1:50 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Aug 18, 3:36 AM CDT | Flash Flood Warning | FSD | 2 hr |
| Aug 30, 4:01 PM CDT | Flash Flood Warning | FSD | 119 min |
| Sep 4, 4:56 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Sep 6, 4:17 PM CDT | Frost Advisory | FSD | 17 hr |
| Sep 9, 10:49 PM CDT | Dense Fog Advisory | FSD | 12 hr |
| Sep 14, 3:28 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Sep 16, 2:21 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Sep 16, 9:09 PM CDT | Flash Flood Warning | FSD | 63 min |
| Sep 21, 7:35 PM CDT | Severe Thunderstorm Warning | FSD | 40 min |
| Sep 21, 8:20 PM CDT | Severe Thunderstorm Warning | FSD | 40 min |
| Sep 21, 8:55 PM CDT | Severe Thunderstorm Warning | FSD | 50 min |
| Oct 15, 7:31 PM CDT | Dense Fog Advisory | FSD | 8 hr |
| Oct 20, 2:36 PM CDT | Wind Advisory | FSD | 27 hr |
| Oct 28, 10:51 AM CDT | Wind Advisory | FSD | 16 hr |
| Oct 30, 1:31 AM CDT | Dense Fog Advisory | FSD | 9 hr |
| Nov 7, 9:12 PM CST | Winter Weather Advisory | FSD | 17 hr |
| Nov 20, 4:13 AM CST | Dense Fog Advisory | FSD | 8 hr |
| Nov 24, 1:42 PM CST | Wind Advisory | FSD | 37 hr |
| Nov 25, 4:34 AM CST | Dense Fog Advisory | FSD | 4 hr |
| Nov 26, 2:26 PM CST | Winter Storm Watch | FSD | 24 hr |
| Nov 27, 2:53 PM CST | Winter Storm Warning | FSD | 57 hr |
| Dec 5, 3:33 AM CST | Winter Weather Advisory | FSD | 44 hr |
| Dec 6, 3:08 AM CST | Winter Storm Warning | FSD | 21 hr |
| Dec 6, 12:25 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Dec 8, 5:35 AM CST | Dense Fog Advisory | FSD | 15 hr |
| Dec 8, 2:45 PM CST | High Wind Warning | FSD | 39 hr |
| Dec 8, 2:45 PM CST | Winter Storm Watch | FSD | 21 hr |
| Dec 10, 3:13 AM CST | Winter Weather Advisory | FSD | 39 hr |
| Dec 12, 2:24 AM CST | Winter Weather Advisory | FSD | 34 hr |
| Dec 12, 2:08 PM CST | Cold Weather Advisory | FSD | 44 hr |
| Dec 16, 1:57 PM CST | High Wind Watch | FSD | 13 hr |
| Dec 17, 2:43 AM CST | High Wind Warning | FSD | 42 hr |
| Dec 18, 6:47 AM CST | Winter Weather Advisory | FSD | 11 hr |
| Dec 24, 1:19 PM CST | Dense Fog Advisory | FSD | 68 hr |
| Dec 27, 12:47 PM CST | Dense Fog Advisory | FSD | 17 hr |
| Dec 27, 2:10 PM CST | Wind Advisory | FSD | 34 hr |
| Dec 27, 2:11 PM CST | Winter Weather Advisory | FSD | 40 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 archive20242026
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.