Alert archive / Iowa / Sac County
Weather alerts in Sac County, Iowa, 2023
84 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Sac County and its neighbors
Each county as a circle sized by its count in 2023. Tap one for its archive.
- Alerts
- 84
- Warnings
- 20
- Watches
- 17
- Advisories
- 26
- Busiest month
- April15 alerts
- Busiest day
- April 20, 20235 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
2 of 4 tornado warnings covering Sac County in 2023 had a tornado report inside them; 0 of 1 tornado reports fell inside a warning.
Sac County, 2023
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 4 | 2 | 50% | 1 | 0% | |
| Severe thunderstorm warnings | 8 | 6 | 25% | 7 | 100% | 12 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 Des Moines, IA: tornado warnings | 37 | 13 | 65% | 26 | 73% | 15 min |
| NWS Des Moines, IA: severe thunderstorm warnings | 195 | 120 | 38% | 328 | 88% | 22 min |
| NWS Des Moines, IA: flash flood warnings | 5 | 3 | 40% | 4 | 75% | 103 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, 3:23 PM CST | Ice Storm Warning | DMX | 43 hr |
| Jan 1, 3:23 PM CST | Winter Weather Advisory | DMX | 3 days |
| Jan 11, 8:16 AM CST | Dense Fog Advisory | DMX | 6 hr |
| Jan 17, 3:07 AM CST | Winter Storm Watch | DMX | 12 hr |
| Jan 17, 3:09 PM CST | Winter Storm Warning | DMX | 45 hr |
| Jan 22, 12:48 AM CST | Dense Fog Advisory | DMX | 11 hr |
| Jan 22, 6:46 PM CST | Dense Fog Advisory | DMX | 14 hr |
| Jan 27, 3:08 AM CST | Winter Storm Warning | DMX | 42 hr |
| Jan 27, 3:08 AM CST | Winter Weather Advisory | DMX | 45 hr |
| Jan 28, 2:06 PM CST | Wind Chill Advisory | DMX | 21 hr |
| Jan 29, 2:28 PM CST | Wind Chill Advisory | DMX | 20 hr |
| Jan 30, 1:34 PM CST | Wind Chill Advisory | DMX | 20 hr |
| Feb 2, 3:14 AM CST | Wind Chill Advisory | DMX | 30 hr |
| Feb 21, 2:47 AM CST | Winter Weather Advisory | DMX | 57 hr |
| Mar 7, 3:38 AM CST | Winter Storm Watch | DMX | 35 hr |
| Mar 8, 3:04 PM CST | Winter Weather Advisory | DMX | 33 hr |
| Mar 15, 3:28 PM CDT | Winter Weather Advisory | DMX | 28 hr |
| Mar 16, 3:12 AM CDT | Wind Advisory | DMX | 25 hr |
| Mar 31, 3:30 AM CDT | Wind Advisory | DMX | 28 hr |
| Apr 7, 3:03 PM CDT | Fire Weather Watch | DMX | 12 hr |
| Apr 8, 2:41 AM CDT | Red Flag Warning | DMX | 17 hr |
| Apr 11, 3:04 PM CDT | Fire Weather Watch | DMX | 12 hr |
| Apr 12, 2:57 AM CDT | Fire Weather Watch | DMX | 11 hr |
| Apr 12, 2:57 AM CDT | Red Flag Warning | DMX | 17 hr |
| Apr 12, 2:20 PM CDT | Red Flag Warning | DMX | 30 hr |
| Apr 15, 2:47 PM CDT | Wind Advisory | DMX | 44 hr |
| Apr 19, 2:45 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 19, 3:45 PM CDT | Tornado Watch | SPC | 7 hr |
| Apr 19, 7:12 PM CDT | Severe Thunderstorm Warning | DMX | 48 min |
| Apr 19, 7:56 PM CDT | Severe Thunderstorm Warning | DMX | 49 min |
| Apr 19, 8:03 PM CDT | Tornado Warning | DMX | 42 min |
| Apr 19, 8:17 PM CDT | Severe Thunderstorm Warning | DMX | 28 min |
| Apr 19, 8:21 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 30, 2:41 AM CDT | Wind Advisory | DMX | 17 hr |
| May 6, 1:42 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 6, 10:41 PM CDT | Dense Fog Advisory | DMX | 12 hr |
| May 7, 12:45 PM CDT | Severe Thunderstorm Warning | DMX | 45 min |
| May 8, 3:51 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 13, 12:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| May 13, 12:54 PM CDT | Tornado Watch | SPC | 7 hr |
| May 13, 3:31 PM CDT | Mesoscale Discussion | SPC | 119 min |
| May 13, 4:31 PM CDT | Tornado Warning | DMX | 29 min |
| May 13, 4:57 PM CDT | Tornado Warning | DMX | 16 min |
| 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, 6:35 AM CDT | Special Weather Statement | DMX | 40 min |
| Jun 24, 1:27 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 24, 9:37 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 24, 10:14 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 4, 6:55 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 10, 2:09 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 10, 3:12 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 12, 4:41 AM CDT | Mesoscale Discussion | SPC | 94 min |
| Jul 12, 5:15 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 12, 6:07 AM CDT | Severe Thunderstorm Warning | DMX | 38 min |
| Jul 25, 2:47 PM CDT | Heat Advisory | DMX | 3 days |
| Jul 26, 4:26 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 27, 3:19 AM CDT | Excessive Heat Warning | DMX | 42 hr |
| Jul 28, 3:55 PM CDT | Mesoscale Discussion | SPC | 95 min |
| Jul 28, 4:57 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 5, 3:01 PM CDT | Tornado Watch | SPC | 7 hr |
| Aug 5, 5:02 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Aug 5, 6:30 PM CDT | Tornado Warning | DMX | 30 min |
| Aug 5, 7:53 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 5, 9:28 PM CDT | Severe Thunderstorm Warning | DMX | 47 min |
| Aug 11, 9:57 PM CDT | Severe Thunderstorm Warning | DMX | 21 min |
| Aug 17, 3:07 PM CDT | Excessive Heat Watch | DMX | 71 hr |
| Aug 18, 2:18 PM CDT | Excessive Heat Warning | DMX | 7 days |
| Aug 18, 2:18 PM CDT | Heat Advisory | DMX | 31 hr |
| Aug 21, 2:56 PM CDT | Excessive Heat Watch | DMX | 24 hr |
| Sep 23, 9:37 AM CDT | Mesoscale Discussion | SPC | 113 min |
| Sep 23, 12:23 PM CDT | Severe Thunderstorm Warning | DMX | 67 min |
| Sep 23, 1:34 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Sep 23, 6:23 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 27, 4:29 AM CDT | Dense Fog Advisory | DMX | 6 hr |
| Sep 28, 6:09 AM CDT | Dense Fog Advisory | DMX | 4 hr |
| Oct 6, 2:31 AM CDT | Frost Advisory | DMX | 30 hr |
| Oct 9, 2:23 PM CDT | Frost Advisory | DMX | 19 hr |
| Oct 11, 8:50 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 23, 9:27 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 30, 3:33 PM CDT | Wind Advisory | DMX | 21 hr |
| Dec 22, 3:20 PM CST | Dense Fog Advisory | DMX | 20 hr |
| Dec 23, 10:59 AM CST | Dense Fog Advisory | DMX | 2 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 | 8 |
| Tornado Warning | 4 |
| Severe Thunderstorm Watch | 7 |
| Tornado Watch | 3 |
| Mesoscale Discussion | 20 |
| Special Weather Statement | 1 |
| Winter | |
| Ice Storm Warning | 1 |
| Winter Storm Warning | 2 |
| Winter Storm Watch | 2 |
| Winter Weather Advisory | 5 |
| Heat | |
| Excessive Heat Warning | 2 |
| Excessive Heat Watch | 2 |
| Heat Advisory | 2 |
| Cold | |
| Frost Advisory | 2 |
| Wind Chill Advisory | 4 |
| Wind and dust | |
| Wind Advisory | 5 |
| Fire | |
| Red Flag Warning | 3 |
| Fire Weather Watch | 3 |
| Fog and smoke | |
| Dense Fog Advisory | 8 |
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.