Alert archive / Iowa / Cass County
Weather alerts in Cass County, Iowa, 2025
139 weather alerts in 2025, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Cass County and its neighbors
Each county as a circle sized by its count in 2025. Tap one for its archive.
- Alerts
- 139
- Warnings
- 41
- Watches
- 25
- Advisories
- 39
- Busiest month
- July28 alerts
- Busiest day
- March 14, 20255 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
0 of 2 tornado warnings covering Cass County in 2025 had a tornado report inside them.
Cass County, 2025
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 2 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 22 | 16 | 27% | 7 | 100% | 9 min |
| Flash flood warnings | 1 | 0 | 100% | 0 |
Each office's whole area, 2025
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Des Moines, IA: tornado warnings | 24 | 1 | 96% | 5 | 20% | 0 min |
| NWS Des Moines, IA: severe thunderstorm warnings | 254 | 125 | 51% | 349 | 78% | 23 min |
| NWS Des Moines, IA: flash flood warnings | 18 | 7 | 61% | 11 | 82% | 79 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, 2:36 PM CST | Winter Weather Advisory | DMX | 24 hr |
| Jan 2, 5:50 AM CST | Mesoscale Discussion | SPC | 3 hr |
| Jan 2, 6:27 AM CST | Snow Squall Warning | DMX | 63 min |
| Jan 17, 2:37 PM CST | Cold Weather Advisory | DMX | 45 hr |
| Jan 19, 2:48 AM CST | Cold Weather Advisory | DMX | 32 hr |
| Jan 20, 2:46 AM CST | Cold Weather Advisory | DMX | 33 hr |
| Jan 20, 2:46 AM CST | Extreme Cold Warning | DMX | 33 hr |
| Feb 2, 3:55 AM CST | Dense Fog Advisory | DMX | 7 hr |
| Feb 4, 1:55 PM CST | Winter Weather Advisory | DMX | 34 hr |
| Feb 7, 8:26 PM CST | Winter Weather Advisory | DMX | 9 hr |
| Feb 11, 2:50 AM CST | Winter Storm Warning | DMX | 42 hr |
| Feb 11, 2:50 AM CST | Winter Weather Advisory | DMX | 42 hr |
| Feb 12, 2:32 AM CST | Cold Weather Advisory | DMX | 30 hr |
| Feb 14, 12:11 PM CST | Winter Weather Advisory | DMX | 26 hr |
| Feb 16, 3:18 AM CST | Extreme Cold Watch | DMX | 24 hr |
| Feb 16, 3:21 AM CST | Winter Weather Advisory | DMX | 39 hr |
| Feb 17, 3:44 AM CST | Cold Weather Advisory | DMX | 32 hr |
| Feb 17, 3:44 AM CST | Extreme Cold Warning | DMX | 32 hr |
| Feb 18, 3:24 AM CST | Cold Weather Advisory | DMX | 33 hr |
| Feb 19, 3:37 AM CST | Extreme Cold Warning | DMX | 29 hr |
| Feb 20, 2:39 AM CST | Cold Weather Advisory | DMX | 30 hr |
| Feb 27, 2:09 PM CST | Red Flag Warning | DMX | 28 hr |
| Mar 3, 2:56 AM CST | Winter Storm Watch | DMX | 24 hr |
| Mar 3, 2:39 PM CST | High Wind Watch | DMX | 12 hr |
| Mar 4, 2:36 AM CST | High Wind Warning | DMX | 36 hr |
| Mar 4, 11:51 AM CST | Blizzard Warning | DMX | 27 hr |
| Mar 4, 12:40 PM CST | High Wind Warning | DMX | 29 hr |
| Mar 4, 7:20 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Mar 4, 11:17 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Mar 5, 2:43 PM CST | Wind Advisory | DMX | 3 hr |
| Mar 9, 4:10 AM CDT | Fire Weather Watch | DMX | 10 hr |
| Mar 9, 2:20 PM CDT | Red Flag Warning | DMX | 30 hr |
| Mar 14, 3:19 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Mar 14, 4:04 PM CDT | Severe Thunderstorm Warning | DMX | 41 min |
| Mar 14, 4:57 PM CDT | Severe Thunderstorm Warning | DMX | 48 min |
| Mar 14, 5:01 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Mar 14, 5:19 PM CDT | Severe Thunderstorm Warning | DMX | 41 min |
| Mar 16, 2:19 PM CDT | Fire Weather Watch | DMX | 13 hr |
| Mar 17, 2:50 AM CDT | Red Flag Warning | DMX | 17 hr |
| Mar 17, 3:28 AM CDT | Winter Storm Watch | DMX | 36 hr |
| Mar 17, 2:50 PM CDT | High Wind Watch | DMX | 24 hr |
| Mar 18, 4:10 AM CDT | High Wind Warning | DMX | 42 hr |
| Mar 18, 3:06 PM CDT | Winter Weather Advisory | DMX | 30 hr |
| Mar 29, 7:52 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 1, 8:56 PM CDT | Mesoscale Discussion | SPC | 64 min |
| Apr 1, 11:48 PM CDT | Special Weather Statement | DMX | 42 min |
| Apr 2, 3:05 AM CDT | Wind Advisory | DMX | 16 hr |
| Apr 14, 5:35 PM CDT | Special Weather Statement | DMX | 85 min |
| Apr 17, 4:48 PM CDT | Tornado Watch | SPC | 7 hr |
| Apr 17, 7:37 PM CDT | Mesoscale Discussion | SPC | 53 min |
| Apr 17, 8:10 PM CDT | Severe Thunderstorm Warning | DMX | 65 min |
| Apr 17, 8:23 PM CDT | Tornado Warning | DMX | 40 min |
| Apr 17, 9:12 PM CDT | Severe Thunderstorm Warning | DMX | 48 min |
| Apr 23, 4:43 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Apr 23, 6:06 PM CDT | Severe Thunderstorm Warning | DMX | 39 min |
| Apr 23, 6:43 PM CDT | Severe Thunderstorm Warning | DMX | 47 min |
| Apr 24, 4:35 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Apr 28, 3:28 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 28, 4:58 PM CDT | Tornado Watch | SPC | 7 hr |
| Apr 28, 8:40 PM CDT | Severe Thunderstorm Warning | DMX | 39 min |
| Apr 28, 8:54 PM CDT | Tornado Warning | DMX | 26 min |
| Apr 28, 8:58 PM CDT | Severe Thunderstorm Warning | DMX | 47 min |
| May 15, 2:27 PM CDT | Wind Advisory | DMX | 31 hr |
| May 19, 3:31 PM CDT | Mesoscale Discussion | SPC | 89 min |
| May 19, 3:43 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 19, 6:08 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 15, 8:48 PM CDT | Severe Thunderstorm Warning | DMX | 31 min |
| Jun 16, 5:11 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 16, 7:16 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Jun 16, 9:04 PM CDT | Severe Thunderstorm Warning | DMX | 30 min |
| Jun 18, 1:43 PM CDT | Extreme Heat Watch | DMX | 38 hr |
| Jun 19, 1:55 PM CDT | Extreme Heat Warning | DMX | 3 days |
| Jun 23, 2:34 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 23, 4:09 PM CDT | Severe Thunderstorm Warning | DMX | 51 min |
| Jun 23, 4:39 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jun 23, 4:58 PM CDT | Severe Thunderstorm Warning | DMX | 47 min |
| Jun 25, 5:13 AM CDT | Flash Flood Warning | DMX | 5 hr |
| Jun 26, 12:36 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Jun 26, 1:44 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 7, 9:04 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 7, 10:44 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Jul 7, 11:20 PM CDT | Severe Thunderstorm Warning | DMX | 25 min |
| Jul 7, 11:40 PM CDT | Severe Thunderstorm Warning | DMX | 50 min |
| Jul 10, 1:39 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 10, 3:57 AM CDT | Mesoscale Discussion | SPC | 93 min |
| Jul 10, 1:17 PM CDT | Flood Watch | DMX | 30 hr |
| Jul 10, 7:46 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jul 10, 10:47 PM CDT | Severe Thunderstorm Warning | DMX | 43 min |
| Jul 10, 10:51 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Jul 10, 11:10 PM CDT | Severe Thunderstorm Warning | DMX | 35 min |
| Jul 10, 11:20 PM CDT | Severe Thunderstorm Warning | DMX | 55 min |
| Jul 15, 10:45 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 19, 2:48 PM CDT | Flood Watch | DMX | 18 hr |
| Jul 22, 2:02 PM CDT | Heat Advisory | DMX | 30 hr |
| Jul 24, 12:23 AM CDT | Severe Thunderstorm Warning | DMX | 52 min |
| Jul 25, 2:59 AM CDT | Dense Fog Advisory | DMX | 4 hr |
| Jul 26, 2:36 AM CDT | Extreme Heat Watch | DMX | 11 hr |
| Jul 26, 2:04 PM CDT | Heat Advisory | DMX | 30 hr |
| Jul 27, 2:43 PM CDT | Extreme Heat Warning | DMX | 29 hr |
| Jul 28, 1:34 AM CDT | Mesoscale Discussion | SPC | 86 min |
| Jul 28, 2:34 PM CDT | Heat Advisory | DMX | 29 hr |
| Jul 29, 3:08 PM CDT | Flood Watch | DMX | 23 hr |
| Jul 29, 9:26 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Jul 29, 11:55 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 30, 1:23 AM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 30, 1:25 AM CDT | Severe Thunderstorm Warning | DMX | 46 min |
| Jul 30, 1:28 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 7, 2:42 PM CDT | Heat Advisory | DMX | 28 hr |
| Aug 9, 5:31 AM CDT | Mesoscale Discussion | SPC | 89 min |
| Aug 9, 6:04 AM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 9, 7:29 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 10, 1:44 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 10, 2:51 AM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Aug 10, 3:48 AM CDT | Severe Thunderstorm Warning | DMX | 42 min |
| Aug 10, 4:17 AM CDT | Severe Thunderstorm Warning | DMX | 43 min |
| Aug 10, 4:59 AM CDT | Mesoscale Discussion | SPC | 91 min |
| Aug 14, 2:31 PM CDT | Heat Advisory | DMX | 28 hr |
| Aug 15, 2:51 PM CDT | Heat Advisory | DMX | 29 hr |
| Aug 19, 1:32 AM CDT | Dense Fog Advisory | DMX | 7 hr |
| Sep 16, 2:21 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Sep 16, 6:46 PM CDT | Special Weather Statement | DMX | 14 min |
| Sep 21, 3:33 AM CDT | Dense Fog Advisory | DMX | 5 hr |
| Sep 22, 8:51 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Oct 21, 2:00 PM CDT | Frost Advisory | DMX | 19 hr |
| Oct 22, 2:20 AM CDT | Frost Advisory | DMX | 31 hr |
| Oct 22, 2:31 PM CDT | Freeze Warning | DMX | 18 hr |
| Oct 30, 1:33 AM CDT | Dense Fog Advisory | DMX | 9 hr |
| Nov 20, 5:01 AM CST | Dense Fog Advisory | DMX | 7 hr |
| Nov 24, 2:32 PM CST | Wind Advisory | DMX | 44 hr |
| Nov 25, 12:21 AM CST | Dense Fog Advisory | DMX | 10 hr |
| Nov 27, 3:21 AM CST | Winter Storm Watch | DMX | 23 hr |
| Nov 27, 2:19 PM CST | Winter Storm Warning | DMX | 60 hr |
| Nov 29, 4:49 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Dec 9, 2:59 AM CST | Wind Advisory | DMX | 30 hr |
| Dec 17, 2:58 AM CST | Wind Advisory | DMX | 45 hr |
| Dec 24, 4:34 PM CST | Dense Fog Advisory | DMX | 43 hr |
| Dec 26, 4:44 PM CST | Dense Fog Advisory | DMX | 40 hr |
| Dec 27, 2:36 PM CST | Winter Weather Advisory | DMX | 42 hr |
| Dec 27, 2:42 PM CST | Wind Advisory | DMX | 39 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.