Alert archive / Iowa / Mahaska County
Weather alerts in Mahaska County, Iowa, 2018
140 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Mahaska County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 140
- Warnings
- 40
- Watches
- 22
- Advisories
- 38
- Busiest month
- June23 alerts
- Busiest day
- July 19, 201811 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
4 of 9 tornado warnings covering Mahaska County in 2018 had a tornado report inside them; 2 of 2 tornado reports fell inside a warning, on average 9 minutes after it went out.
Mahaska County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 9 | 4 | 56% | 2 | 100% | 9 min |
| Severe thunderstorm warnings | 19 | 11 | 42% | 6 | 83% | 16 min |
| Flash flood warnings | 2 | 1 | 50% | 5 | 80% | 53 min |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Des Moines, IA: tornado warnings | 72 | 23 | 68% | 69 | 55% | 15 min |
| NWS Des Moines, IA: severe thunderstorm warnings | 308 | 143 | 54% | 427 | 74% | 22 min |
| NWS Des Moines, IA: flash flood warnings | 39 | 20 | 49% | 70 | 74% | 86 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 3, 3:46 AM CST | Wind Chill Advisory | DMX | 30 hr |
| Jan 5, 4:04 PM CST | Wind Chill Advisory | DMX | 18 hr |
| Jan 6, 3:45 AM CST | Winter Weather Advisory | DMX | 38 hr |
| Jan 10, 2:08 PM CST | Winter Weather Advisory | DMX | 28 hr |
| Jan 11, 9:36 AM CST | Mesoscale Discussion | SPC | 4 hr |
| Jan 14, 3:47 AM CST | Wind Chill Advisory | DMX | 56 hr |
| Jan 26, 10:53 AM CST | Wind Advisory | DMX | 5 hr |
| Feb 4, 2:32 PM CST | Winter Weather Advisory | DMX | 28 hr |
| Feb 5, 11:36 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Feb 7, 2:23 PM CST | Winter Weather Advisory | DMX | 40 hr |
| Feb 9, 3:05 PM CST | Winter Weather Advisory | DMX | 16 hr |
| Feb 10, 2:10 PM CST | Winter Weather Advisory | DMX | 16 hr |
| Feb 18, 3:45 AM CST | Winter Weather Advisory | DMX | 56 hr |
| Feb 21, 3:42 PM CST | Winter Weather Advisory | DMX | 35 hr |
| Feb 23, 3:24 PM CST | Winter Weather Advisory | DMX | 30 hr |
| Feb 28, 7:35 AM CST | Dense Fog Advisory | DMX | 3 hr |
| Mar 18, 2:12 AM CDT | Dense Fog Advisory | DMX | 8 hr |
| Mar 23, 4:00 AM CDT | Winter Weather Advisory | DMX | 39 hr |
| Mar 30, 3:19 PM CDT | Wind Advisory | DMX | 25 hr |
| Apr 3, 4:19 AM CDT | Wind Advisory | DMX | 21 hr |
| Apr 7, 3:05 PM CDT | Winter Weather Advisory | DMX | 40 hr |
| Apr 13, 2:19 PM CDT | Tornado Watch | SPC | 7 hr |
| Apr 13, 3:54 PM CDT | Winter Weather Advisory | DMX | 48 hr |
| Apr 27, 2:42 PM CDT | Red Flag Warning | DMX | 4 hr |
| May 1, 10:24 AM CDT | Mesoscale Discussion | SPC | 3 hr |
| May 1, 5:47 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 1, 7:55 PM CDT | Mesoscale Discussion | SPC | 95 min |
| May 1, 9:38 PM CDT | Mesoscale Discussion | SPC | 67 min |
| May 2, 5:08 PM CDT | Mesoscale Discussion | SPC | 97 min |
| May 2, 5:27 PM CDT | Tornado Watch | SPC | 8 hr |
| May 2, 8:00 PM CDT | Mesoscale Discussion | SPC | 90 min |
| May 3, 2:57 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 3, 7:43 PM CDT | Mesoscale Discussion | SPC | 62 min |
| May 12, 1:04 AM CDT | Mesoscale Discussion | SPC | 116 min |
| May 13, 1:09 PM CDT | Special Weather Statement | DMX | 51 min |
| May 22, 2:05 AM CDT | Dense Fog Advisory | DMX | 7 hr |
| May 26, 3:53 PM CDT | Severe Thunderstorm Warning | DMX | 37 min |
| May 28, 2:31 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 29, 3:54 PM CDT | Mesoscale Discussion | SPC | 96 min |
| Jun 6, 2:22 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Jun 6, 3:23 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 6, 6:20 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Jun 6, 6:43 PM CDT | Severe Thunderstorm Warning | DMX | 62 min |
| Jun 6, 7:15 PM CDT | Severe Thunderstorm Warning | DMX | 60 min |
| Jun 8, 12:51 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Jun 11, 11:04 PM CDT | Special Weather Statement | DMX | 56 min |
| Jun 14, 10:50 AM CDT | Severe Thunderstorm Warning | DMX | 16 min |
| Jun 14, 3:00 PM CDT | Heat Advisory | DMX | 4 days |
| Jun 18, 3:05 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 18, 3:41 PM CDT | Flash Flood Watch | DMX | 16 hr |
| Jun 18, 5:46 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Jun 20, 12:49 PM CDT | Severe Thunderstorm Warning | DMX | 41 min |
| Jun 20, 1:01 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 20, 3:04 PM CDT | Tornado Watch | SPC | 4 hr |
| Jun 20, 5:13 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 20, 5:34 PM CDT | Tornado Warning | DMX | 41 min |
| Jun 27, 3:29 PM CDT | Heat Advisory | DMX | 54 hr |
| Jun 28, 8:12 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 28, 10:57 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 28, 12:38 PM CDT | Severe Thunderstorm Warning | DMX | 67 min |
| Jun 28, 1:06 PM CDT | Severe Thunderstorm Warning | DMX | 54 min |
| Jun 30, 3:12 AM CDT | Heat Advisory | DMX | 16 hr |
| Jun 30, 9:58 PM CDT | Severe Thunderstorm Warning | DMX | 47 min |
| Jul 3, 2:39 PM CDT | Heat Advisory | DMX | 29 hr |
| Jul 11, 3:44 PM CDT | Heat Advisory | DMX | 28 hr |
| Jul 13, 3:31 AM CDT | Heat Advisory | DMX | 15 hr |
| Jul 13, 4:27 PM CDT | Special Weather Statement | DMX | 33 min |
| Jul 13, 4:38 PM CDT | Severe Thunderstorm Warning | DMX | 52 min |
| Jul 13, 4:44 PM CDT | Special Weather Statement | DMX | 61 min |
| Jul 13, 4:58 PM CDT | Severe Thunderstorm Warning | DMX | 62 min |
| Jul 15, 6:08 AM CDT | Dense Fog Advisory | DMX | 3 hr |
| Jul 19, 3:14 AM CDT | Special Weather Statement | DMX | 61 min |
| Jul 19, 2:32 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Jul 19, 3:11 PM CDT | Tornado Watch | SPC | 6 hr |
| Jul 19, 3:37 PM CDT | Tornado Warning | DMX | 23 min |
| Jul 19, 3:54 PM CDT | Tornado Warning | DMX | 36 min |
| Jul 19, 4:14 PM CDT | Tornado Warning | DMX | 31 min |
| Jul 19, 4:18 PM CDT | Severe Thunderstorm Warning | DMX | 42 min |
| Jul 19, 4:36 PM CDT | Tornado Warning | DMX | 24 min |
| Jul 19, 4:52 PM CDT | Tornado Warning | DMX | 38 min |
| Jul 19, 5:13 PM CDT | Tornado Warning | DMX | 47 min |
| Jul 19, 5:18 PM CDT | Mesoscale Discussion | SPC | 57 min |
| Aug 5, 6:28 AM CDT | Special Weather Statement | DMX | 62 min |
| Aug 5, 5:44 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 25, 3:19 AM CDT | Dense Fog Advisory | DMX | 6 hr |
| Aug 28, 4:34 PM CDT | Severe Thunderstorm Warning | DMX | 41 min |
| Aug 28, 4:45 PM CDT | Mesoscale Discussion | SPC | 60 min |
| Aug 28, 4:50 PM CDT | Severe Thunderstorm Warning | DMX | 40 min |
| Aug 28, 5:03 PM CDT | Severe Thunderstorm Warning | DMX | 42 min |
| Aug 28, 5:06 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 28, 5:17 PM CDT | Severe Thunderstorm Warning | DMX | 43 min |
| Aug 31, 10:55 PM CDT | Severe Thunderstorm Warning | DMX | 50 min |
| Sep 1, 1:01 AM CDT | Severe Thunderstorm Warning | DMX | 22 min |
| Sep 1, 4:38 AM CDT | Flash Flood Watch | DMX | 24 hr |
| Sep 1, 6:34 PM CDT | Mesoscale Discussion | SPC | 56 min |
| Sep 1, 8:16 PM CDT | Severe Thunderstorm Warning | DMX | 14 min |
| Sep 1, 8:20 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Sep 1, 9:59 PM CDT | Flash Flood Warning | DMX | 5 hr |
| Sep 1, 10:27 PM CDT | Mesoscale Discussion | SPC | 63 min |
| Sep 2, 9:45 AM CDT | Flash Flood Watch | DMX | 36 hr |
| Sep 2, 2:24 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 3, 5:47 PM CDT | Mesoscale Discussion | SPC | 58 min |
| Sep 3, 6:09 PM CDT | Tornado Watch | SPC | 2 hr |
| Sep 5, 7:12 AM CDT | Flash Flood Watch | DMX | 20 hr |
| Sep 5, 11:07 AM CDT | Flash Flood Warning | DMX | 4 hr |
| Sep 5, 3:53 PM CDT | Areal Flood Warning | DMX | 24 hr |
| Sep 6, 2:41 PM CDT | Areal Flood Warning | DMX | 24 hr |
| Sep 6, 3:01 PM CDT | Flash Flood Watch | DMX | 36 hr |
| Sep 18, 10:09 AM CDT | Special Weather Statement | DMX | 81 min |
| Sep 18, 11:25 AM CDT | Special Weather Statement | DMX | 65 min |
| Sep 25, 9:27 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 25, 1:07 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Oct 3, 12:07 PM CDT | Wind Advisory | DMX | 13 hr |
| Oct 4, 3:34 PM CDT | Flash Flood Watch | DMX | 45 hr |
| Oct 5, 2:39 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 6, 6:55 AM CDT | Areal Flood Warning | DMX | 12 hr |
| Oct 7, 3:52 PM CDT | Flood Watch | DMX | 60 hr |
| Oct 8, 10:40 AM CDT | Areal Flood Warning | DMX | 24 hr |
| Oct 8, 5:33 PM CDT | Tornado Watch | SPC | 4 hr |
| Oct 8, 9:54 PM CDT | Severe Thunderstorm Warning | DMX | 21 min |
| Oct 9, 1:48 AM CDT | Areal Flood Warning | DMX | 24 hr |
| Oct 9, 12:59 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 9, 1:46 PM CDT | Tornado Watch | SPC | 7 hr |
| Oct 9, 2:16 PM CDT | Tornado Warning | DMX | 29 min |
| Oct 9, 3:42 PM CDT | Tornado Warning | DMX | 22 min |
| Oct 9, 3:53 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 9, 6:37 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Oct 14, 3:45 AM CDT | Freeze Warning | DMX | 30 hr |
| Oct 15, 2:44 PM CDT | Freeze Warning | DMX | 18 hr |
| Oct 19, 7:30 PM CDT | Wind Advisory | DMX | 20 hr |
| Nov 3, 4:46 AM CDT | Dense Fog Advisory | DMX | 3 hr |
| Nov 17, 11:01 AM CST | Winter Weather Advisory | DMX | 16 hr |
| Nov 23, 3:30 AM CST | Winter Storm Watch | DMX | 24 hr |
| Nov 24, 3:40 AM CST | Winter Storm Warning | DMX | 11 hr |
| Nov 24, 2:34 PM CST | Blizzard Warning | DMX | 30 hr |
| Nov 30, 2:34 AM CST | Dense Fog Advisory | DMX | 7 hr |
| Dec 1, 6:56 AM CST | Wind Advisory | DMX | 7 hr |
| Dec 1, 12:55 PM CST | Dense Fog Advisory | DMX | 16 hr |
| Dec 28, 12:55 AM CST | Winter Weather Advisory | DMX | 11 hr |
| Dec 31, 3:26 AM CST | Winter Weather Advisory | DMX | 20 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 | 19 |
| Tornado Warning | 9 |
| Severe Thunderstorm Watch | 7 |
| Tornado Watch | 7 |
| Mesoscale Discussion | 32 |
| Special Weather Statement | 8 |
| Flooding | |
| Areal Flood Warning | 5 |
| Flash Flood Warning | 2 |
| Flash Flood Watch | 6 |
| Flood Watch | 1 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Warning | 1 |
| Winter Storm Watch | 1 |
| Winter Weather Advisory | 15 |
| Heat | |
| Heat Advisory | 6 |
| Cold | |
| Freeze Warning | 2 |
| Wind Chill Advisory | 3 |
| Wind and dust | |
| Wind Advisory | 6 |
| Fire | |
| Red Flag Warning | 1 |
| 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 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.