Alert archive / Iowa / Polk County
Weather alerts in Polk County, Iowa, 2013
124 weather alerts in 2013, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Polk County and its neighbors
Each county as a circle sized by its count in 2013. Tap one for its archive.
- Alerts
- 124
- Warnings
- 46
- Watches
- 23
- Advisories
- 27
- Busiest month
- May38 alerts
- Busiest day
- October 4, 201311 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 4 tornado warnings covering Polk County in 2013 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 21 minutes after it went out.
Polk County, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 4 | 1 | 75% | 1 | 100% | 21 min |
| Severe thunderstorm warnings | 22 | 13 | 41% | 57 | 84% | 22 min |
| Flash flood warnings | 2 | 2 | 0% | 2 | 50% | 157 min |
Each office's whole area, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Des Moines, IA: tornado warnings | 26 | 6 | 77% | 20 | 80% | 13 min |
| NWS Des Moines, IA: severe thunderstorm warnings | 252 | 131 | 48% | 422 | 76% | 21 min |
| NWS Des Moines, IA: flash flood warnings | 54 | 31 | 43% | 96 | 90% | 123 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 10, 3:31 PM CST | Dense Fog Advisory | DMX | 29 hr |
| Jan 18, 12:07 PM CST | Wind Advisory | DMX | 5 hr |
| Jan 20, 3:54 PM CST | Wind Chill Advisory | DMX | 42 hr |
| Jan 26, 3:35 AM CST | Freezing Rain Advisory | DMX | 41 hr |
| Jan 27, 6:40 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Jan 27, 8:56 PM CST | Dense Fog Advisory | DMX | 33 hr |
| Jan 29, 3:59 AM CST | Winter Storm Watch | DMX | 8 hr |
| Jan 29, 12:01 PM CST | Winter Storm Warning | DMX | 24 hr |
| Jan 30, 3:18 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Jan 30, 3:54 AM CST | Wind Chill Advisory | DMX | 56 hr |
| Feb 10, 3:32 PM CST | Wind Advisory | DMX | 24 hr |
| Feb 19, 4:01 AM CST | Winter Storm Watch | DMX | 35 hr |
| Feb 20, 3:44 AM CST | Winter Storm Warning | DMX | 56 hr |
| Feb 25, 4:15 PM CST | Winter Storm Warning | DMX | 44 hr |
| Feb 25, 4:15 PM CST | Winter Weather Advisory | DMX | 18 hr |
| Mar 3, 3:18 PM CST | Winter Weather Advisory | DMX | 19 hr |
| Mar 4, 3:20 PM CST | Winter Weather Advisory | DMX | 24 hr |
| Mar 9, 3:17 PM CST | Winter Storm Watch | DMX | 12 hr |
| Mar 9, 7:01 PM CST | Dense Fog Advisory | DMX | 11 hr |
| Mar 10, 4:21 AM CDT | Winter Storm Warning | DMX | 29 hr |
| Mar 10, 4:21 AM CDT | Winter Weather Advisory | DMX | 32 hr |
| Mar 30, 10:14 PM CDT | Dense Fog Advisory | DMX | 11 hr |
| Apr 9, 5:12 AM CDT | Mesoscale Discussion | SPC | 93 min |
| Apr 9, 7:37 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Apr 14, 3:28 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Apr 29, 7:26 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Apr 29, 10:21 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| May 1, 4:13 PM CDT | Winter Weather Advisory | DMX | 44 hr |
| May 11, 4:02 AM CDT | Frost Advisory | DMX | 28 hr |
| May 19, 11:30 AM CDT | Mesoscale Discussion | SPC | 90 min |
| May 19, 2:59 PM CDT | Tornado Watch | SPC | 8 hr |
| May 19, 6:42 PM CDT | Severe Thunderstorm Warning | DMX | 48 min |
| May 19, 6:49 PM CDT | Tornado Warning | DMX | 26 min |
| May 19, 7:13 PM CDT | Mesoscale Discussion | SPC | 62 min |
| May 19, 7:14 PM CDT | Tornado Warning | DMX | 46 min |
| May 19, 7:16 PM CDT | Severe Thunderstorm Warning | DMX | 29 min |
| May 19, 7:55 PM CDT | Severe Thunderstorm Warning | DMX | 35 min |
| May 20, 5:38 PM CDT | Mesoscale Discussion | SPC | 67 min |
| May 20, 6:35 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| May 20, 6:54 PM CDT | Severe Thunderstorm Warning | DMX | 36 min |
| May 20, 7:10 PM CDT | Tornado Warning | DMX | 35 min |
| May 20, 7:39 PM CDT | Tornado Warning | DMX | 36 min |
| May 20, 8:45 PM CDT | Severe Thunderstorm Warning | DMX | 30 min |
| May 25, 3:39 PM CDT | Flash Flood Watch | DMX | 21 hr |
| May 26, 3:51 PM CDT | Flash Flood Watch | DMX | 41 hr |
| May 27, 2:51 AM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| May 27, 10:08 AM CDT | High Wind Warning | DMX | 76 min |
| May 27, 10:19 AM CDT | River Flood Warning | DMX | 64 hr |
| May 27, 10:19 AM CDT | River Flood Warning | DMX | 5 days |
| May 27, 10:19 AM CDT | River Flood Warning | DMX | 8 days |
| May 27, 11:12 AM CDT | River Flood Warning | DMX | 5 days |
| May 27, 11:12 AM CDT | River Flood Warning | DMX | 5 days |
| May 27, 11:12 AM CDT | River Flood Warning | DMX | 8 days |
| May 28, 1:37 PM CDT | Mesoscale Discussion | SPC | 113 min |
| May 29, 8:54 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 29, 11:01 AM CDT | Flash Flood Watch | DMX | 56 hr |
| May 29, 2:26 PM CDT | Severe Thunderstorm Warning | DMX | 34 min |
| May 29, 2:55 PM CDT | Severe Thunderstorm Warning | DMX | 35 min |
| May 29, 2:56 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 29, 3:25 PM CDT | Severe Thunderstorm Warning | DMX | 65 min |
| May 29, 3:30 PM CDT | Flash Flood Warning | DMX | 6 hr |
| May 29, 4:13 PM CDT | Flash Flood Warning | DMX | 3 hr |
| May 29, 5:54 PM CDT | Mesoscale Discussion | SPC | 66 min |
| May 29, 6:55 PM CDT | Areal Flood Warning | DMX | 12 hr |
| May 29, 8:54 PM CDT | River Flood Warning | DMX | 59 hr |
| Jun 10, 4:54 AM CDT | Dense Fog Advisory | DMX | 4 hr |
| Jun 14, 3:53 AM CDT | Flash Flood Watch | DMX | 39 hr |
| Jun 14, 9:02 PM CDT | Mesoscale Discussion | SPC | 58 min |
| Jun 14, 9:16 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jun 14, 11:13 PM CDT | Severe Thunderstorm Warning | DMX | 47 min |
| Jun 15, 10:26 AM CDT | River Flood Warning | DMX | 5 days |
| Jun 15, 10:26 AM CDT | River Flood Warning | DMX | 5 days |
| Jun 23, 3:45 AM CDT | Flash Flood Watch | DMX | 12 hr |
| Jun 23, 7:54 PM CDT | Mesoscale Discussion | SPC | 96 min |
| Jun 24, 3:41 AM CDT | Flash Flood Watch | DMX | 51 hr |
| Jun 24, 11:30 AM CDT | Mesoscale Discussion | SPC | 30 min |
| Jun 24, 11:57 AM CDT | Severe Thunderstorm Warning | DMX | 48 min |
| Jun 24, 12:14 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 25, 8:23 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Jun 25, 9:44 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Jun 25, 10:41 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 2, 3:54 PM CDT | Severe Thunderstorm Warning | DMX | 21 min |
| Jul 8, 3:09 PM CDT | Heat Advisory | DMX | 27 hr |
| Jul 22, 3:08 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jul 22, 8:27 PM CDT | Severe Thunderstorm Warning | DMX | 48 min |
| Jul 22, 9:06 PM CDT | Severe Thunderstorm Warning | DMX | 54 min |
| Jul 22, 9:07 PM CDT | Wind Advisory | DMX | 98 min |
| Jul 25, 7:04 PM CDT | Mesoscale Discussion | SPC | 116 min |
| Aug 6, 5:58 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 6, 6:51 PM CDT | Severe Thunderstorm Watch | SPC | 3 hr |
| Aug 6, 9:37 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Aug 25, 3:24 AM CDT | Heat Advisory | DMX | 6 days |
| Aug 25, 9:23 PM CDT | Excessive Heat Warning | DMX | 5 days |
| Sep 19, 1:19 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Sep 19, 2:43 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Sep 19, 3:35 PM CDT | Severe Thunderstorm Warning | DMX | 40 min |
| Sep 19, 4:09 PM CDT | Severe Thunderstorm Warning | DMX | 66 min |
| Sep 19, 4:29 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Sep 19, 4:34 PM CDT | Severe Thunderstorm Warning | DMX | 41 min |
| Sep 19, 4:50 PM CDT | Severe Thunderstorm Warning | DMX | 40 min |
| Oct 3, 7:32 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 3, 8:16 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Oct 3, 11:42 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Oct 4, 2:06 AM CDT | Mesoscale Discussion | SPC | 84 min |
| Oct 4, 2:08 AM CDT | Severe Thunderstorm Warning | DMX | 67 min |
| Oct 4, 2:56 AM CDT | Severe Thunderstorm Warning | DMX | 34 min |
| Oct 4, 7:10 AM CDT | Severe Thunderstorm Warning | DMX | 50 min |
| Oct 4, 7:54 AM CDT | Severe Thunderstorm Warning | DMX | 36 min |
| Oct 4, 1:28 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 4, 2:23 PM CDT | Severe Thunderstorm Warning | DMX | 67 min |
| Oct 4, 6:42 PM CDT | Tornado Watch | SPC | 5 hr |
| Oct 4, 10:29 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Oct 22, 3:31 PM CDT | Freeze Warning | DMX | 16 hr |
| Oct 30, 3:56 AM CDT | Dense Fog Advisory | DMX | 10 hr |
| Nov 2, 3:34 PM CDT | Wind Advisory | DMX | 27 hr |
| Nov 21, 12:03 PM CST | Winter Weather Advisory | DMX | 14 hr |
| Dec 3, 5:39 AM CST | Dense Fog Advisory | DMX | 33 hr |
| Dec 7, 3:42 PM CST | Winter Weather Advisory | DMX | 32 hr |
| Dec 19, 3:11 AM CST | Freezing Rain Advisory | DMX | 33 hr |
| Dec 19, 4:01 PM CST | Winter Storm Watch | DMX | 36 hr |
| Dec 20, 2:57 PM CST | Winter Storm Warning | DMX | 44 hr |
| Dec 21, 10:41 PM CST | Mesoscale Discussion | SPC | 5 hr |
| Dec 22, 3:16 PM CST | Wind Chill Advisory | DMX | 45 hr |
| Dec 28, 4:20 AM CST | Wind Chill Advisory | DMX | 47 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 | 22 |
| Tornado Warning | 4 |
| Severe Thunderstorm Watch | 11 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 28 |
| Flooding | |
| Areal Flood Warning | 1 |
| Flash Flood Warning | 2 |
| River Flood Warning | 9 |
| Flash Flood Watch | 6 |
| Winter | |
| Winter Storm Warning | 5 |
| Winter Storm Watch | 4 |
| Freezing Rain Advisory | 2 |
| Winter Weather Advisory | 7 |
| Heat | |
| Excessive Heat Warning | 1 |
| Heat Advisory | 2 |
| Cold | |
| Freeze Warning | 1 |
| Frost Advisory | 1 |
| Wind Chill Advisory | 4 |
| Wind and dust | |
| High Wind Warning | 1 |
| Wind Advisory | 4 |
| Fog and smoke | |
| Dense Fog Advisory | 7 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20122014
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.