Alert archive / Iowa / Iowa County
Weather alerts in Iowa County, Iowa, 2011
127 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Iowa County and its neighbors
Each county as a circle sized by its count in 2011. Tap one for its archive.
- Alerts
- 127
- Warnings
- 35
- Watches
- 16
- Advisories
- 28
- Busiest month
- June30 alerts
- Busiest day
- May 22, 201114 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
3 of 4 tornado warnings covering Iowa County in 2011 had a tornado report inside them; 2 of 3 tornado reports fell inside a warning, on average 17 minutes after it went out.
Iowa County, 2011
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 4 | 3 | 25% | 3 | 67% | 17 min |
| Severe thunderstorm warnings | 21 | 13 | 38% | 13 | 46% | 22 min |
| Flash flood warnings | 2 | 2 | 0% | 0 |
Each office's whole area, 2011
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Quad Cities, IA: tornado warnings | 15 | 7 | 53% | 14 | 71% | 15 min |
| NWS Quad Cities, IA: severe thunderstorm warnings | 157 | 110 | 30% | 411 | 81% | 27 min |
| NWS Quad Cities, IA: flash flood warnings | 30 | 23 | 23% | 69 | 77% | 164 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, 4:17 AM CST | Winter Weather Advisory | DVN | 38 hr |
| Jan 16, 3:50 PM CST | Winter Weather Advisory | DVN | 28 hr |
| Jan 20, 3:02 AM CST | Wind Chill Advisory | DVN | 31 hr |
| Jan 30, 3:40 AM CST | Winter Storm Watch | DVN | 37 hr |
| Jan 31, 4:12 PM CST | Blizzard Warning | DVN | 44 hr |
| Feb 1, 10:36 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Feb 1, 3:36 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Feb 2, 3:38 PM CST | Wind Chill Advisory | DVN | 19 hr |
| Feb 7, 3:31 PM CST | Wind Chill Advisory | DVN | 20 hr |
| Feb 8, 3:37 PM CST | Wind Chill Advisory | DVN | 18 hr |
| Feb 9, 2:41 PM CST | Wind Chill Advisory | DVN | 19 hr |
| Feb 16, 5:00 AM CST | Dense Fog Advisory | DVN | 8 hr |
| Feb 16, 8:25 PM CST | Dense Fog Advisory | DVN | 6 hr |
| Feb 17, 9:02 AM CST | River Flood Warning | DVN | 7 days |
| Feb 24, 3:20 AM CST | Winter Weather Advisory | DVN | 26 hr |
| Feb 27, 3:37 PM CST | Winter Weather Advisory | DVN | 11 hr |
| Feb 27, 5:50 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Mar 11, 3:29 AM CST | Dense Fog Advisory | DVN | 7 hr |
| Mar 20, 2:51 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Mar 21, 1:10 PM CDT | Special Weather Statement | DVN | 80 min |
| Mar 22, 8:58 PM CDT | Special Weather Statement | DVN | 62 min |
| Mar 22, 9:38 PM CDT | Special Weather Statement | DVN | 52 min |
| Mar 22, 9:42 PM CDT | Severe Thunderstorm Warning | DVN | 63 min |
| Apr 3, 4:49 PM CDT | Mesoscale Discussion | SPC | 56 min |
| Apr 3, 5:57 PM CDT | Tornado Watch | SPC | 6 hr |
| Apr 3, 6:06 PM CDT | Severe Thunderstorm Warning | DVN | 39 min |
| Apr 3, 6:30 PM CDT | Severe Thunderstorm Warning | DVN | 45 min |
| Apr 3, 7:13 PM CDT | Severe Thunderstorm Warning | DVN | 51 min |
| Apr 3, 7:44 PM CDT | Mesoscale Discussion | SPC | 61 min |
| Apr 4, 11:58 AM CDT | Wind Advisory | DVN | 6 hr |
| Apr 10, 3:55 AM CDT | Wind Advisory | DVN | 12 hr |
| Apr 15, 4:30 AM CDT | Wind Advisory | DVN | 15 hr |
| Apr 26, 9:32 PM CDT | River Flood Warning | DVN | 5 days |
| May 2, 3:33 PM CDT | Frost Advisory | DVN | 15 hr |
| May 3, 3:15 PM CDT | Freeze Warning | DVN | 16 hr |
| May 11, 8:09 AM CDT | Mesoscale Discussion | SPC | 66 min |
| May 11, 1:23 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 11, 3:38 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 11, 8:49 PM CDT | Special Weather Statement | DVN | 56 min |
| May 16, 2:57 PM CDT | Frost Advisory | DVN | 16 hr |
| May 21, 10:09 PM CDT | Special Weather Statement | DVN | 51 min |
| May 22, 4:41 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 22, 10:53 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 22, 12:51 PM CDT | Tornado Watch | SPC | 10 hr |
| May 22, 2:01 PM CDT | Severe Thunderstorm Warning | DVN | 44 min |
| May 22, 2:06 PM CDT | Severe Thunderstorm Warning | DVN | 54 min |
| May 22, 2:34 PM CDT | Severe Thunderstorm Warning | DVN | 33 min |
| May 22, 2:38 PM CDT | Tornado Warning | DVN | 67 min |
| May 22, 2:45 PM CDT | Tornado Warning | DVN | 29 min |
| May 22, 2:59 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 22, 3:22 PM CDT | Tornado Warning | DVN | 53 min |
| May 22, 3:25 PM CDT | Severe Thunderstorm Warning | DVN | 65 min |
| May 22, 3:43 PM CDT | Severe Thunderstorm Warning | DVN | 47 min |
| May 22, 4:17 PM CDT | Severe Thunderstorm Warning | DVN | 43 min |
| May 24, 4:13 PM CDT | Special Weather Statement | DVN | 62 min |
| May 24, 4:44 PM CDT | Severe Thunderstorm Warning | DVN | 61 min |
| May 25, 3:46 AM CDT | Special Weather Statement | DVN | 59 min |
| May 25, 6:37 AM CDT | River Flood Warning | DVN | 7 days |
| May 25, 2:31 PM CDT | Wind Advisory | DVN | 7 hr |
| May 29, 5:05 AM CDT | Dense Fog Advisory | DVN | 4 hr |
| May 29, 8:39 AM CDT | Mesoscale Discussion | SPC | 66 min |
| May 29, 8:53 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 5, 6:22 AM CDT | Severe Thunderstorm Warning | DVN | 53 min |
| Jun 5, 9:02 AM CDT | Special Weather Statement | DVN | 43 min |
| Jun 5, 5:17 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jun 6, 3:28 AM CDT | Heat Advisory | DVN | 64 hr |
| Jun 8, 3:36 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Jun 8, 4:49 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 8, 8:32 PM CDT | Severe Thunderstorm Warning | DVN | 13 min |
| Jun 8, 8:43 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Jun 8, 8:57 PM CDT | Severe Thunderstorm Warning | DVN | 63 min |
| Jun 8, 9:00 PM CDT | Severe Thunderstorm Warning | DVN | 28 min |
| Jun 9, 1:44 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 9, 3:12 AM CDT | Flash Flood Watch | DVN | 28 hr |
| Jun 10, 1:39 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 10, 2:26 AM CDT | Flash Flood Warning | DVN | 5 hr |
| Jun 10, 9:04 AM CDT | River Flood Warning | DVN | 5 days |
| Jun 13, 1:46 PM CDT | Special Weather Statement | DVN | 59 min |
| Jun 13, 3:47 PM CDT | Flash Flood Watch | DVN | 39 hr |
| Jun 13, 9:23 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Jun 14, 10:36 PM CDT | Flash Flood Warning | DVN | 9 hr |
| Jun 15, 7:21 AM CDT | Areal Flood Warning | DVN | 5 hr |
| Jun 19, 11:42 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 20, 1:51 AM CDT | Special Weather Statement | DVN | 39 min |
| Jun 20, 4:08 AM CDT | Mesoscale Discussion | SPC | 67 min |
| Jun 20, 10:22 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 21, 1:25 AM CDT | Mesoscale Discussion | SPC | 35 min |
| Jun 22, 8:35 PM CDT | River Flood Warning | DVN | 38 hr |
| Jun 26, 10:02 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jun 26, 10:48 PM CDT | Severe Thunderstorm Warning | DVN | 57 min |
| Jun 29, 3:18 PM CDT | Excessive Heat Watch | DVN | 13 hr |
| Jun 30, 3:55 AM CDT | Heat Advisory | DVN | 44 hr |
| Jul 10, 10:35 AM CDT | Special Weather Statement | DVN | 55 min |
| Jul 11, 2:36 AM CDT | Mesoscale Discussion | SPC | 114 min |
| Jul 11, 3:30 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 11, 4:20 AM CDT | Severe Thunderstorm Warning | DVN | 55 min |
| Jul 11, 4:55 AM CDT | Severe Thunderstorm Warning | DVN | 65 min |
| Jul 11, 5:07 AM CDT | Mesoscale Discussion | SPC | 113 min |
| Jul 14, 3:40 PM CDT | Excessive Heat Watch | DVN | 24 hr |
| Jul 15, 3:42 PM CDT | Excessive Heat Warning | DVN | 9 days |
| Jul 22, 4:18 AM CDT | Special Weather Statement | DVN | 57 min |
| Jul 22, 7:38 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Jul 22, 10:54 PM CDT | Special Weather Statement | DVN | 51 min |
| Jul 23, 2:32 PM CDT | Flash Flood Watch | DVN | 14 hr |
| Jul 26, 10:53 AM CDT | Heat Advisory | DVN | 10 hr |
| Jul 27, 3:44 AM CDT | Heat Advisory | DVN | 18 hr |
| Jul 31, 3:54 AM CDT | Heat Advisory | DVN | 66 hr |
| Aug 2, 3:50 AM CDT | Excessive Heat Warning | DVN | 18 hr |
| Aug 2, 12:57 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Aug 6, 8:10 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 6, 10:14 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 7, 12:20 AM CDT | Severe Thunderstorm Warning | DVN | 55 min |
| Aug 8, 1:06 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Aug 8, 1:55 PM CDT | Special Weather Statement | DVN | 50 min |
| Aug 23, 12:45 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 1, 10:40 AM CDT | Heat Advisory | DVN | 32 hr |
| Sep 2, 2:41 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Sep 2, 10:04 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Sep 2, 10:23 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Sep 2, 11:56 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Sep 14, 3:48 AM CDT | Frost Advisory | DVN | 28 hr |
| Sep 25, 5:24 PM CDT | Special Weather Statement | DVN | 51 min |
| Sep 28, 3:57 PM CDT | Wind Advisory | DVN | 27 hr |
| Oct 12, 7:24 AM CDT | Special Weather Statement | DVN | 51 min |
| Oct 12, 9:52 AM CDT | Special Weather Statement | DVN | 2 hr |
| Oct 20, 3:20 AM CDT | Freeze Warning | DVN | 30 hr |
| Dec 6, 7:45 AM CST | Winter Weather Advisory | DVN | 6 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 | 3 |
| Severe Thunderstorm Watch | 8 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 31 |
| Special Weather Statement | 17 |
| Flooding | |
| Areal Flood Warning | 1 |
| Flash Flood Warning | 2 |
| River Flood Warning | 5 |
| Flash Flood Watch | 3 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Watch | 1 |
| Winter Weather Advisory | 5 |
| Heat | |
| Excessive Heat Warning | 2 |
| Excessive Heat Watch | 2 |
| Heat Advisory | 6 |
| Cold | |
| Freeze Warning | 2 |
| Frost Advisory | 3 |
| Wind Chill Advisory | 5 |
| Wind and dust | |
| Wind Advisory | 5 |
| Fog and smoke | |
| Dense Fog Advisory | 4 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20102012
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.