Alert archive / Iowa / Shelby County
Weather alerts in Shelby County, Iowa, 2015
120 weather alerts in 2015, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Shelby County and its neighbors
Each county as a circle sized by its count in 2015. Tap one for its archive.
- Alerts
- 120
- Warnings
- 22
- Watches
- 21
- Advisories
- 29
- Busiest month
- November22 alerts
- Busiest day
- November 11, 20156 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 1 tornado warnings covering Shelby County in 2015 had a tornado report inside them.
Shelby County, 2015
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 8 | 4 | 50% | 6 | 67% | 20 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2015
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Omaha, NE: tornado warnings | 22 | 7 | 68% | 10 | 80% | 11 min |
| NWS Omaha, NE: severe thunderstorm warnings | 262 | 116 | 56% | 220 | 82% | 18 min |
| NWS Omaha, NE: flash flood warnings | 26 | 11 | 58% | 30 | 97% | 88 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, 3:53 AM CST | Winter Weather Advisory | OAX | 25 hr |
| Jan 3, 11:51 AM CST | Wind Chill Advisory | OAX | 23 hr |
| Jan 5, 3:38 AM CST | Winter Weather Advisory | OAX | 14 hr |
| Jan 6, 2:37 PM CST | Wind Chill Warning | OAX | 21 hr |
| Jan 8, 3:34 AM CST | Winter Weather Advisory | OAX | 16 hr |
| Jan 8, 3:57 PM CST | Wind Chill Advisory | OAX | 17 hr |
| Jan 28, 3:15 PM CST | Wind Advisory | OAX | 16 hr |
| Jan 31, 5:11 AM CST | Winter Storm Warning | OAX | 37 hr |
| Jan 31, 5:11 AM CST | Winter Weather Advisory | OAX | 38 hr |
| Feb 6, 10:22 PM CST | Special Weather Statement | OAX | 3 hr |
| Feb 17, 3:15 PM CST | Wind Chill Advisory | OAX | 19 hr |
| Feb 19, 12:29 PM CST | Special Weather Statement | OAX | 16 min |
| Feb 24, 3:32 PM CST | Winter Weather Advisory | OAX | 25 hr |
| Feb 25, 3:25 AM CST | Winter Weather Advisory | OAX | 14 hr |
| Feb 25, 3:23 PM CST | Wind Chill Advisory | OAX | 19 hr |
| Mar 3, 7:06 AM CST | Freezing Rain Advisory | OAX | 3 hr |
| Mar 12, 3:29 AM CDT | Fire Weather Watch | OAX | 11 hr |
| Mar 14, 3:42 AM CDT | Fire Weather Watch | OAX | 24 hr |
| Mar 14, 3:08 PM CDT | Red Flag Warning | OAX | 29 hr |
| Mar 15, 3:48 AM CDT | Fire Weather Watch | OAX | 23 hr |
| Mar 16, 3:10 AM CDT | Red Flag Warning | OAX | 17 hr |
| Mar 20, 5:06 AM CDT | Dense Fog Advisory | OAX | 4 hr |
| Mar 24, 8:23 AM CDT | Special Weather Statement | OAX | 82 min |
| Mar 24, 10:44 AM CDT | Special Weather Statement | OAX | 91 min |
| Mar 28, 3:39 PM CDT | Wind Advisory | OAX | 23 hr |
| Mar 29, 3:56 AM CDT | Red Flag Warning | OAX | 12 hr |
| Mar 30, 3:54 AM CDT | Red Flag Warning | OAX | 15 hr |
| Apr 1, 12:35 PM CDT | Wind Advisory | OAX | 5 hr |
| Apr 1, 3:50 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Apr 1, 5:57 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Apr 1, 8:25 PM CDT | Mesoscale Discussion | SPC | 95 min |
| Apr 3, 3:26 PM CDT | Red Flag Warning | OAX | 29 hr |
| Apr 20, 3:47 AM CDT | Wind Advisory | OAX | 14 hr |
| May 3, 3:57 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 3, 7:32 PM CDT | Mesoscale Discussion | SPC | 58 min |
| May 10, 10:24 AM CDT | Mesoscale Discussion | SPC | 3 hr |
| May 10, 10:46 AM CDT | Tornado Watch | SPC | 8 hr |
| May 10, 2:43 PM CDT | Mesoscale Discussion | SPC | 92 min |
| May 14, 11:44 PM CDT | Dense Fog Advisory | OAX | 7 hr |
| May 16, 3:34 PM CDT | Mesoscale Discussion | SPC | 86 min |
| May 16, 5:26 PM CDT | Special Weather Statement | OAX | 49 min |
| May 25, 5:08 PM CDT | Mesoscale Discussion | SPC | 67 min |
| May 25, 5:33 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 25, 6:51 PM CDT | Special Weather Statement | OAX | 24 min |
| May 25, 8:18 PM CDT | Mesoscale Discussion | SPC | 87 min |
| May 29, 7:44 PM CDT | Special Weather Statement | OAX | 46 min |
| Jun 6, 3:53 PM CDT | Flash Flood Watch | OAX | 10 hr |
| Jun 6, 11:23 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 6, 11:51 PM CDT | Severe Thunderstorm Warning | OAX | 24 min |
| Jun 7, 12:19 AM CDT | Special Weather Statement | OAX | 41 min |
| Jun 10, 10:35 PM CDT | Flash Flood Watch | OAX | 13 hr |
| Jun 20, 12:48 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Jun 24, 12:39 AM CDT | Mesoscale Discussion | SPC | 66 min |
| Jun 24, 10:19 AM CDT | Mesoscale Discussion | SPC | 116 min |
| Jun 24, 6:21 PM CDT | Tornado Watch | SPC | 5 hr |
| Jun 24, 6:27 PM CDT | Severe Thunderstorm Warning | OAX | 63 min |
| Jun 24, 7:30 PM CDT | Special Weather Statement | OAX | 15 min |
| Jun 24, 10:28 PM CDT | Special Weather Statement | OAX | 17 min |
| Jul 11, 11:59 AM CDT | Heat Advisory | OAX | 32 hr |
| Jul 12, 3:32 PM CDT | Heat Advisory | OAX | 28 hr |
| Jul 16, 3:29 AM CDT | Special Weather Statement | OAX | 46 min |
| Jul 16, 6:44 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 17, 8:57 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 23, 3:07 PM CDT | Heat Advisory | OAX | 29 hr |
| Jul 24, 6:47 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jul 26, 2:49 AM CDT | Special Weather Statement | OAX | 26 min |
| Jul 28, 3:40 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 2, 4:04 AM CDT | Severe Thunderstorm Warning | OAX | 26 min |
| Aug 2, 4:26 AM CDT | Severe Thunderstorm Warning | OAX | 34 min |
| Aug 2, 4:30 AM CDT | Severe Thunderstorm Warning | OAX | 45 min |
| Aug 2, 4:48 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 9, 11:14 PM CDT | Special Weather Statement | OAX | 46 min |
| Aug 18, 8:28 AM CDT | Special Weather Statement | OAX | 47 min |
| Aug 22, 2:13 PM CDT | Mesoscale Discussion | SPC | 62 min |
| Aug 22, 2:55 PM CDT | Mesoscale Discussion | SPC | 65 min |
| Aug 22, 3:48 PM CDT | Tornado Watch | SPC | 8 hr |
| Aug 22, 6:21 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Sep 6, 4:24 AM CDT | Flash Flood Watch | OAX | 24 hr |
| Sep 6, 5:26 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Sep 6, 6:02 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Sep 6, 6:18 PM CDT | Special Weather Statement | OAX | 57 min |
| Sep 6, 6:30 PM CDT | Severe Thunderstorm Warning | OAX | 45 min |
| Sep 6, 8:42 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Sep 7, 4:19 AM CDT | Flash Flood Watch | OAX | 22 hr |
| Sep 22, 1:06 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Sep 22, 2:51 PM CDT | Special Weather Statement | OAX | 39 min |
| Sep 22, 3:20 PM CDT | Severe Thunderstorm Warning | OAX | 25 min |
| Sep 23, 4:31 AM CDT | Flash Flood Watch | OAX | 28 hr |
| Oct 15, 4:15 AM CDT | Frost Advisory | OAX | 29 hr |
| Oct 16, 3:11 PM CDT | Frost Advisory | OAX | 17 hr |
| Oct 19, 3:29 AM CDT | Red Flag Warning | OAX | 12 hr |
| Oct 23, 6:13 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Oct 23, 6:51 PM CDT | Special Weather Statement | OAX | 39 min |
| Nov 10, 3:28 AM CST | High Wind Watch | OAX | 24 hr |
| Nov 10, 3:25 PM CST | High Wind Warning | OAX | 32 hr |
| Nov 10, 3:25 PM CST | Wind Advisory | OAX | 36 hr |
| Nov 11, 10:17 AM CST | Mesoscale Discussion | SPC | 118 min |
| Nov 11, 11:25 AM CST | Tornado Watch | SPC | 6 hr |
| Nov 11, 12:23 PM CST | Special Weather Statement | OAX | 37 min |
| Nov 11, 1:42 PM CST | Mesoscale Discussion | SPC | 93 min |
| Nov 11, 1:54 PM CST | Tornado Warning | OAX | 18 min |
| Nov 11, 2:08 PM CST | Severe Thunderstorm Warning | OAX | 20 min |
| Nov 12, 2:55 AM CST | Wind Advisory | OAX | 13 hr |
| Nov 18, 3:39 PM CST | Wind Advisory | OAX | 25 hr |
| Nov 18, 3:39 PM CST | Winter Storm Watch | OAX | 37 hr |
| Nov 19, 3:27 PM CST | Winter Storm Warning | OAX | 27 hr |
| Nov 20, 9:00 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Nov 20, 1:51 PM CST | Mesoscale Discussion | SPC | 5 hr |
| Nov 24, 3:09 PM CST | Winter Storm Watch | OAX | 37 hr |
| Nov 25, 3:33 PM CST | Winter Storm Warning | OAX | 35 hr |
| Nov 25, 3:33 PM CST | Winter Weather Advisory | OAX | 35 hr |
| Nov 26, 7:04 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Nov 28, 2:59 PM CST | Winter Storm Watch | OAX | 25 hr |
| Nov 29, 3:34 PM CST | Winter Storm Warning | OAX | 29 hr |
| Nov 30, 6:44 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Dec 6, 8:12 PM CST | Dense Fog Advisory | OAX | 11 hr |
| Dec 24, 3:50 AM CST | Winter Weather Advisory | OAX | 10 hr |
| Dec 26, 3:20 PM CST | Winter Storm Watch | OAX | 24 hr |
| Dec 27, 3:33 PM CST | Winter Storm Warning | OAX | 34 hr |
| Dec 27, 3:33 PM CST | Winter Weather Advisory | OAX | 34 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 | 1 |
| Severe Thunderstorm Watch | 4 |
| Tornado Watch | 4 |
| Mesoscale Discussion | 30 |
| Special Weather Statement | 18 |
| Flooding | |
| Flash Flood Watch | 5 |
| Winter | |
| Winter Storm Warning | 5 |
| Winter Storm Watch | 4 |
| Freezing Rain Advisory | 1 |
| Winter Weather Advisory | 9 |
| Heat | |
| Heat Advisory | 3 |
| Cold | |
| Wind Chill Warning | 1 |
| Frost Advisory | 2 |
| Wind Chill Advisory | 4 |
| Wind and dust | |
| High Wind Warning | 1 |
| High Wind Watch | 1 |
| Wind Advisory | 7 |
| Fire | |
| Red Flag Warning | 6 |
| Fire Weather Watch | 3 |
| Fog and smoke | |
| Dense Fog Advisory | 3 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20142016
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.