Alert archive / Iowa / Shelby County
Weather alerts in Shelby County, Iowa, 2019
131 weather alerts in 2019, 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 2019. Tap one for its archive.
- Alerts
- 131
- Warnings
- 29
- Watches
- 21
- Advisories
- 40
- Busiest month
- July20 alerts
- Busiest day
- July 17, 20196 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 Shelby County in 2019 had a tornado report inside them.
Shelby County, 2019
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 2 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 14 | 8 | 43% | 17 | 71% | 11 min |
| Flash flood warnings | 1 | 0 | 100% | 0 |
Each office's whole area, 2019
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Omaha, NE: tornado warnings | 23 | 7 | 70% | 9 | 78% | 18 min |
| NWS Omaha, NE: severe thunderstorm warnings | 191 | 82 | 57% | 179 | 74% | 17 min |
| NWS Omaha, NE: flash flood warnings | 47 | 10 | 79% | 27 | 81% | 284 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 7, 2:53 PM CST | Wind Advisory | OAX | 25 hr |
| Jan 10, 3:32 PM CST | Winter Weather Advisory | OAX | 48 hr |
| Jan 14, 9:13 PM CST | Dense Fog Advisory | OAX | 12 hr |
| Jan 17, 3:38 AM CST | Winter Weather Advisory | OAX | 48 hr |
| Jan 17, 2:49 PM CST | Winter Storm Warning | OAX | 31 hr |
| Jan 21, 3:47 AM CST | Winter Weather Advisory | OAX | 50 hr |
| Jan 23, 3:01 PM CST | Winter Weather Advisory | OAX | 27 hr |
| Jan 23, 3:32 PM CST | Wind Chill Advisory | OAX | 41 hr |
| Jan 27, 3:55 AM CST | Wind Advisory | OAX | 38 hr |
| Jan 27, 3:18 PM CST | Wind Chill Watch | OAX | 36 hr |
| Jan 28, 2:38 AM CST | Wind Chill Warning | OAX | 57 hr |
| Jan 28, 2:38 AM CST | Wind Chill Advisory | OAX | 3 days |
| Jan 29, 3:19 AM CST | Wind Chill Advisory | OAX | 54 hr |
| Feb 2, 12:14 PM CST | Dense Fog Advisory | OAX | 25 hr |
| Feb 5, 7:49 AM CST | Special Weather Statement | OAX | 86 min |
| Feb 5, 3:31 PM CST | Winter Weather Advisory | OAX | 50 hr |
| Feb 7, 3:29 AM CST | Wind Chill Advisory | OAX | 33 hr |
| Feb 10, 2:55 AM CST | Winter Weather Advisory | OAX | 9 hr |
| Feb 10, 3:56 AM CST | Winter Weather Advisory | OAX | 44 hr |
| Feb 15, 3:35 PM CST | Winter Weather Advisory | OAX | 50 hr |
| Feb 16, 7:26 PM CST | Mesoscale Discussion | SPC | 5 hr |
| Feb 16, 9:51 PM CST | Winter Storm Warning | OAX | 6 hr |
| Feb 18, 3:50 AM CST | Winter Storm Watch | OAX | 24 hr |
| Feb 19, 3:40 AM CST | Winter Storm Warning | OAX | 32 hr |
| Feb 21, 4:18 AM CST | Winter Weather Advisory | OAX | 71 hr |
| Feb 21, 4:13 PM CST | Winter Storm Watch | OAX | 22 hr |
| Feb 22, 1:46 PM CST | Blizzard Warning | OAX | 37 hr |
| Feb 23, 5:26 PM CST | Mesoscale Discussion | SPC | 5 hr |
| Feb 24, 5:02 AM CST | Winter Weather Advisory | OAX | 10 hr |
| Mar 2, 3:22 AM CST | Wind Chill Advisory | OAX | 57 hr |
| Mar 2, 3:38 PM CST | Wind Chill Advisory | OAX | 44 hr |
| Mar 6, 3:21 AM CST | Winter Weather Advisory | OAX | 36 hr |
| Mar 9, 3:27 AM CST | Wind Advisory | OAX | 21 hr |
| Mar 11, 3:31 AM CDT | Flood Watch | OAX | 3 days |
| Mar 12, 1:48 PM CDT | Areal Flood Advisory | OAX | 6 hr |
| Mar 12, 3:13 PM CDT | Dense Fog Advisory | OAX | 25 hr |
| Mar 13, 6:34 AM CDT | Areal Flood Warning | OAX | 12 hr |
| Mar 13, 9:41 AM CDT | Areal Flood Warning | OAX | 3 hr |
| Mar 13, 12:41 PM CDT | Flash Flood Warning | OAX | 6 hr |
| Mar 13, 4:02 PM CDT | Wind Advisory | OAX | 33 hr |
| Mar 13, 6:29 PM CDT | Areal Flood Warning | OAX | 39 hr |
| Mar 15, 9:45 AM CDT | Areal Flood Warning | OAX | 24 hr |
| Apr 5, 1:05 AM CDT | Dense Fog Advisory | OAX | 9 hr |
| Apr 10, 4:06 AM CDT | Wind Advisory | OAX | 30 hr |
| Apr 27, 3:24 AM CDT | Frost Advisory | OAX | 24 hr |
| Apr 27, 4:00 PM CDT | Freeze Warning | OAX | 11 hr |
| May 5, 1:35 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 5, 3:39 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 16, 7:57 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 16, 9:22 PM CDT | Severe Thunderstorm Warning | OAX | 23 min |
| May 16, 11:12 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 18, 4:36 AM CDT | Flash Flood Watch | OAX | 20 hr |
| May 21, 12:39 PM CDT | Special Weather Statement | OAX | 81 min |
| May 26, 1:17 PM CDT | Flash Flood Watch | OAX | 25 hr |
| May 27, 10:55 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 28, 4:55 AM CDT | Severe Thunderstorm Warning | OAX | 17 min |
| May 28, 4:58 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 15, 12:30 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 21, 2:07 AM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 21, 2:39 AM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 21, 4:34 AM CDT | Mesoscale Discussion | SPC | 86 min |
| Jun 25, 2:19 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 25, 1:58 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Jun 25, 3:08 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 26, 1:55 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 28, 3:01 PM CDT | Heat Advisory | OAX | 30 hr |
| Jun 29, 2:55 AM CDT | Heat Advisory | OAX | 41 hr |
| Jul 2, 3:42 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Jul 2, 3:49 PM CDT | Special Weather Statement | OAX | 26 min |
| Jul 2, 4:17 PM CDT | Severe Thunderstorm Warning | OAX | 43 min |
| Jul 3, 2:33 AM CDT | Special Weather Statement | OAX | 42 min |
| Jul 3, 3:37 AM CDT | Areal Flood Advisory | OAX | 113 min |
| Jul 3, 2:00 PM CDT | Special Weather Statement | OAX | 30 min |
| Jul 3, 2:41 PM CDT | Severe Thunderstorm Warning | OAX | 19 min |
| Jul 15, 3:48 PM CDT | Excessive Heat Watch | OAX | 5 hr |
| Jul 15, 3:48 PM CDT | Excessive Heat Watch | OAX | 5 hr |
| Jul 15, 3:48 PM CDT | Excessive Heat Watch | OAX | 36 hr |
| Jul 16, 3:56 PM CDT | Excessive Heat Warning | OAX | 4 days |
| Jul 17, 9:09 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Jul 17, 9:35 AM CDT | Special Weather Statement | OAX | 25 min |
| Jul 17, 9:47 AM CDT | Special Weather Statement | OAX | 13 min |
| Jul 17, 9:51 AM CDT | Severe Thunderstorm Warning | OAX | 39 min |
| Jul 17, 10:29 AM CDT | Severe Thunderstorm Warning | OAX | 16 min |
| Jul 17, 10:35 AM CDT | Severe Thunderstorm Warning | OAX | 10 min |
| Jul 20, 4:40 PM CDT | Mesoscale Discussion | SPC | 95 min |
| Jul 20, 5:14 PM CDT | Special Weather Statement | OAX | 16 min |
| Jul 20, 11:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Aug 11, 2:47 PM CDT | Flash Flood Watch | OAX | 14 hr |
| Aug 12, 3:57 AM CDT | Special Weather Statement | OAX | 63 min |
| Aug 18, 12:00 AM CDT | Mesoscale Discussion | SPC | 90 min |
| Aug 18, 4:26 AM CDT | Special Weather Statement | OAX | 34 min |
| Aug 18, 4:59 AM CDT | Special Weather Statement | OAX | 31 min |
| Aug 19, 11:05 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Aug 19, 11:56 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 20, 2:40 AM CDT | Severe Thunderstorm Warning | OAX | 20 min |
| Aug 20, 2:55 AM CDT | Severe Thunderstorm Warning | OAX | 20 min |
| Aug 20, 3:03 AM CDT | Tornado Warning | OAX | 15 min |
| Aug 20, 3:08 AM CDT | Mesoscale Discussion | SPC | 97 min |
| Aug 29, 3:32 AM CDT | Special Weather Statement | OAX | 28 min |
| Aug 29, 3:52 AM CDT | Special Weather Statement | OAX | 23 min |
| Sep 2, 3:06 AM CDT | Dense Fog Advisory | OAX | 5 hr |
| Sep 9, 2:49 PM CDT | Mesoscale Discussion | SPC | 116 min |
| Sep 14, 11:54 AM CDT | Special Weather Statement | OAX | 21 min |
| Sep 14, 11:37 PM CDT | Special Weather Statement | OAX | 38 min |
| Sep 15, 12:11 AM CDT | Severe Thunderstorm Warning | OAX | 18 min |
| Sep 18, 4:04 PM CDT | Flood Watch | OAX | 21 hr |
| Sep 18, 10:28 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 21, 7:54 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 24, 4:43 PM CDT | Tornado Watch | SPC | 7 hr |
| Sep 24, 6:14 PM CDT | Tornado Warning | OAX | 33 min |
| Sep 24, 6:33 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Sep 24, 7:01 PM CDT | Severe Thunderstorm Warning | OAX | 29 min |
| Sep 24, 7:17 PM CDT | Special Weather Statement | OAX | 28 min |
| Sep 24, 7:35 PM CDT | Severe Thunderstorm Warning | OAX | 25 min |
| Sep 24, 7:59 PM CDT | Severe Thunderstorm Warning | OAX | 31 min |
| Sep 24, 8:08 PM CDT | Severe Thunderstorm Warning | OAX | 10 min |
| Sep 30, 3:58 AM CDT | Flash Flood Watch | OAX | 41 hr |
| Oct 1, 8:35 PM CDT | Flood Watch | OAX | 9 hr |
| Oct 10, 3:37 AM CDT | Freeze Watch | OAX | 25 hr |
| Oct 11, 4:12 AM CDT | Freeze Warning | OAX | 30 hr |
| Oct 18, 3:47 AM CDT | Wind Advisory | OAX | 14 hr |
| Oct 21, 3:42 AM CDT | Wind Advisory | OAX | 30 hr |
| Nov 10, 2:34 PM CST | Winter Weather Advisory | OAX | 18 hr |
| Nov 13, 3:32 AM CST | Winter Weather Advisory | OAX | 9 hr |
| Nov 25, 3:32 PM CST | Winter Weather Advisory | OAX | 41 hr |
| Nov 27, 4:07 PM CST | Winter Weather Advisory | OAX | 47 hr |
| Nov 30, 3:20 AM CST | Wind Advisory | OAX | 33 hr |
| Dec 9, 7:50 AM CST | Special Weather Statement | OAX | 85 min |
| Dec 9, 8:43 AM CST | Special Weather Statement | OAX | 92 min |
| Dec 13, 6:38 AM CST | Special Weather Statement | OAX | 112 min |
| Dec 16, 11:29 PM CST | Dense Fog Advisory | OAX | 10 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 archive20182020
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.