Alert archive / Iowa / Sac County
Weather alerts in Sac County, Iowa, 2015
121 weather alerts in 2015, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Sac County and its neighbors
Each county as a circle sized by its count in 2015. Tap one for its archive.
- Alerts
- 121
- Warnings
- 27
- Watches
- 23
- Advisories
- 34
- Busiest month
- November19 alerts
- Busiest day
- June 24, 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.
Sac County, 2015
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 9 | 6 | 33% | 2 | 100% | 16 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 Des Moines, IA: tornado warnings | 38 | 14 | 63% | 37 | 62% | 13 min |
| NWS Des Moines, IA: severe thunderstorm warnings | 201 | 101 | 50% | 301 | 78% | 19 min |
| NWS Des Moines, IA: flash flood warnings | 39 | 22 | 44% | 86 | 86% | 121 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, 3:51 AM CST | Winter Weather Advisory | DMX | 26 hr |
| Jan 4, 4:00 AM CST | Winter Storm Watch | DMX | 24 hr |
| Jan 4, 6:07 AM CST | Wind Chill Advisory | DMX | 27 hr |
| Jan 4, 3:42 PM CST | Winter Storm Warning | DMX | 31 hr |
| Jan 5, 12:25 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Jan 5, 9:38 PM CST | Wind Chill Advisory | DMX | 14 hr |
| Jan 6, 4:15 AM CST | Wind Chill Warning | DMX | 32 hr |
| Jan 6, 4:15 AM CST | Wind Chill Advisory | DMX | 53 hr |
| Jan 7, 3:44 PM CST | Winter Weather Advisory | DMX | 38 hr |
| Jan 8, 2:05 PM CST | Blizzard Warning | DMX | 13 hr |
| Jan 9, 2:58 AM CST | Wind Chill Advisory | DMX | 30 hr |
| Jan 9, 5:38 AM CST | Wind Chill Advisory | DMX | 6 hr |
| Jan 17, 3:33 AM CST | Wind Advisory | DMX | 12 hr |
| Jan 28, 3:36 PM CST | Wind Advisory | DMX | 17 hr |
| Jan 31, 3:31 AM CST | Winter Storm Warning | DMX | 41 hr |
| Feb 1, 8:49 PM CST | Wind Chill Advisory | DMX | 12 hr |
| Feb 17, 3:51 AM CST | Wind Chill Advisory | DMX | 32 hr |
| Feb 24, 11:34 AM CST | Winter Storm Watch | DMX | 4 hr |
| Feb 24, 3:19 PM CST | Winter Storm Warning | DMX | 30 hr |
| Feb 24, 3:19 PM CST | Winter Weather Advisory | DMX | 30 hr |
| Feb 25, 9:01 PM CST | Wind Chill Advisory | DMX | 13 hr |
| Feb 26, 9:48 PM CST | Wind Chill Advisory | DMX | 11 hr |
| Mar 11, 4:32 PM CDT | Fire Weather Watch | DMX | 11 hr |
| Mar 12, 3:50 AM CDT | Red Flag Warning | DMX | 14 hr |
| Mar 14, 11:06 AM CDT | Fire Weather Watch | DMX | 17 hr |
| Mar 15, 3:41 AM CDT | Red Flag Warning | DMX | 15 hr |
| Mar 24, 4:03 AM CDT | Winter Weather Advisory | DMX | 21 hr |
| Mar 28, 3:44 PM CDT | Wind Advisory | DMX | 26 hr |
| Mar 30, 4:14 AM CDT | Red Flag Warning | DMX | 15 hr |
| Apr 1, 3:33 AM CDT | Wind Advisory | DMX | 14 hr |
| Apr 1, 3:46 AM CDT | Red Flag Warning | DMX | 15 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 4, 3:57 AM CDT | Red Flag Warning | DMX | 16 hr |
| Apr 12, 8:43 PM CDT | Special Weather Statement | DMX | 32 min |
| Apr 12, 9:11 PM CDT | Special Weather Statement | DMX | 34 min |
| Apr 20, 3:45 AM CDT | Wind Advisory | DMX | 15 hr |
| Apr 21, 3:39 AM CDT | Wind Advisory | DMX | 14 hr |
| Apr 22, 3:23 PM CDT | Freeze Warning | DMX | 17 hr |
| May 3, 3:57 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 3, 7:32 PM CDT | Mesoscale Discussion | SPC | 58 min |
| May 6, 12:07 AM CDT | Dense Fog Advisory | DMX | 9 hr |
| May 7, 6:11 PM CDT | Special Weather Statement | DMX | 34 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 10, 8:18 PM CDT | Severe Thunderstorm Warning | DMX | 27 min |
| May 15, 12:05 AM CDT | Dense Fog Advisory | DMX | 9 hr |
| May 17, 12:51 PM CDT | Mesoscale Discussion | SPC | 114 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, 7:10 PM CDT | Severe Thunderstorm Warning | DMX | 35 min |
| Jun 6, 3:37 PM CDT | Flash Flood Watch | DMX | 12 hr |
| Jun 6, 3:59 PM CDT | Special Weather Statement | DMX | 61 min |
| Jun 6, 11:00 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 6, 11:23 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 6, 11:54 PM CDT | Severe Thunderstorm Warning | DMX | 51 min |
| Jun 7, 12:26 AM CDT | Severe Thunderstorm Warning | DMX | 49 min |
| Jun 10, 2:12 PM CDT | Flash Flood Watch | DMX | 38 hr |
| Jun 20, 12:48 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Jun 22, 6:43 AM CDT | Severe Thunderstorm Warning | DMX | 47 min |
| Jun 22, 7:33 AM CDT | Wind Advisory | DMX | 2 hr |
| Jun 23, 3:59 PM CDT | Flash Flood Watch | DMX | 38 hr |
| Jun 24, 12:39 AM CDT | Mesoscale Discussion | SPC | 66 min |
| Jun 24, 3:29 AM CDT | Severe Thunderstorm Warning | DMX | 31 min |
| Jun 24, 12:29 PM CDT | Special Weather Statement | DMX | 61 min |
| Jun 24, 12:36 PM CDT | Severe Thunderstorm Warning | DMX | 54 min |
| Jun 24, 5:58 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 24, 6:21 PM CDT | Tornado Watch | SPC | 5 hr |
| Jul 11, 3:19 PM CDT | Heat Advisory | DMX | 28 hr |
| Jul 12, 5:28 PM CDT | Tornado Watch | SPC | 5 hr |
| Jul 16, 6:44 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 17, 8:57 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 17, 11:26 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 23, 3:55 PM CDT | Heat Advisory | DMX | 28 hr |
| Jul 24, 6:47 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jul 26, 1:13 AM CDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 9, 7:15 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 9, 9:33 PM CDT | Mesoscale Discussion | SPC | 27 min |
| Aug 16, 4:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Aug 18, 4:06 AM CDT | Flash Flood Watch | DMX | 9 hr |
| Aug 22, 2:13 PM CDT | Mesoscale Discussion | SPC | 62 min |
| Aug 22, 2:35 PM CDT | Tornado Watch | SPC | 7 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, 8:42 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Sep 7, 4:21 AM CDT | Flash Flood Watch | DMX | 30 hr |
| Sep 17, 4:06 AM CDT | Special Weather Statement | DMX | 39 min |
| Oct 11, 3:59 PM CDT | Wind Advisory | DMX | 26 hr |
| Oct 15, 4:01 AM CDT | Frost Advisory | DMX | 29 hr |
| Oct 15, 5:34 AM CDT | Red Flag Warning | DMX | 13 hr |
| Oct 16, 3:54 AM CDT | Frost Advisory | DMX | 29 hr |
| Oct 18, 2:56 PM CDT | Red Flag Warning | DMX | 28 hr |
| Oct 23, 6:13 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Nov 10, 3:20 AM CST | High Wind Watch | DMX | 24 hr |
| Nov 10, 3:39 PM CST | High Wind Warning | DMX | 38 hr |
| Nov 10, 3:39 PM CST | Wind Advisory | DMX | 50 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, 1:07 PM CST | Severe Thunderstorm Warning | DMX | 23 min |
| Nov 11, 2:54 PM CST | Severe Thunderstorm Warning | DMX | 51 min |
| Nov 18, 3:12 PM CST | Wind Advisory | DMX | 27 hr |
| Nov 18, 4:05 PM CST | Winter Storm Watch | DMX | 36 hr |
| Nov 19, 3:41 PM CST | Winter Storm Warning | DMX | 38 hr |
| Nov 20, 9:00 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Nov 20, 1:51 PM CST | Mesoscale Discussion | SPC | 5 hr |
| Nov 25, 3:52 AM CST | Winter Storm Watch | DMX | 24 hr |
| Nov 25, 4:39 PM CST | Winter Weather Advisory | DMX | 34 hr |
| Nov 26, 7:04 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Nov 28, 3:55 PM CST | Winter Storm Watch | DMX | 24 hr |
| Nov 29, 3:46 PM CST | Winter Storm Warning | DMX | 36 hr |
| Nov 30, 6:44 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Nov 30, 12:03 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Dec 6, 8:12 PM CST | Dense Fog Advisory | DMX | 15 hr |
| Dec 14, 7:25 AM CST | Wind Advisory | DMX | 5 hr |
| Dec 14, 11:06 AM CST | Areal Flood Warning | DMX | 24 hr |
| Dec 24, 3:27 AM CST | Winter Weather Advisory | DMX | 15 hr |
| Dec 25, 9:10 AM CST | Dense Fog Advisory | DMX | 6 hr |
| Dec 26, 3:46 PM CST | Winter Storm Watch | DMX | 23 hr |
| Dec 27, 4:46 AM CST | Winter Storm Warning | DMX | 49 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 | 9 |
| Severe Thunderstorm Watch | 4 |
| Tornado Watch | 5 |
| Mesoscale Discussion | 31 |
| Special Weather Statement | 6 |
| Flooding | |
| Areal Flood Warning | 1 |
| Flash Flood Watch | 5 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Warning | 6 |
| Winter Storm Watch | 6 |
| Winter Weather Advisory | 6 |
| Heat | |
| Heat Advisory | 2 |
| Cold | |
| Freeze Warning | 1 |
| Wind Chill Warning | 1 |
| Frost Advisory | 2 |
| Wind Chill Advisory | 9 |
| Wind and dust | |
| High Wind Warning | 1 |
| High Wind Watch | 1 |
| Wind Advisory | 11 |
| Fire | |
| Red Flag Warning | 7 |
| Fire Weather Watch | 2 |
| 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 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.