Alert archive / South Dakota / Dewey County
Weather alerts in Dewey County, South Dakota, 2018
154 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Dewey County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 154
- Warnings
- 54
- Watches
- 15
- Advisories
- 40
- Busiest month
- June44 alerts
- Busiest day
- July 4, 20189 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 Dewey County in 2018 had a tornado report inside them.
Dewey County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 42 | 30 | 29% | 25 | 80% | 16 min |
| Flash flood warnings | 2 | 2 | 0% | 0 |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Aberdeen, SD: tornado warnings | 7 | 2 | 71% | 9 | 33% | 8 min |
| NWS Aberdeen, SD: severe thunderstorm warnings | 233 | 158 | 32% | 290 | 82% | 17 min |
| NWS Aberdeen, SD: flash flood warnings | 12 | 11 | 8% | 16 | 69% | 142 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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jan 1, 10:55 AM MST | Wind Chill Advisory | ABR | 22 hr |
| Jan 9, 3:18 AM MST | Winter Weather Advisory | ABR | 50 hr |
| Jan 10, 11:34 PM MST | Wind Chill Advisory | ABR | 34 hr |
| Jan 14, 2:25 AM MST | Wind Chill Warning | ABR | 56 hr |
| Jan 14, 2:25 AM MST | Wind Chill Advisory | ABR | 56 hr |
| Jan 22, 1:04 AM MST | Dense Fog Advisory | ABR | 13 hr |
| Jan 22, 2:20 PM MST | Dense Fog Advisory | ABR | 18 hr |
| Feb 3, 2:19 AM MST | Wind Chill Advisory | ABR | 33 hr |
| Feb 7, 2:01 PM MST | Winter Weather Advisory | ABR | 33 hr |
| Feb 9, 2:12 PM MST | Wind Chill Advisory | ABR | 19 hr |
| Feb 17, 2:08 PM MST | Winter Storm Watch | ABR | 20 hr |
| Feb 18, 10:15 AM MST | Winter Storm Warning | ABR | 43 hr |
| Feb 20, 1:53 PM MST | Wind Chill Advisory | ABR | 19 hr |
| Feb 28, 1:07 AM MST | Dense Fog Advisory | ABR | 8 hr |
| Mar 2, 1:58 PM MST | Winter Storm Watch | ABR | 47 hr |
| Mar 3, 1:07 PM MST | Dense Fog Advisory | ABR | 22 hr |
| Mar 4, 3:40 AM MST | Blizzard Warning | ABR | 55 hr |
| Mar 10, 8:01 AM MST | Winter Weather Advisory | ABR | 3 hr |
| Mar 15, 2:46 AM MDT | Winter Weather Advisory | ABR | 45 hr |
| Mar 16, 6:14 PM MDT | Winter Weather Advisory | ABR | 6 hr |
| Mar 22, 4:50 AM MDT | Dense Fog Advisory | ABR | 8 hr |
| Mar 25, 2:32 PM MDT | Winter Weather Advisory | ABR | 23 hr |
| Mar 30, 12:15 PM MDT | Wind Advisory | ABR | 21 hr |
| Apr 2, 3:12 AM MDT | Winter Weather Advisory | ABR | 36 hr |
| Apr 6, 2:34 PM MDT | Winter Weather Advisory | ABR | 53 hr |
| Apr 10, 1:36 PM MDT | Winter Storm Watch | ABR | 49 hr |
| Apr 12, 10:48 AM MDT | Blizzard Warning | ABR | 55 hr |
| Apr 17, 1:27 AM MDT | Winter Weather Advisory | ABR | 24 hr |
| Apr 29, 2:52 AM MDT | Wind Advisory | ABR | 16 hr |
| May 7, 6:17 PM MDT | Mesoscale Discussion | SPC | 118 min |
| May 7, 7:21 PM MDT | Special Weather Statement | ABR | 54 min |
| May 17, 1:23 PM MDT | Severe Thunderstorm Watch | SPC | 10 hr |
| May 17, 2:47 PM MDT | Mesoscale Discussion | SPC | 28 min |
| May 17, 4:54 PM MDT | Mesoscale Discussion | SPC | 66 min |
| May 17, 5:24 PM MDT | Severe Thunderstorm Warning | ABR | 51 min |
| May 17, 5:32 PM MDT | Severe Thunderstorm Warning | ABR | 43 min |
| May 17, 6:20 PM MDT | Severe Thunderstorm Warning | ABR | 55 min |
| May 17, 6:45 PM MDT | Severe Thunderstorm Warning | ABR | 45 min |
| May 17, 7:08 PM MDT | Severe Thunderstorm Warning | ABR | 52 min |
| May 17, 7:11 PM MDT | Mesoscale Discussion | SPC | 64 min |
| May 17, 7:58 PM MDT | Severe Thunderstorm Warning | ABR | 47 min |
| May 17, 9:11 PM MDT | Severe Thunderstorm Warning | ABR | 49 min |
| May 19, 2:46 PM MDT | Frost Advisory | ABR | 15 hr |
| May 22, 4:56 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| May 23, 1:36 AM MDT | Special Weather Statement | ABR | 39 min |
| May 23, 2:09 AM MDT | Special Weather Statement | ABR | 51 min |
| May 23, 10:12 PM MDT | Special Weather Statement | ABR | 48 min |
| May 27, 5:06 PM MDT | Mesoscale Discussion | SPC | 84 min |
| May 27, 5:27 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 1, 1:13 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 1, 1:53 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 1, 4:04 PM MDT | Severe Thunderstorm Warning | ABR | 41 min |
| Jun 1, 4:44 PM MDT | Severe Thunderstorm Warning | ABR | 46 min |
| Jun 1, 5:31 PM MDT | Special Weather Statement | ABR | 59 min |
| Jun 1, 5:32 PM MDT | Mesoscale Discussion | SPC | 88 min |
| Jun 1, 6:00 PM MDT | Severe Thunderstorm Warning | ABR | 60 min |
| Jun 1, 6:23 PM MDT | Severe Thunderstorm Warning | ABR | 67 min |
| Jun 2, 1:56 AM MDT | Wind Advisory | ABR | 16 hr |
| Jun 5, 8:07 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 5, 9:04 PM MDT | Severe Thunderstorm Warning | ABR | 41 min |
| Jun 5, 9:11 PM MDT | Severe Thunderstorm Warning | ABR | 49 min |
| Jun 5, 9:54 PM MDT | Severe Thunderstorm Warning | ABR | 51 min |
| Jun 5, 10:21 PM MDT | Severe Thunderstorm Warning | ABR | 39 min |
| Jun 5, 10:30 PM MDT | Severe Thunderstorm Warning | ABR | 45 min |
| Jun 8, 12:43 AM MDT | Special Weather Statement | ABR | 47 min |
| Jun 10, 1:15 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 10, 2:52 PM MDT | Tornado Watch | SPC | 7 hr |
| Jun 10, 5:36 PM MDT | Mesoscale Discussion | SPC | 114 min |
| Jun 10, 7:52 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jun 10, 10:39 PM MDT | Special Weather Statement | ABR | 36 min |
| Jun 10, 11:09 PM MDT | Severe Thunderstorm Warning | ABR | 12 min |
| Jun 14, 2:40 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 14, 5:15 PM MDT | Mesoscale Discussion | SPC | 90 min |
| Jun 14, 6:29 PM MDT | Special Weather Statement | ABR | 31 min |
| Jun 14, 8:45 PM MDT | Special Weather Statement | ABR | 30 min |
| Jun 14, 9:49 PM MDT | Severe Thunderstorm Warning | ABR | 26 min |
| Jun 16, 7:24 AM MDT | Severe Thunderstorm Warning | ABR | 51 min |
| Jun 16, 7:53 AM MDT | Severe Thunderstorm Warning | ABR | 52 min |
| Jun 16, 8:13 AM MDT | Mesoscale Discussion | SPC | 92 min |
| Jun 16, 5:14 PM MDT | Mesoscale Discussion | SPC | 91 min |
| Jun 16, 6:59 PM MDT | Mesoscale Discussion | SPC | 91 min |
| Jun 16, 8:50 PM MDT | Mesoscale Discussion | SPC | 85 min |
| Jun 26, 10:52 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jun 26, 11:12 PM MDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 27, 12:18 AM MDT | Severe Thunderstorm Warning | ABR | 42 min |
| Jun 27, 12:58 AM MDT | Severe Thunderstorm Warning | ABR | 47 min |
| Jun 27, 1:18 AM MDT | Mesoscale Discussion | SPC | 87 min |
| Jun 27, 1:42 AM MDT | Severe Thunderstorm Warning | ABR | 48 min |
| Jun 27, 2:28 AM MDT | Severe Thunderstorm Warning | ABR | 47 min |
| Jun 29, 4:57 PM MDT | Mesoscale Discussion | SPC | 63 min |
| Jun 29, 5:19 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 29, 7:17 PM MDT | Severe Thunderstorm Warning | ABR | 43 min |
| Jun 29, 7:52 PM MDT | Severe Thunderstorm Warning | ABR | 53 min |
| Jul 2, 4:23 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 3, 9:38 PM MDT | Mesoscale Discussion | SPC | 97 min |
| Jul 3, 10:02 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 3, 11:48 PM MDT | Severe Thunderstorm Warning | ABR | 42 min |
| Jul 3, 11:58 PM MDT | Tornado Warning | ABR | 21 min |
| Jul 4, 12:07 AM MDT | Severe Thunderstorm Warning | ABR | 38 min |
| Jul 4, 12:13 AM MDT | Severe Thunderstorm Warning | ABR | 47 min |
| Jul 4, 12:31 AM MDT | Severe Thunderstorm Warning | ABR | 29 min |
| Jul 4, 12:42 AM MDT | Severe Thunderstorm Warning | ABR | 48 min |
| Jul 4, 12:58 AM MDT | Severe Thunderstorm Warning | ABR | 47 min |
| Jul 6, 1:53 PM MDT | Heat Advisory | ABR | 29 hr |
| Jul 7, 2:08 AM MDT | Heat Advisory | ABR | 41 hr |
| Jul 14, 8:50 PM MDT | Special Weather Statement | ABR | 40 min |
| Jul 18, 9:32 AM MDT | Areal Flood Warning | ABR | 3 hr |
| Jul 18, 2:43 PM MDT | Tornado Watch | SPC | 7 hr |
| Jul 18, 2:51 PM MDT | Special Weather Statement | ABR | 39 min |
| Jul 18, 4:16 PM MDT | Mesoscale Discussion | SPC | 119 min |
| Jul 18, 4:45 PM MDT | Special Weather Statement | ABR | 60 min |
| Jul 18, 5:48 PM MDT | Special Weather Statement | ABR | 42 min |
| Jul 18, 6:00 PM MDT | Special Weather Statement | ABR | 30 min |
| Jul 19, 2:43 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 19, 7:42 PM MDT | Severe Thunderstorm Warning | ABR | 48 min |
| Jul 19, 8:27 PM MDT | Severe Thunderstorm Warning | ABR | 41 min |
| Jul 22, 12:02 AM MDT | Flash Flood Warning | ABR | 6 hr |
| Jul 22, 1:51 AM MDT | Flash Flood Warning | ABR | 6 hr |
| Jul 22, 4:53 AM MDT | Areal Flood Warning | ABR | 6 hr |
| Jul 22, 12:55 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 3, 11:06 PM MDT | Severe Thunderstorm Warning | ABR | 39 min |
| Aug 4, 2:42 PM MDT | Mesoscale Discussion | SPC | 93 min |
| Aug 18, 1:45 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 23, 7:37 PM MDT | Severe Thunderstorm Warning | ABR | 23 min |
| Aug 26, 4:19 AM MDT | Severe Thunderstorm Warning | ABR | 56 min |
| Aug 26, 5:15 AM MDT | Severe Thunderstorm Warning | ABR | 45 min |
| Aug 26, 5:15 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 26, 6:18 PM MDT | Severe Thunderstorm Warning | ABR | 42 min |
| Sep 1, 11:22 PM MDT | Special Weather Statement | ABR | 38 min |
| Sep 1, 11:43 PM MDT | Severe Thunderstorm Warning | ABR | 24 min |
| Sep 1, 11:51 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 9, 9:29 PM MDT | Severe Thunderstorm Warning | ABR | 46 min |
| Sep 19, 1:12 AM MDT | Special Weather Statement | ABR | 48 min |
| Sep 19, 1:30 AM MDT | Severe Thunderstorm Warning | ABR | 60 min |
| Sep 19, 2:47 AM MDT | Mesoscale Discussion | SPC | 3 hr |
| Sep 23, 4:51 AM MDT | Dense Fog Advisory | ABR | 6 hr |
| Sep 25, 8:57 AM MDT | Wind Advisory | ABR | 9 hr |
| Sep 27, 2:14 PM MDT | Frost Advisory | ABR | 18 hr |
| Oct 3, 2:24 AM MDT | Freeze Watch | ABR | 11 hr |
| Oct 3, 2:24 AM MDT | Wind Advisory | ABR | 18 hr |
| Oct 3, 1:51 PM MDT | Freeze Warning | ABR | 18 hr |
| Oct 9, 3:51 AM MDT | Winter Weather Advisory | ABR | 38 hr |
| Oct 27, 2:42 AM MDT | Wind Advisory | ABR | 16 hr |
| Nov 6, 2:13 AM MST | Wind Advisory | ABR | 14 hr |
| Nov 15, 2:08 PM MST | Winter Weather Advisory | ABR | 33 hr |
| Nov 22, 12:39 AM MST | Dense Fog Advisory | ABR | 10 hr |
| Nov 27, 2:22 PM MST | Winter Weather Advisory | ABR | 27 hr |
| Nov 29, 7:25 PM MST | Dense Fog Advisory | ABR | 16 hr |
| Dec 18, 1:36 PM MST | Wind Advisory | ABR | 27 hr |
| Dec 25, 2:45 AM MST | Winter Storm Watch | ABR | 11 hr |
| Dec 25, 1:28 PM MST | Winter Storm Warning | ABR | 37 hr |
| Dec 27, 2:57 AM MST | Winter Storm Warning | ABR | 11 hr |
| Dec 27, 1:48 PM MST | Winter Weather Advisory | ABR | 13 hr |
| Dec 30, 1:36 PM MST | Winter Weather Advisory | ABR | 27 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 | 42 |
| Tornado Warning | 1 |
| Severe Thunderstorm Watch | 8 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 29 |
| Special Weather Statement | 16 |
| Flooding | |
| Areal Flood Warning | 2 |
| Flash Flood Warning | 2 |
| Winter | |
| Blizzard Warning | 2 |
| Winter Storm Warning | 3 |
| Winter Storm Watch | 4 |
| Winter Weather Advisory | 14 |
| Heat | |
| Heat Advisory | 2 |
| Cold | |
| Freeze Warning | 1 |
| Wind Chill Warning | 1 |
| Freeze Watch | 1 |
| Frost Advisory | 2 |
| Wind Chill Advisory | 6 |
| Wind and dust | |
| Wind Advisory | 8 |
| Fog and smoke | |
| Dense Fog Advisory | 8 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20172019
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.