Alert archive / South Dakota / Dewey County
Weather alerts in Dewey County, South Dakota, 2017
94 weather alerts in 2017, 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 2017. Tap one for its archive.
- Alerts
- 94
- Warnings
- 25
- Watches
- 7
- Advisories
- 34
- Busiest month
- August19 alerts
- Busiest day
- July 21, 20177 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Dewey County, 2017
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 18 | 13 | 28% | 5 | 80% | 9 min |
| Flash flood warnings | 0 | 1 | 0% |
Each office's whole area, 2017
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Aberdeen, SD: tornado warnings | 19 | 7 | 63% | 16 | 63% | 15 min |
| NWS Aberdeen, SD: severe thunderstorm warnings | 201 | 138 | 31% | 306 | 81% | 20 min |
| NWS Aberdeen, SD: flash flood warnings | 2 | 1 | 50% | 5 | 20% | 64 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, 2:54 AM MST | Winter Weather Advisory | ABR | 50 hr |
| Jan 3, 4:53 AM MST | Wind Chill Advisory | ABR | 12 hr |
| Jan 3, 2:12 PM MST | Wind Chill Warning | ABR | 21 hr |
| Jan 3, 2:12 PM MST | Wind Chill Advisory | ABR | 64 hr |
| Jan 8, 12:38 PM MST | Winter Weather Advisory | ABR | 6 hr |
| Jan 9, 2:12 PM MST | Winter Weather Advisory | ABR | 26 hr |
| Jan 11, 1:55 PM MST | Wind Chill Advisory | ABR | 19 hr |
| Jan 12, 1:58 AM MST | Winter Weather Advisory | ABR | 12 hr |
| Jan 12, 2:07 PM MST | Wind Chill Advisory | ABR | 16 hr |
| Jan 19, 2:05 PM MST | Dense Fog Advisory | ABR | 21 hr |
| Jan 23, 12:50 PM MST | Winter Weather Advisory | ABR | 14 hr |
| Jan 24, 2:28 AM MST | Winter Weather Advisory | ABR | 27 hr |
| Jan 27, 9:58 AM MST | Winter Weather Advisory | ABR | 7 hr |
| Jan 30, 1:48 AM MST | High Wind Warning | ABR | 13 hr |
| Jan 30, 1:48 AM MST | Wind Advisory | ABR | 15 hr |
| Mar 5, 3:06 AM MST | High Wind Watch | ABR | 11 hr |
| Mar 5, 2:25 PM MST | High Wind Watch | ABR | 36 hr |
| Mar 5, 2:25 PM MST | High Wind Warning | ABR | 54 hr |
| Mar 10, 2:32 AM MST | Winter Weather Advisory | ABR | 18 hr |
| Mar 11, 1:36 PM MST | Winter Weather Advisory | ABR | 33 hr |
| Apr 17, 7:27 PM MDT | Special Weather Statement | ABR | 33 min |
| Apr 17, 9:24 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| May 23, 1:57 PM MDT | Frost Advisory | ABR | 16 hr |
| May 27, 6:56 PM MDT | Special Weather Statement | ABR | 49 min |
| May 28, 1:52 PM MDT | Special Weather Statement | ABR | 38 min |
| May 28, 2:54 PM MDT | Mesoscale Discussion | SPC | 66 min |
| May 29, 1:18 PM MDT | Frost Advisory | ABR | 17 hr |
| Jun 2, 1:48 PM MDT | Mesoscale Discussion | SPC | 87 min |
| Jun 10, 8:44 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 10, 9:01 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 10, 10:56 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 12, 10:14 PM MDT | Mesoscale Discussion | SPC | 91 min |
| Jun 12, 10:28 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 27, 6:02 PM MDT | Mesoscale Discussion | SPC | 88 min |
| Jun 27, 7:29 PM MDT | Severe Thunderstorm Warning | ABR | 46 min |
| Jul 4, 4:11 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 5, 4:52 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 5, 5:16 PM MDT | Severe Thunderstorm Warning | ABR | 44 min |
| Jul 5, 6:54 PM MDT | Severe Thunderstorm Warning | ABR | 51 min |
| Jul 5, 7:20 PM MDT | Severe Thunderstorm Warning | ABR | 40 min |
| Jul 19, 6:01 AM MDT | Mesoscale Discussion | SPC | 119 min |
| Jul 19, 6:29 AM MDT | Severe Thunderstorm Warning | ABR | 46 min |
| Jul 19, 8:17 AM MDT | Severe Thunderstorm Warning | ABR | 43 min |
| Jul 20, 6:31 PM MDT | Mesoscale Discussion | SPC | 89 min |
| Jul 20, 7:32 PM MDT | Severe Thunderstorm Warning | ABR | 43 min |
| Jul 20, 8:13 PM MDT | Severe Thunderstorm Warning | ABR | 62 min |
| Jul 20, 8:45 PM MDT | Severe Thunderstorm Warning | ABR | 60 min |
| Jul 20, 9:41 PM MDT | Severe Thunderstorm Warning | ABR | 64 min |
| Jul 21, 2:07 PM MDT | Severe Thunderstorm Watch | SPC | 10 hr |
| Jul 21, 2:53 PM MDT | Mesoscale Discussion | SPC | 97 min |
| Jul 21, 6:46 PM MDT | Mesoscale Discussion | SPC | 89 min |
| Jul 29, 5:34 PM MDT | Severe Thunderstorm Warning | ABR | 41 min |
| Aug 1, 9:07 AM MDT | Severe Thunderstorm Warning | ABR | 24 min |
| Aug 2, 4:26 PM MDT | Severe Thunderstorm Warning | ABR | 64 min |
| Aug 5, 10:22 PM MDT | Special Weather Statement | ABR | 53 min |
| Aug 12, 1:36 PM MDT | Mesoscale Discussion | SPC | 114 min |
| Aug 12, 4:46 PM MDT | Mesoscale Discussion | SPC | 89 min |
| Aug 12, 5:12 PM MDT | Special Weather Statement | ABR | 48 min |
| Aug 12, 5:41 PM MDT | Severe Thunderstorm Warning | ABR | 34 min |
| Aug 12, 7:20 PM MDT | Special Weather Statement | ABR | 55 min |
| Aug 12, 7:32 PM MDT | Severe Thunderstorm Warning | ABR | 43 min |
| Aug 12, 8:12 PM MDT | Severe Thunderstorm Warning | ABR | 63 min |
| Aug 17, 3:52 PM MDT | Special Weather Statement | ABR | 83 min |
| Aug 21, 4:41 AM MDT | Severe Thunderstorm Warning | ABR | 64 min |
| Aug 21, 5:36 AM MDT | Severe Thunderstorm Warning | ABR | 34 min |
| Aug 21, 5:56 AM MDT | Special Weather Statement | ABR | 49 min |
| Aug 25, 9:42 AM MDT | Special Weather Statement | ABR | 48 min |
| Aug 26, 4:03 AM MDT | Dense Fog Advisory | ABR | 6 hr |
| Aug 26, 1:13 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 26, 2:04 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 26, 3:24 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 8, 11:49 PM MDT | Special Weather Statement | ABR | 86 min |
| Sep 16, 1:55 PM MDT | Frost Advisory | ABR | 18 hr |
| Sep 19, 12:51 PM MDT | Mesoscale Discussion | SPC | 54 min |
| Oct 3, 1:46 AM MDT | Frost Advisory | ABR | 31 hr |
| Oct 7, 2:29 AM MDT | Wind Advisory | ABR | 12 hr |
| Oct 8, 2:28 AM MDT | Freeze Watch | ABR | 23 hr |
| Oct 9, 1:46 AM MDT | Freeze Warning | ABR | 30 hr |
| Oct 22, 2:03 PM MDT | Wind Advisory | ABR | 28 hr |
| Oct 25, 1:55 PM MDT | Wind Advisory | ABR | 45 hr |
| Oct 29, 2:31 AM MDT | Wind Advisory | ABR | 15 hr |
| Oct 30, 2:39 AM MDT | Wind Advisory | ABR | 13 hr |
| Nov 23, 1:07 PM MST | Wind Advisory | ABR | 24 hr |
| Nov 29, 1:55 AM MST | Wind Advisory | ABR | 21 hr |
| Dec 3, 4:07 AM MST | Winter Weather Advisory | ABR | 37 hr |
| Dec 5, 3:36 AM MST | Wind Advisory | ABR | 14 hr |
| Dec 11, 1:47 AM MST | Wind Advisory | ABR | 12 hr |
| Dec 12, 2:07 PM MST | Wind Advisory | ABR | 23 hr |
| Dec 25, 3:09 AM MST | Wind Chill Advisory | ABR | 32 hr |
| Dec 25, 12:26 PM MST | Wind Chill Warning | ABR | 23 hr |
| Dec 26, 12:37 PM MST | Wind Chill Advisory | ABR | 21 hr |
| Dec 29, 1:18 AM MST | Wind Chill Warning | ABR | 34 hr |
| Dec 29, 1:18 AM MST | Wind Chill Advisory | ABR | 46 hr |
| Dec 30, 1:54 AM MST | Wind Chill Warning | ABR | 57 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 | 18 |
| Severe Thunderstorm Watch | 4 |
| Mesoscale Discussion | 18 |
| Special Weather Statement | 10 |
| Winter | |
| Winter Weather Advisory | 10 |
| Cold | |
| Freeze Warning | 1 |
| Wind Chill Warning | 4 |
| Freeze Watch | 1 |
| Frost Advisory | 4 |
| Wind Chill Advisory | 7 |
| Wind and dust | |
| High Wind Warning | 2 |
| High Wind Watch | 2 |
| Wind Advisory | 11 |
| Fog and smoke | |
| Dense Fog Advisory | 2 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20162018
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.