Alert archive / South Dakota / Tornado Warnings
Tornado Warnings in South Dakota, 2013
25 tornado warnings in 2013. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of tornado warnings reaches back to 1986.
Tornado Warnings by county
Each county as a circle sized by its count in 2013. Tap one for its archive.
- Tornado Warnings
- 25
- Busiest month
- June15 tornado warnings
- Busiest day
- June 21, 201313 tornado warnings
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
8 of 25 tornado warnings covering South Dakota in 2013 had a tornado report inside them; 15 of 21 tornado reports fell inside a warning, on average 17 minutes after it went out.
South Dakota, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 25 | 8 | 68% | 21 | 71% | 17 min |
Each office's whole area, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Rapid City, SD: tornado warnings | 10 | 1 | 90% | 3 | 33% | 4 min |
| NWS Aberdeen, SD: tornado warnings | 15 | 5 | 67% | 9 | 56% | 14 min |
| NWS Sioux Falls, SD: tornado warnings | 20 | 12 | 40% | 38 | 84% | 21 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 | Counties | Lasted |
|---|---|---|---|---|
| May 18, 6:38 PM CDT | Tornado Warning | UNR | Jackson | 52 min |
| Jun 21, 1:25 PM CDT | Tornado Warning | ABR | Spink | 35 min |
| Jun 21, 1:52 PM CDT | Tornado Warning | ABR | Hand, Spink | 23 min |
| Jun 21, 2:03 PM CDT | Tornado Warning | ABR | Spink | 27 min |
| Jun 21, 2:07 PM CDT | Tornado Warning | FSD | Beadle | 38 min |
| Jun 21, 2:11 PM CDT | Tornado Warning | ABR | Hand, Spink | 19 min |
| Jun 21, 2:12 PM CDT | Tornado Warning | ABR | Spink | 33 min |
| Jun 21, 2:38 PM CDT | Tornado Warning | ABR | Clark, Spink | 37 min |
| Jun 21, 2:53 PM CDT | Tornado Warning | FSD | Beadle, Kingsbury | 37 min |
| Jun 21, 2:58 PM CDT | Tornado Warning | ABR | Clark, Spink | 32 min |
| Jun 21, 3:21 PM CDT | Tornado Warning | ABR | Clark, Hamlin | 24 min |
| Jun 21, 3:26 PM CDT | Tornado Warning | ABR | Clark | 34 min |
| Jun 21, 3:41 PM CDT | Tornado Warning | ABR | Codington, Deuel, Hamlin | 34 min |
| Jun 21, 3:43 PM CDT | Tornado Warning | ABR | Clark, Codington, Deuel, Hamlin | 32 min |
| Jun 22, 11:50 PM CDT | Tornado Warning | FSD | Aurora, Jerauld, Sanborn | 25 min |
| Jun 25, 8:04 PM CDT | Tornado Warning | ABR | Campbell, Walworth | 26 min |
| Jul 30, 3:45 PM CDT | Tornado Warning | UNR | Meade, Pennington | 30 min |
| Aug 11, 3:32 PM CDT | Tornado Warning | UNR | Custer, Pennington | 43 min |
| Aug 11, 4:11 PM CDT | Tornado Warning | UNR | Custer | 49 min |
| Aug 13, 7:49 PM CDT | Tornado Warning | UNR | Custer | 26 min |
| Aug 30, 4:46 PM CDT | Tornado Warning | UNR | Custer | 29 min |
| Sep 7, 7:06 PM CDT | Tornado Warning | UNR | Harding | 24 min |
| Oct 4, 6:11 PM CDT | Tornado Warning | FSD | Union | 49 min |
| Oct 4, 6:57 PM CDT | Tornado Warning | FSD | Union | 18 min |
| Oct 11, 11:09 AM CDT | Tornado Warning | ABR | Faulk, Potter | 36 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Spink County7
- Clark County5
- Custer County4
- Hamlin County3
- Hand County2
- Beadle County2
- Codington County2
- Deuel County2
- Pennington County2
- Union County2
- Jackson County1
- Kingsbury County1
- Aurora County1
- Jerauld County1
- Sanborn County1
- Campbell County1
- Walworth County1
- Meade County1
- Harding County1
- Faulk County1
- Potter County1
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20122014
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.