Severe Thunderstorm Warnings in South Dakota
21,462 severe thunderstorm warnings since 1986. 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 severe thunderstorm warnings reaches back to 1986.
Severe Thunderstorm Warnings by county
Each county as a circle sized by its count since 1986. Tap one for its archive.
- Severe Thunderstorm Warnings
- 21,462
- Busiest year
- 2008844 severe thunderstorm warnings
- Average year
- 523over 41 years on file
Over time
By year
Before October 2007 these were issued for whole counties, and a storm crossing three counties was often three warnings; since then one polygon follows the storm. The count changed with the practice, not only with the weather.
By month of the year
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
From 2008 to 2025, 84% of hail, wind and damage reports in South Dakota fell inside a severe thunderstorm warning issued on average 23 minutes before, and 33% of the severe thunderstorm warnings had no report inside them.
Severe thunderstorm warnings by year
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| 2008 | 844 | 424 | 50% | 688 | 85% | 25 min |
| 2009 | 521 | 342 | 34% | 689 | 75% | 22 min |
| 2010 | 688 | 518 | 25% | 990 | 86% | 23 min |
| 2011 | 755 | 541 | 28% | 927 | 87% | 23 min |
| 2012 | 537 | 379 | 29% | 721 | 86% | 23 min |
| 2013 | 627 | 454 | 28% | 854 | 88% | 23 min |
| 2014 | 461 | 303 | 34% | 538 | 82% | 20 min |
| 2015 | 582 | 439 | 25% | 822 | 88% | 24 min |
| 2016 | 724 | 492 | 32% | 935 | 85% | 23 min |
| 2017 | 544 | 396 | 27% | 723 | 87% | 22 min |
| 2018 | 621 | 419 | 33% | 840 | 83% | 22 min |
| 2019 | 635 | 428 | 33% | 806 | 87% | 22 min |
| 2020 | 764 | 562 | 26% | 1,233 | 85% | 24 min |
| 2021 | 475 | 328 | 31% | 688 | 78% | 22 min |
| 2022 | 704 | 470 | 33% | 1,140 | 84% | 24 min |
| 2023 | 541 | 354 | 35% | 736 | 81% | 23 min |
| 2024 | 524 | 341 | 35% | 890 | 79% | 24 min |
| 2025 | 785 | 452 | 42% | 1,090 | 78% | 25 min |
Years from 2008, the first full year of storm-based warnings. The year still running is on its own page.
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.
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Pennington County2,096
- Meade County1,725
- Custer County1,247
- Jackson County907
- Dewey County883
- Butte County835
- Perkins County806
- Corson County784
- Lawrence County783
- Lyman County744
- Fall River County743
- Haakon County729
- Brown County724
- Stanley County708
- Todd County707
- Charles Mix County695
- Edmunds County663
- Harding County662
- Hand County661
- Mellette County653
- Spink County653
- Hughes County618
- Bennett County612
- Ziebach County608
- Minnehaha County602
- Tripp County602
- McPherson County597
- Sully County577
- Faulk County571
- Hutchinson County546
- Hyde County542
- Beadle County540
- Turner County536
- Lincoln County532
- Gregory County518
- Walworth County516
- Potter County513
- McCook County508
- Day County507
- Jones County497
26 more counties
- Union County491
- Roberts County481
- Aurora County476
- Campbell County470
- Brule County458
- Yankton County457
- Miner County456
- Oglala Lakota County441
- Kingsbury County439
- Codington County427
- Sanborn County423
- Davison County417
- Clark County416
- Bon Homme County414
- Lake County411
- Clay County409
- Hanson County404
- Marshall County388
- Douglas County385
- Moody County373
- Brookings County364
- Buffalo County364
- Grant County361
- Jerauld County347
- Hamlin County332
- Deuel County281
The latest severe thunderstorm warnings
The most recent on file, newest first.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 27, 11:45 AM CDT | Severe Thunderstorm Warning | ABR | Stanley | 49 min |
| Sep 27, 9:58 AM CDT | Severe Thunderstorm Warning | ABR | Sully | 41 min |
| Sep 27, 9:13 AM CDT | Severe Thunderstorm Warning | ABR | Dewey, Stanley, Sully | 47 min |
| Sep 23, 7:15 PM CDT | Severe Thunderstorm Warning | UNR | Perkins | 60 min |
| Sep 23, 6:24 PM CDT | Severe Thunderstorm Warning | UNR | Perkins | 51 min |
| Sep 14, 4:09 AM CDT | Severe Thunderstorm Warning | FSD | Aurora, Jerauld | 18 min |
| Sep 11, 9:24 PM CDT | Severe Thunderstorm Warning | FSD | Clay, Union | 51 min |
| Sep 11, 7:48 PM CDT | Severe Thunderstorm Warning | FSD | Lincoln, McCook, Minnehaha, Turner | 22 min |
| Sep 11, 7:19 PM CDT | Severe Thunderstorm Warning | ABR | Grant, Roberts | 27 min |
| Sep 11, 6:54 PM CDT | Severe Thunderstorm Warning | FSD | Brookings, Lake, Moody | 51 min |
| Sep 7, 11:55 PM CDT | Severe Thunderstorm Warning | FSD | Aurora, Charles Mix, Davison, Douglas, Hanson, Hutchinson and 1 more | 50 min |
| Sep 7, 11:42 PM CDT | Severe Thunderstorm Warning | FSD | Lincoln, Minnehaha | 48 min |
Nearby
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.