Weather alerts in South Dakota, 2022
2,072 weather alerts in 2022, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered any part of the state, so the counties below add up to more than the state.
Weather alerts by county
Each county as a circle sized by its count in 2022. Tap one for its archive.
- Alerts
- 2,072
- Warnings
- 1,012
- Watches
- 141
- Advisories
- 313
- Busiest month
- June455 alerts
- Busiest day
- May 12, 202296 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
19 of 58 tornado warnings covering South Dakota in 2022 had a tornado report inside them; 21 of 37 tornado reports fell inside a warning, on average 10 minutes after it went out.
South Dakota, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 58 | 19 | 67% | 37 | 57% | 10 min |
| Severe thunderstorm warnings | 704 | 470 | 33% | 1,140 | 84% | 24 min |
| Flash flood warnings | 19 | 9 | 53% | 13 | 69% | 109 min |
Each office's whole area, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Aberdeen, SD: tornado warnings | 33 | 14 | 58% | 28 | 68% | 11 min |
| NWS Aberdeen, SD: severe thunderstorm warnings | 260 | 172 | 34% | 409 | 81% | 23 min |
| NWS Aberdeen, SD: flash flood warnings | 9 | 2 | 78% | 4 | 50% | 18 min |
| NWS Rapid City, SD: tornado warnings | 7 | 0 | 100% | 1 | 0% | |
| NWS Rapid City, SD: severe thunderstorm warnings | 267 | 178 | 33% | 439 | 80% | 26 min |
| NWS Rapid City, SD: flash flood warnings | 6 | 3 | 50% | 5 | 60% | 89 min |
| NWS Sioux Falls, SD: tornado warnings | 34 | 8 | 76% | 24 | 50% | 8 min |
| NWS Sioux Falls, SD: severe thunderstorm warnings | 306 | 208 | 32% | 564 | 90% | 20 min |
| NWS Sioux Falls, SD: flash flood warnings | 6 | 5 | 17% | 9 | 89% | 112 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
2,072 alerts are too many to list on one page. Narrow it to a product above, to a month in the chart, or to a county.
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Pennington County320
- Meade County308
- Custer County229
- Jackson County215
- Lawrence County210
- Todd County206
- Butte County204
- Mellette County203
- Lyman County201
- Jones County191
- Bennett County190
- Dewey County187
- Roberts County187
- Haakon County187
- Stanley County186
- Brown County185
- Oglala Lakota County184
- Edmunds County174
- Spink County174
- Perkins County173
- Harding County171
- Tripp County171
- Faulk County169
- Hand County169
- Hughes County169
- Day County166
- Marshall County166
- Codington County161
- Charles Mix County161
- Hutchinson County161
- Minnehaha County161
- Ziebach County160
- Gregory County159
- Brule County159
- Aurora County158
- Hyde County157
- Fall River County157
- Corson County156
- Grant County156
- Sully County156
26 more counties
- Beadle County155
- Potter County152
- Douglas County152
- Davison County152
- McPherson County151
- Turner County151
- Lake County150
- Jerauld County149
- Sanborn County148
- Walworth County147
- Buffalo County147
- Yankton County147
- McCook County147
- Clark County146
- Hanson County146
- Miner County146
- Campbell County145
- Hamlin County144
- Lincoln County144
- Moody County142
- Brookings County139
- Kingsbury County139
- Deuel County136
- Bon Homme County135
- Clay County131
- Union County125
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20212023
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.