Alert archive / South Dakota

Weather alerts in Brookings County, South Dakota

2,817 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Brookings County and its neighbors

Each county as a circle sized by its count since 1986. Tap one for its archive.

Alerts
2,817
Warnings
798
Watches
493
Advisories
904
Busiest year
2010184 alerts
Average year
70over 40 years on file

Over time

By year

Before late 2005 the archive holds only tornado, severe thunderstorm, flash flood and marine warnings, and from 1997 SPC's watches, so the jump that year is the archive widening, not 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, 50% of tornado reports in Brookings County fell inside a tornado warning issued on average 10 minutes before, and 78% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20094175%0
2011110%0
201410100%0
2015220%2100%8 min
201630100%0
201750100%0
201920100%0
202020100%0
202220100%20%
20233233%450%12 min
202420100%0
Share of tornado reports inside a tornado warning, by year.

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20089456%580%3 min
20098625%450%22 min
2010221914%15100%31 min
20117614%4100%24 min
2012171418%8100%26 min
20136517%6100%27 min
20143233%2100%10 min
201512118%1090%23 min
2016191047%956%10 min
2017292610%1292%17 min
201850100%10%
2019770%3100%13 min
20209811%888%25 min
2021550%650%21 min
2022241442%1479%17 min
202310640%580%11 min
20246433%667%18 min
2025271930%1794%17 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2009110%0
2010660%989%53 min
2011110%250%19 min
201310100%0
20145420%2100%97 min
2016220%2100%31 min
20182150%367%136 min
2019220%425%59 min
2024220%667%49 min
202510100%0

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 product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The latest warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Sep 11, 6:54 PM CDTSevere Thunderstorm WarningFSD51 min
Sep 6, 2:07 PM CDTFlash Flood WarningFSD4 hr
Aug 25, 3:23 AM CDTSevere Thunderstorm WarningFSD52 min
Aug 7, 5:43 AM CDTSevere Thunderstorm WarningFSD25 min
Jul 24, 11:24 PM CDTExtreme Heat WarningFSD46 hr
Jul 10, 2:58 AM CDTRiver Flood WarningFSD49 hr
Jul 9, 12:15 AM CDTRiver Flood WarningFSD21 days
Jul 2, 7:13 PM CDTSevere Thunderstorm WarningFSD47 min
Jul 2, 5:41 PM CDTSevere Thunderstorm Warning Considerable damage threatFSD49 min
Jun 10, 12:13 AM CDTSevere Thunderstorm Warning Considerable damage threatFSD36 min
Jun 10, 12:06 AM CDTSevere Thunderstorm WarningFSD39 min
Jun 5, 6:58 AM CDTRiver Flood WarningFSD71 hr

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive

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.