Alert archive / South Dakota / Sully County

Weather alerts in Sully County, South Dakota, 2020

135 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Sully County and its neighbors

Each county as a circle sized by its count in 2020. Tap one for its archive.

Alerts
135
Warnings
41
Watches
16
Advisories
38
Busiest month
July37 alerts
Busiest day
June 7, 202010 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

Sully County, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings321941%3100%25 min
Flash flood warnings10100%0

Each office's whole area, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Aberdeen, SD: tornado warnings11373%1619%6 min
NWS Aberdeen, SD: severe thunderstorm warnings26216039%35678%19 min
NWS Aberdeen, SD: flash flood warnings4175%1100%205 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.

IssuedProductOfficeLasted
Jan 4, 1:29 PM CSTWind AdvisoryABR23 hr
Jan 10, 2:25 PM CSTWind Chill AdvisoryABR22 hr
Jan 15, 3:54 AM CSTWind Chill AdvisoryABR32 hr
Jan 16, 1:35 PM CSTWinter Weather AdvisoryABR31 hr
Jan 17, 3:31 AM CSTHigh Wind WarningABR26 hr
Jan 18, 3:38 AM CSTWind Chill AdvisoryABR32 hr
Jan 24, 3:55 AM CSTDense Fog AdvisoryABR31 hr
Jan 28, 8:10 PM CSTDense Fog AdvisoryABR16 hr
Jan 29, 12:02 PM CSTDense Fog AdvisoryABR3 hr
Jan 29, 3:02 PM CSTDense Fog AdvisoryABR21 hr
Feb 7, 10:45 AM CSTWinter Storm WatchABR24 hr
Feb 8, 10:28 AM CSTWinter Storm WarningABR21 hr
Feb 8, 7:46 PM CSTMesoscale DiscussionSPC4 hr
Feb 11, 2:38 PM CSTBlizzard WarningABR21 hr
Feb 11, 2:38 PM CSTWind Chill WarningABR43 hr
Feb 11, 2:38 PM CSTWind Chill AdvisoryABR43 hr
Feb 11, 2:38 PM CSTWinter Weather AdvisoryABR27 hr
Feb 17, 1:14 AM CSTDense Fog AdvisoryABR8 hr
Feb 24, 3:05 AM CSTWinter Weather AdvisoryABR28 hr
Mar 4, 2:44 PM CSTWind AdvisoryABR27 hr
Mar 4, 4:51 PM CSTMesoscale DiscussionSPC114 min
Mar 19, 3:22 AM CDTWind AdvisoryABR21 hr
Mar 27, 8:56 AM CDTDense Fog AdvisoryABR3 hr
Apr 1, 4:00 AM CDTWinter Weather AdvisoryABR51 hr
Apr 8, 3:14 AM CDTWind AdvisoryABR17 hr
Apr 16, 4:13 AM CDTDense Fog AdvisoryABR6 hr
Apr 20, 3:34 AM CDTWind AdvisoryABR15 hr
Apr 28, 5:31 PM CDTMesoscale DiscussionSPC119 min
May 8, 9:36 PM CDTWind AdvisoryABR23 hr
May 23, 7:53 PM CDTMesoscale DiscussionSPC97 min
Jun 4, 3:27 PM CDTSevere Thunderstorm WatchSPC8 hr
Jun 6, 5:49 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 6, 8:29 PM CDTMesoscale DiscussionSPC91 min
Jun 6, 9:36 PM CDTSevere Thunderstorm WarningABR39 min
Jun 6, 9:59 PM CDTSevere Thunderstorm WarningABR46 min
Jun 6, 10:52 PM CDTSevere Thunderstorm WarningABR35 min
Jun 7, 2:04 PM CDTMesoscale DiscussionSPC116 min
Jun 7, 3:31 PM CDTSevere Thunderstorm WatchSPC8 hr
Jun 7, 5:07 PM CDTSevere Thunderstorm WarningABR38 min
Jun 7, 5:32 PM CDTSevere Thunderstorm WarningABR43 min
Jun 7, 6:00 PM CDTMesoscale DiscussionSPC90 min
Jun 7, 6:14 PM CDTSevere Thunderstorm WarningABR29 min
Jun 7, 7:15 PM CDTSevere Thunderstorm WarningABR45 min
Jun 7, 7:24 PM CDTSevere Thunderstorm WarningABR22 min
Jun 7, 8:15 PM CDTSevere Thunderstorm WarningABR34 min
Jun 7, 8:30 PM CDTSevere Thunderstorm WarningABR30 min
Jun 7, 8:34 PM CDTSevere Thunderstorm WarningABR26 min
Jun 7, 8:59 PM CDTSevere Thunderstorm WarningABR31 min
Jun 7, 9:18 PM CDTMesoscale DiscussionSPC57 min
Jun 7, 10:50 PM CDTSevere Thunderstorm WarningABR25 min
Jun 16, 3:16 AM CDTWind AdvisoryABR18 hr
Jun 17, 5:26 PM CDTMesoscale DiscussionSPC2 hr
Jun 17, 6:29 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 17, 9:23 PM CDTMesoscale DiscussionSPC2 hr
Jun 17, 11:16 PM CDTMesoscale DiscussionSPC89 min
Jun 20, 3:03 PM CDTSevere Thunderstorm WarningABR16 min
Jun 20, 3:20 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 25, 1:16 PM CDTMesoscale DiscussionSPC119 min
Jun 28, 3:41 PM CDTHeat AdvisoryABR28 hr
Jun 28, 8:55 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 28, 11:16 PM CDTMesoscale DiscussionSPC119 min
Jul 2, 2:15 PM CDTSevere Thunderstorm WatchSPC9 hr
Jul 2, 8:07 PM CDTSevere Thunderstorm WarningABR38 min
Jul 2, 8:33 PM CDTSevere Thunderstorm WarningABR42 min
Jul 2, 8:46 PM CDTMesoscale DiscussionSPC59 min
Jul 2, 9:03 PM CDTSpecial Weather StatementABR42 min
Jul 5, 3:32 PM CDTMesoscale DiscussionSPC118 min
Jul 5, 4:41 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 5, 6:29 PM CDTMesoscale DiscussionSPC2 hr
Jul 5, 8:33 PM CDTMesoscale DiscussionSPC117 min
Jul 6, 9:07 PM CDTMesoscale DiscussionSPC83 min
Jul 6, 11:13 PM CDTSevere Thunderstorm WarningABR47 min
Jul 7, 8:02 PM CDTMesoscale DiscussionSPC118 min
Jul 7, 8:17 PM CDTSevere Thunderstorm WatchSPC5 hr
Jul 7, 10:48 PM CDTSevere Thunderstorm WarningABR42 min
Jul 10, 9:13 AM CDTMesoscale DiscussionSPC62 min
Jul 10, 1:26 PM CDTMesoscale DiscussionSPC2 hr
Jul 10, 2:08 PM CDTSevere Thunderstorm WatchSPC8 hr
Jul 10, 3:43 PM CDTMesoscale DiscussionSPC2 hr
Jul 16, 2:23 PM CDTHeat AdvisoryABR30 hr
Jul 20, 12:16 PM CDTMesoscale DiscussionSPC119 min
Jul 20, 1:13 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 20, 1:28 PM CDTSevere Thunderstorm WarningABR62 min
Jul 20, 2:21 PM CDTSevere Thunderstorm WarningABR54 min
Jul 20, 3:19 PM CDTMesoscale DiscussionSPC116 min
Jul 22, 8:08 AM CDTSevere Thunderstorm WarningABR52 min
Jul 22, 8:47 AM CDTSevere Thunderstorm WarningABR43 min
Jul 22, 8:49 AM CDTMesoscale DiscussionSPC86 min
Jul 22, 9:38 AM CDTSevere Thunderstorm WarningABR15 min
Jul 22, 9:46 AM CDTSevere Thunderstorm WarningABR44 min
Jul 22, 10:12 AM CDTFlash Flood WarningABR3 hr
Jul 23, 3:03 AM CDTHeat AdvisoryABR65 hr
Jul 24, 2:50 PM CDTMesoscale DiscussionSPC115 min
Jul 24, 3:21 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 24, 7:28 PM CDTMesoscale DiscussionSPC2 hr
Jul 25, 8:34 PM CDTSevere Thunderstorm WarningABR25 min
Jul 31, 2:54 PM CDTMesoscale DiscussionSPC2 hr
Jul 31, 6:23 PM CDTSevere Thunderstorm WarningABR52 min
Aug 6, 5:01 AM CDTDense Fog AdvisoryABR5 hr
Aug 7, 12:48 AM CDTSpecial Weather StatementABR42 min
Aug 7, 1:10 AM CDTSevere Thunderstorm WarningABR50 min
Aug 8, 10:10 PM CDTSevere Thunderstorm WatchSPC6 hr
Aug 12, 12:36 AM CDTMesoscale DiscussionSPC84 min
Aug 18, 4:15 AM CDTSpecial Weather StatementABR45 min
Aug 18, 4:33 AM CDTSevere Thunderstorm WarningABR57 min
Aug 18, 5:09 AM CDTSpecial Weather StatementABR36 min
Aug 23, 5:10 PM CDTMesoscale DiscussionSPC95 min
Aug 23, 7:23 PM CDTSpecial Weather StatementABR52 min
Aug 23, 7:34 PM CDTSpecial Weather StatementABR41 min
Aug 25, 3:23 AM CDTHeat AdvisoryABR17 hr
Aug 26, 3:59 PM CDTMesoscale DiscussionSPC2 hr
Aug 26, 4:45 PM CDTSevere Thunderstorm WarningABR45 min
Aug 27, 9:20 PM CDTMesoscale DiscussionSPC85 min
Aug 27, 10:20 PM CDTSevere Thunderstorm WatchSPC5 hr
Aug 27, 10:54 PM CDTSevere Thunderstorm WarningABR36 min
Aug 27, 11:12 PM CDTSevere Thunderstorm WarningABR48 min
Aug 27, 11:30 PM CDTMesoscale DiscussionSPC2 hr
Aug 27, 11:42 PM CDTSevere Thunderstorm WarningABR78 min
Aug 30, 3:22 PM CDTMesoscale DiscussionSPC113 min
Sep 2, 3:24 AM CDTWind AdvisoryABR24 hr
Sep 8, 3:29 PM CDTFrost AdvisoryABR18 hr
Sep 29, 2:30 PM CDTWind AdvisoryABR30 hr
Oct 1, 3:10 AM CDTFrost AdvisoryABR29 hr
Oct 3, 2:21 PM CDTFrost AdvisoryABR19 hr
Oct 13, 3:52 PM CDTHigh Wind WarningABR27 hr
Oct 21, 3:08 PM CDTWinter Weather AdvisoryABR30 hr
Oct 23, 2:35 PM CDTWinter Storm WarningABR43 hr
Oct 23, 2:35 PM CDTWinter Weather AdvisoryABR48 hr
Oct 30, 1:47 PM CDTWind AdvisoryABR30 hr
Oct 31, 11:47 AM CDTHigh Wind WarningABR8 hr
Nov 7, 1:21 PM CSTWind AdvisoryABR29 hr
Dec 21, 2:01 PM CSTHigh Wind WatchABR25 hr
Dec 22, 2:23 PM CSTWinter Weather AdvisoryABR24 hr
Dec 22, 2:31 PM CSTHigh Wind WarningABR24 hr
Dec 28, 3:56 AM CSTWinter Weather AdvisoryABR44 hr

By product

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

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20192021

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.