Alert archive / North Dakota / Sioux County

Weather alerts in Sioux County, North Dakota, 2024

72 weather alerts in 2024, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Sioux County and its neighbors

Each county as a circle sized by its count in 2024. Tap one for its archive.

Alerts
72
Warnings
29
Watches
19
Advisories
1
Busiest month
June19 alerts
Busiest day
August 28, 20248 alerts

Over time

By month

Warning verification

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

1 of 2 tornado warnings covering Sioux County in 2024 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 6 minutes after it went out.

Sioux County, 2024

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings2150%1100%6 min
Severe thunderstorm warnings191237%1182%24 min
Flash flood warnings00

Each office's whole area, 2024

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Bismarck, ND: tornado warnings17476%1040%11 min
NWS Bismarck, ND: severe thunderstorm warnings21214930%31686%24 min
NWS Bismarck, ND: flash flood warnings6267%2100%39 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
Mar 15, 3:36 AM CDTRed Flag WarningBIS16 hr
Apr 5, 3:14 AM CDTRed Flag WarningBIS16 hr
Apr 21, 2:48 AM CDTFire Weather WatchBIS24 hr
Apr 22, 2:52 AM CDTRed Flag WarningBIS17 hr
Apr 28, 2:50 PM CDTFire Weather WatchBIS36 hr
May 6, 12:18 PM CDTSevere Thunderstorm WatchSPC8 hr
May 17, 2:30 PM CDTSevere Thunderstorm WatchSPC7 hr
May 17, 5:04 PM CDTMesoscale DiscussionSPC116 min
May 17, 6:26 PM CDTSevere Thunderstorm WarningBIS64 min
May 19, 1:09 PM CDTMesoscale DiscussionSPC2 hr
May 19, 6:50 PM CDTSevere Thunderstorm WarningBIS38 min
May 19, 7:12 PM CDTSevere Thunderstorm WatchSPC4 hr
May 19, 7:15 PM CDTSevere Thunderstorm WarningBIS45 min
May 19, 7:28 PM CDTSevere Thunderstorm WarningBIS47 min
May 19, 7:58 PM CDTSevere Thunderstorm Warning Considerable damage threatBIS47 min
May 23, 3:25 PM CDTSevere Thunderstorm WatchSPC8 hr
May 23, 7:15 PM CDTSevere Thunderstorm WarningBIS60 min
May 29, 10:48 PM CDTSpecial Weather StatementBIS42 min
Jun 2, 2:01 PM CDTMesoscale DiscussionSPC2 hr
Jun 2, 3:51 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 2, 5:00 PM CDTSevere Thunderstorm WarningBIS45 min
Jun 2, 6:18 PM CDTMesoscale DiscussionSPC72 min
Jun 2, 6:38 PM CDTSevere Thunderstorm WarningBIS33 min
Jun 3, 7:56 PM CDTSevere Thunderstorm WarningBIS29 min
Jun 7, 6:16 PM CDTMesoscale DiscussionSPC89 min
Jun 15, 5:11 PM CDTMesoscale DiscussionSPC94 min
Jun 15, 7:55 PM CDTMesoscale DiscussionSPC65 min
Jun 15, 10:08 PM CDTMesoscale DiscussionSPC67 min
Jun 17, 9:19 PM CDTMesoscale DiscussionSPC116 min
Jun 17, 10:42 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 17, 10:53 PM CDTSpecial Weather StatementBIS37 min
Jun 27, 6:21 PM CDTMesoscale DiscussionSPC84 min
Jun 27, 7:01 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 27, 8:04 PM CDTSevere Thunderstorm Warning Destructive damage threatBIS56 min
Jun 27, 8:11 PM CDTMesoscale DiscussionSPC94 min
Jun 27, 8:52 PM CDTSevere Thunderstorm Warning Considerable damage threatBIS53 min
Jun 27, 9:50 PM CDTMesoscale DiscussionSPC115 min
Jul 1, 2:16 PM CDTMesoscale DiscussionSPC119 min
Jul 1, 3:44 PM CDTSevere Thunderstorm WatchSPC4 hr
Jul 12, 4:05 PM CDTMesoscale DiscussionSPC115 min
Jul 12, 7:28 PM CDTSevere Thunderstorm WatchSPC5 hr
Jul 12, 9:56 PM CDTSevere Thunderstorm WarningBIS43 min
Jul 12, 10:06 PM CDTMesoscale DiscussionSPC84 min
Jul 29, 3:52 AM CDTSevere Thunderstorm WarningBIS53 min
Jul 29, 4:48 AM CDTSpecial Weather StatementBIS42 min
Jul 29, 3:38 PM CDTMesoscale DiscussionSPC67 min
Jul 29, 4:26 PM CDTSevere Thunderstorm WatchSPC8 hr
Jul 29, 6:49 PM CDTMesoscale DiscussionSPC86 min
Jul 29, 7:13 PM CDTSevere Thunderstorm WarningBIS47 min
Jul 29, 8:02 PM CDTSevere Thunderstorm WarningBIS58 min
Jul 30, 3:03 PM CDTMesoscale DiscussionSPC117 min
Jul 30, 4:37 PM CDTSevere Thunderstorm WatchSPC5 hr
Aug 28, 3:51 PM CDTMesoscale DiscussionSPC2 hr
Aug 28, 4:41 PM CDTTornado WatchSPC6 hr
Aug 28, 5:14 PM CDTSevere Thunderstorm Warning Considerable damage threatBIS61 min
Aug 28, 5:17 PM CDTSevere Thunderstorm Warning Considerable damage threatBIS58 min
Aug 28, 5:35 PM CDTTornado WarningBIS25 min
Aug 28, 5:55 PM CDTTornado Warning Tornado observedBIS50 min
Aug 28, 6:09 PM CDTSevere Thunderstorm Warning Considerable damage threatBIS66 min
Aug 28, 6:45 PM CDTAreal Flood AdvisoryBIS6 hr
Aug 28, 7:09 PM CDTSevere Thunderstorm WarningBIS49 min
Sep 11, 1:40 PM CDTFire Weather WatchBIS12 hr
Sep 12, 2:09 AM CDTRed Flag WarningBIS18 hr
Sep 16, 3:00 AM CDTMesoscale DiscussionSPC2 hr
Sep 28, 3:16 AM CDTFire Weather WatchBIS11 hr
Sep 28, 2:29 PM CDTRed Flag WarningBIS53 hr
Sep 29, 2:35 AM CDTFire Weather WatchBIS13 hr
Oct 1, 2:51 AM CDTRed Flag WarningBIS16 hr
Oct 3, 3:20 AM CDTFire Weather WatchBIS34 hr
Oct 4, 1:02 PM CDTRed Flag WarningBIS32 hr
Oct 15, 2:08 AM CDTFire Weather WatchBIS12 hr
Oct 15, 2:03 PM CDTRed Flag WarningBIS29 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 archive20232025

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.