Alert archive / North Dakota / Sioux County

Weather alerts in Sioux County, North Dakota, 2008

116 weather alerts in 2008, 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 2008. Tap one for its archive.

Alerts
116
Warnings
57
Watches
29
Advisories
1
Busiest month
July37 alerts
Busiest day
July 10, 20089 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 3 tornado warnings covering Sioux County in 2008 had a tornado report inside them.

Sioux County, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings3167%0
Severe thunderstorm warnings321069%6100%35 min
Flash flood warnings00

Each office's whole area, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Bismarck, ND: tornado warnings601575%2479%14 min
NWS Bismarck, ND: severe thunderstorm warnings43213469%21690%27 min
NWS Bismarck, ND: flash flood warnings10370%475%10 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 10, 3:28 PM CDTRed Flag WarningBIS4 hr
Mar 24, 5:03 AM CDTRed Flag WarningBIS17 hr
Mar 29, 5:22 AM CDTRed Flag WarningBIS13 hr
Apr 4, 4:55 AM CDTRed Flag WarningBIS16 hr
Apr 13, 4:05 AM CDTFire Weather WatchBIS25 hr
Apr 14, 4:58 AM CDTRed Flag WarningBIS17 hr
Apr 14, 4:08 PM CDTFire Weather WatchBIS12 hr
Apr 15, 4:24 AM CDTRed Flag WarningBIS18 hr
Apr 16, 2:21 PM CDTRed Flag WarningBIS7 hr
Apr 17, 4:03 PM CDTFire Weather WatchBIS13 hr
Apr 18, 4:38 AM CDTRed Flag WarningBIS16 hr
Apr 18, 3:43 PM CDTFire Weather WatchBIS13 hr
Apr 19, 4:37 AM CDTRed Flag WarningBIS20 hr
Apr 20, 5:25 AM CDTRed Flag WarningBIS17 hr
Apr 20, 7:05 PM CDTMesoscale DiscussionSPC55 min
Apr 21, 4:19 PM CDTFire Weather WatchBIS12 hr
Apr 22, 4:45 AM CDTRed Flag WarningBIS17 hr
Apr 27, 4:57 AM CDTRed Flag WarningBIS16 hr
Apr 28, 4:07 AM CDTRed Flag WarningBIS17 hr
May 4, 4:25 AM CDTRed Flag WarningBIS17 hr
May 15, 1:00 PM CDTFire Weather WatchBIS16 hr
May 16, 4:37 AM CDTRed Flag WarningBIS16 hr
May 16, 1:45 PM CDTFire Weather WatchBIS15 hr
May 17, 4:21 AM CDTRed Flag WarningBIS17 hr
May 18, 3:45 PM CDTFire Weather WatchBIS13 hr
May 19, 4:29 AM CDTRed Flag WarningBIS17 hr
May 21, 12:56 PM CDTRed Flag WarningBIS8 hr
May 24, 5:55 PM CDTSevere Thunderstorm WarningBIS50 min
May 24, 6:07 PM CDTMesoscale DiscussionSPC113 min
May 24, 6:24 PM CDTTornado WatchSPC5 hr
May 24, 6:43 PM CDTSevere Thunderstorm WarningBIS62 min
May 24, 9:26 PM CDTMesoscale DiscussionSPC2 hr
May 30, 7:39 PM CDTSevere Thunderstorm WarningBIS66 min
Jun 8, 2:53 PM CDTMesoscale DiscussionSPC2 hr
Jun 11, 1:53 AM CDTAreal Flood AdvisoryBIS9 hr
Jun 11, 2:19 AM CDTSevere Thunderstorm WarningBIS26 min
Jun 11, 2:45 AM CDTSevere Thunderstorm WarningBIS60 min
Jun 13, 5:33 PM CDTMesoscale DiscussionSPC87 min
Jun 14, 1:43 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 18, 4:59 PM CDTSevere Thunderstorm WatchSPC5 hr
Jun 18, 5:33 PM CDTSevere Thunderstorm WarningBIS57 min
Jun 18, 8:32 PM CDTSevere Thunderstorm WarningBIS58 min
Jun 18, 8:46 PM CDTMesoscale DiscussionSPC89 min
Jun 18, 8:56 PM CDTTornado WarningBIS49 min
Jun 18, 9:27 PM CDTSevere Thunderstorm WarningBIS63 min
Jun 24, 12:51 AM CDTSevere Thunderstorm WarningBIS54 min
Jun 24, 2:19 PM CDTMesoscale DiscussionSPC86 min
Jun 24, 2:51 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 24, 6:39 PM CDTSevere Thunderstorm WarningBIS66 min
Jun 24, 7:00 PM CDTMesoscale DiscussionSPC60 min
Jun 24, 7:46 PM CDTSevere Thunderstorm WarningBIS59 min
Jun 24, 7:52 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 26, 1:59 PM CDTSevere Thunderstorm WatchSPC5 hr
Jun 26, 5:43 PM CDTSevere Thunderstorm WarningBIS47 min
Jun 26, 6:28 PM CDTMesoscale DiscussionSPC62 min
Jun 26, 6:46 PM CDTSevere Thunderstorm WatchSPC5 hr
Jun 26, 7:15 PM CDTSevere Thunderstorm WarningBIS60 min
Jun 26, 7:50 PM CDTSevere Thunderstorm WarningBIS25 min
Jun 26, 8:15 PM CDTSevere Thunderstorm WarningBIS60 min
Jul 7, 3:26 PM CDTSevere Thunderstorm WatchSPC5 hr
Jul 9, 7:34 PM CDTSevere Thunderstorm WarningBIS56 min
Jul 10, 3:46 PM CDTMesoscale DiscussionSPC59 min
Jul 10, 4:11 PM CDTTornado WatchSPC7 hr
Jul 10, 4:29 PM CDTFire Weather WatchBIS13 hr
Jul 10, 4:41 PM CDTSevere Thunderstorm WarningBIS64 min
Jul 10, 5:44 PM CDTSevere Thunderstorm WarningBIS61 min
Jul 10, 5:50 PM CDTTornado WarningBIS40 min
Jul 10, 6:03 PM CDTMesoscale DiscussionSPC57 min
Jul 10, 6:45 PM CDTSevere Thunderstorm WarningBIS60 min
Jul 11, 5:18 AM CDTRed Flag WarningBIS16 hr
Jul 15, 5:39 PM CDTSevere Thunderstorm WarningBIS51 min
Jul 15, 8:07 PM CDTSevere Thunderstorm WarningBIS53 min
Jul 19, 2:53 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 19, 7:38 PM CDTSevere Thunderstorm WarningBIS67 min
Jul 23, 5:23 PM CDTSevere Thunderstorm WarningBIS67 min
Jul 23, 6:24 PM CDTTornado WarningBIS36 min
Jul 23, 6:24 PM CDTMesoscale DiscussionSPC2 hr
Jul 23, 6:51 PM CDTSevere Thunderstorm WatchSPC4 hr
Jul 23, 6:57 PM CDTSevere Thunderstorm WarningBIS29 min
Jul 26, 9:57 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 27, 2:25 AM CDTMesoscale DiscussionSPC95 min
Jul 27, 2:40 AM CDTSevere Thunderstorm WarningBIS65 min
Jul 27, 3:14 AM CDTSevere Thunderstorm WatchSPC5 hr
Jul 27, 3:39 AM CDTSevere Thunderstorm WarningBIS66 min
Jul 27, 3:44 AM CDTSevere Thunderstorm WarningBIS61 min
Jul 28, 3:38 PM CDTMesoscale DiscussionSPC67 min
Jul 28, 7:34 PM CDTTornado WatchSPC4 hr
Jul 30, 3:39 PM CDTMesoscale DiscussionSPC66 min
Jul 30, 4:07 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 30, 7:04 PM CDTMesoscale DiscussionSPC56 min
Jul 30, 7:19 PM CDTSevere Thunderstorm WarningBIS33 min
Jul 30, 10:04 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 31, 12:46 AM CDTSevere Thunderstorm WarningBIS59 min
Jul 31, 12:50 AM CDTMesoscale DiscussionSPC85 min
Jul 31, 1:48 AM CDTSevere Thunderstorm WarningBIS57 min
Jul 31, 3:30 AM CDTMesoscale DiscussionSPC90 min
Aug 3, 12:05 AM CDTSevere Thunderstorm WatchSPC8 hr
Aug 3, 4:10 AM CDTMesoscale DiscussionSPC95 min
Aug 11, 2:34 PM CDTSevere Thunderstorm WarningBIS41 min
Aug 26, 2:33 PM CDTMesoscale DiscussionSPC2 hr
Aug 26, 8:21 PM CDTSevere Thunderstorm WarningBIS54 min
Aug 29, 3:54 AM CDTFire Weather WatchBIS24 hr
Aug 30, 4:11 AM CDTRed Flag WarningBIS18 hr
Aug 30, 4:11 PM CDTFire Weather WatchBIS11 hr
Aug 31, 3:37 AM CDTRed Flag WarningBIS18 hr
Sep 22, 5:10 PM CDTMesoscale DiscussionSPC65 min
Sep 22, 7:35 PM CDTSevere Thunderstorm WatchSPC8 hr
Sep 22, 10:21 PM CDTMesoscale DiscussionSPC54 min
Sep 23, 1:13 PM CDTMesoscale DiscussionSPC2 hr
Oct 7, 3:56 PM CDTRed Flag WarningBIS29 hr
Nov 6, 12:38 PM CSTMesoscale DiscussionSPC4 hr
Nov 6, 6:32 PM CSTMesoscale DiscussionSPC4 hr
Nov 14, 2:17 PM CSTMesoscale DiscussionSPC58 min
Dec 2, 12:29 PM CSTMesoscale DiscussionSPC4 hr
Dec 13, 6:29 PM CSTMesoscale DiscussionSPC4 hr
Dec 26, 11:56 AM CSTMesoscale DiscussionSPC4 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 archive20072009

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.