Alert archive / Minnesota / Swift County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Swift County, Minnesota, 2012

17 severe thunderstorm warnings in 2012. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Swift County and its neighbors

Each county as a circle sized by its count in 2012. Tap one for its archive.

Severe Thunderstorm Warnings
17
Busiest month
June9 severe thunderstorm warnings
Busiest day
June 18, 20126 severe thunderstorm warnings

Over time

By month

Warning verification

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

12 of 17 severe thunderstorm warnings covering Swift County in 2012 had a qualifying storm report inside them; 3 of 4 hail, wind and damage reports fell inside a warning, on average 28 minutes after it went out.

Swift County, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings171229%475%28 min

Each office's whole area, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Twin Cities, MN: severe thunderstorm warnings28214549%47070%22 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
May 2, 9:25 PM CDTSevere Thunderstorm WarningMPX50 min
May 2, 10:12 PM CDTSevere Thunderstorm WarningMPX48 min
May 2, 10:55 PM CDTSevere Thunderstorm WarningMPX50 min
Jun 10, 4:01 PM CDTSevere Thunderstorm WarningMPX29 min
Jun 17, 6:08 PM CDTSevere Thunderstorm WarningMPX67 min
Jun 17, 7:06 PM CDTSevere Thunderstorm WarningMPX39 min
Jun 17, 7:21 PM CDTSevere Thunderstorm WarningMPX39 min
Jun 17, 7:53 PM CDTSevere Thunderstorm WarningMPX67 min
Jun 17, 7:58 PM CDTSevere Thunderstorm WarningMPX47 min
Jun 17, 8:33 PM CDTSevere Thunderstorm WarningMPX42 min
Jun 17, 8:45 PM CDTSevere Thunderstorm WarningMPX45 min
Jun 19, 8:19 PM CDTSevere Thunderstorm WarningMPX40 min
Jul 12, 10:25 PM CDTSevere Thunderstorm WarningMPX35 min
Aug 3, 8:20 PM CDTSevere Thunderstorm WarningMPX55 min
Aug 3, 9:07 PM CDTSevere Thunderstorm WarningMPX53 min
Aug 15, 6:01 PM CDTSevere Thunderstorm WarningMPX59 min
Aug 15, 6:36 PM CDTSevere Thunderstorm WarningMPX54 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20112013

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.