Alert archive / Minnesota / Grant County

Severe Thunderstorm Warnings in Grant County, Minnesota

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

Grant County and its neighbors

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

Severe Thunderstorm Warnings
237
Busiest year
201119 severe thunderstorm warnings
Average year
6over 39 years on file

Over time

By year

Before October 2007 these were issued for whole counties, and a storm crossing three counties was often three warnings; since then one polygon follows the storm. The count changed with the practice, not only with the weather.

Warning verification

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

From 2008 to 2025, 77% of hail, wind and damage reports in Grant County fell inside a severe thunderstorm warning issued on average 21 minutes before, and 25% of the severe thunderstorm warnings had no report inside them.

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200813469%450%18 min
2009220%2100%25 min
20108450%520%23 min
2011201145%9100%30 min
20124325%3100%20 min
2013660%4100%21 min
2014110%250%18 min
201510100%10%
2016141214%6100%32 min
201712118%989%19 min
20186517%0
20196517%4100%14 min
202014137%1471%22 min
2021990%1070%11 min
202210910%2070%22 min
20232150%250%31 min
202412925%367%11 min
20258625%6100%6 min

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.

The latest severe thunderstorm warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Sep 11, 6:28 PM CDTSevere Thunderstorm WarningFGF62 min
Jul 6, 9:54 PM CDTSevere Thunderstorm WarningFGF36 min
Jul 6, 9:08 PM CDTSevere Thunderstorm WarningFGF52 min
Jul 6, 8:39 PM CDTSevere Thunderstorm WarningFGF81 min
Jun 29, 10:06 AM CDTSevere Thunderstorm WarningFGF54 min
Jun 29, 9:28 AM CDTSevere Thunderstorm Warning Considerable damage threatFGF62 min
Jun 23, 2:59 PM CDTSevere Thunderstorm WarningFGF38 min
Jun 10, 2:17 AM CDTSevere Thunderstorm Warning Destructive damage threatFGF58 min
Jun 10, 1:26 AM CDTSevere Thunderstorm WarningFGF64 min

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.