Alert archive / Minnesota

Weather alerts in Hennepin County, Minnesota

2,882 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Hennepin County and its neighbors

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

Alerts
2,882
Warnings
873
Watches
520
Advisories
614
Busiest year
2012151 alerts
Average year
70over 41 years on file

Over time

By year

Before late 2005 the archive holds only tornado, severe thunderstorm, flash flood and marine warnings, and from 1997 SPC's watches, so the jump that year is the archive widening, not the weather.

By month of the year

Warning verification

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

From 2008 to 2025, 75% of tornado reports in Hennepin County fell inside a tornado warning issued on average 8 minutes before, and 59% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200820100%0
20093167%475%4 min
20103233%1100%10 min
20118538%5100%9 min
201510100%0
20172150%0
201910100%10%
202010100%10%
20222150%0
20254175%0
Share of tornado reports inside a tornado warning, by year.

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008171135%4796%33 min
20096433%1520%9 min
2010171418%2580%23 min
201118176%4448%33 min
2012322134%2374%21 min
201310100%6679%33 min
20145260%425%10 min
201511918%3992%19 min
2016181422%2969%29 min
20176517%2171%26 min
2018191426%2836%21 min
2019171418%2879%25 min
2020211624%4398%22 min
202110640%1850%15 min
2022171512%3379%23 min
202312118%4279%26 min
202413130%4180%18 min
2025211529%2785%20 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008010%
20092150%1100%62 min
2010440%1164%52 min
20113233%367%70 min
201220100%10%
20133233%683%40 min
20144175%4100%254 min
20169456%475%110 min
20172150%0
201810100%10%
20196350%967%45 min
202010100%0
2022010%
2023010%
2024110%0
20254175%3100%54 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.

By product

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

The latest warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Sep 3, 2:22 PM CDTSevere Thunderstorm WarningMPX18 min
Jul 24, 12:59 PM CDTExtreme Heat WarningMPX56 hr
Jul 12, 2:43 AM CDTExtreme Heat WarningMPX6 days
Jun 28, 12:44 AM CDTExtreme Heat WarningMPX47 hr
Jun 19, 4:39 PM CDTSevere Thunderstorm WarningMPX49 min
May 1, 1:03 PM CDTFreeze WarningMPX19 hr
Apr 1, 3:11 AM CDTWinter Storm WarningMPX33 hr
Mar 27, 11:13 AM CDTRed Flag WarningMPX34 hr
Mar 15, 3:07 PM CDTWinter Storm WarningMPX10 hr
Mar 14, 2:36 AM CDTBlizzard WarningMPX52 hr
Mar 13, 9:37 AM CDTWinter Storm WarningMPX28 hr
Mar 11, 10:01 PM CDTHigh Wind WarningMPX33 hr

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.