Alert archive / Missouri

Weather alerts in Shannon County, Missouri

3,755 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Shannon County and its neighbors

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

Alerts
3,755
Warnings
1,382
Watches
698
Advisories
688
Busiest year
2008252 alerts
Average year
92over 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, 50% of tornado reports in Shannon County fell inside a tornado warning issued on average 20 minutes before, and 85% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20089278%30%
20099278%1100%5 min
20104175%0
201140100%0
201210100%0
201310100%0
201540100%0
20176183%0
201860100%0
20193167%0
202010100%0
202120100%0
202230100%0
202320100%0
20246350%3100%24 min
202510190%10%
Share of tornado reports inside a tornado warning, by year.

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200823961%1663%20 min
200920765%1457%45 min
201011282%1100%43 min
2011351363%1385%27 min
201215660%5100%26 min
201310280%1100%37 min
201416663%560%12 min
201516944%475%27 min
20169633%3100%29 min
2017231248%1080%25 min
2018372824%2596%21 min
2019241538%7100%25 min
2020191142%1191%17 min
202113377%0
202219574%4100%28 min
2023261350%475%25 min
202422768%933%26 min
2025321359%888%26 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008171041%989%346 min
2009221341%4100%315 min
201012192%10%
2011131115%13100%255 min
201311827%30%
2014110%0
201511827%2100%237 min
20169633%1100%73 min
20175260%10%
20187529%1100%164 min
20197443%1100%174 min
20204325%3100%238 min
202130100%20%
20224325%1100%194 min
20234175%10%
20248450%250%103 min
20254175%1573%201 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 4, 1:30 PM CDTExtreme Heat WarningSGF4 days
Aug 19, 9:51 PM CDTTornado WarningSGF28 min
Aug 19, 9:31 PM CDTSevere Thunderstorm WarningSGF29 min
Aug 19, 9:25 PM CDTTornado WarningSGF35 min
Aug 19, 9:16 PM CDTTornado WarningSGF44 min
Aug 9, 1:04 AM CDTExtreme Heat WarningSGF8 days
Aug 8, 3:00 AM CDTAreal Flood WarningSGF7 hr
Aug 7, 9:30 PM CDTFlash Flood WarningSGF6 hr
Aug 7, 6:40 PM CDTSevere Thunderstorm WarningSGF50 min
Aug 6, 4:57 PM CDTSevere Thunderstorm Warning Considerable damage threatSGF48 min
Jul 31, 9:34 PM CDTSevere Thunderstorm WarningSGF41 min
Jul 31, 8:12 PM CDTSevere Thunderstorm WarningSGF35 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.