Alert archive / Tennessee

Weather alerts in Shelby County, Tennessee

4,826 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Shelby County and its neighbors

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

Alerts
4,826
Warnings
1,667
Watches
677
Advisories
1,248
Busiest year
2011331 alerts
Average year
118over 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, 79% of tornado reports in Shelby County fell inside a tornado warning issued on average 18 minutes before, and 74% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20084325%4100%16 min
20095420%978%17 min
20109278%2100%22 min
201120480%367%24 min
20127271%0
201310100%0
201430100%0
201610100%0
201710100%0
201920100%10%
202010100%0
20214175%0
202230100%0
20235260%0
202410100%0
20256183%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
2008382047%10100%24 min
2009241346%2387%19 min
2010432151%4367%25 min
2011694633%8274%27 min
2012351849%4766%22 min
2013241250%1675%24 min
2014321650%2259%17 min
2015301357%3482%17 min
2016241250%1457%18 min
2017231343%3278%16 min
2018271544%2972%15 min
2019211624%4486%27 min
2020241729%2879%30 min
2021231439%2588%22 min
2022171324%1450%16 min
2023604623%8981%25 min
2024271641%13100%22 min
2025563439%2871%37 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008171324%1688%90 min
2009271930%2696%78 min
2010422345%60100%134 min
2011271448%1275%208 min
20127443%1182%29 min
20139456%1486%52 min
201414657%2291%117 min
201512467%743%51 min
2016291066%1587%35 min
20178188%714%218 min
20186183%1100%10 min
20196267%650%75 min
20202150%1100%28 min
202115940%1173%57 min
20223233%3100%45 min
202310910%1776%48 min
20247443%8100%40 min
2025261927%18100%119 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
Aug 22, 5:24 PM CDTSevere Thunderstorm WarningMEG51 min
Aug 22, 5:14 PM CDTSevere Thunderstorm WarningMEG46 min
Aug 22, 4:28 PM CDTSevere Thunderstorm WarningMEG47 min
Aug 18, 11:41 AM CDTExtreme Heat WarningMEG32 hr
Aug 17, 4:32 PM CDTSevere Thunderstorm WarningMEG58 min
Aug 17, 3:58 PM CDTSevere Thunderstorm WarningMEG62 min
Aug 16, 7:58 PM CDTExtreme Heat WarningMEG24 hr
Aug 12, 4:06 AM CDTExtreme Heat WarningMEG5 days
Jul 25, 11:17 AM CDTExtreme Heat WarningMEG3 days
Jul 19, 11:47 AM CDTExtreme Heat WarningMEG57 hr
Jul 11, 4:00 PM CDTSevere Thunderstorm WarningMEG45 min
Jul 11, 3:40 PM CDTSevere Thunderstorm WarningMEG50 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.