Alert archive / Tennessee

Weather alerts in Lewis County, Tennessee

3,029 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Lewis County and its neighbors

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

Alerts
3,029
Warnings
745
Watches
566
Advisories
700
Busiest year
2011175 alerts
Average year
84over 36 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, 86% of tornado reports in Lewis County fell inside a tornado warning issued on average 16 minutes before, and 71% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20084250%2100%23 min
20093233%2100%4 min
20109189%0
201150100%0
201220100%0
20133233%0
201410100%0
20153167%0
20162150%1100%31 min
20175340%1100%11 min
20183233%0
202010100%0
20215180%0
202320100%0
20244175%0
202514379%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
20086350%475%12 min
200915380%20%
201029679%250%11 min
2011392438%786%17 min
201213838%560%21 min
20137614%4100%32 min
201415940%367%37 min
20154175%1100%23 min
20169544%20%
201710910%1050%17 min
20187614%333%5 min
20197443%250%49 min
2020211529%580%22 min
202119858%2100%9 min
20228713%1100%18 min
2023211433%6100%19 min
20247614%683%38 min
2025271352%367%33 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008110%0
20098188%0
20103167%10%
20118450%0
20132150%0
20147529%4100%167 min
20152150%0
2017550%0
20183233%0
20196350%1100%78 min
2020330%0
202110910%0
20258188%0

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 20, 4:15 AM CDTFlash Flood WarningOHX4 hr
Aug 14, 10:49 AM CDTExtreme Heat WarningOHX56 hr
Aug 8, 3:58 PM CDTSevere Thunderstorm WarningOHX47 min
Aug 8, 3:44 PM CDTFlash Flood WarningOHX3 hr
Jul 26, 11:09 PM CDTSevere Thunderstorm WarningOHX21 min
Jul 26, 10:32 PM CDTExtreme Heat WarningOHX45 hr
Jul 22, 12:49 AM CDTFlash Flood Warning Considerable damage threatOHX3 hr
Jul 21, 10:43 PM CDTFlash Flood WarningOHX5 hr
Jul 11, 3:15 PM CDTSevere Thunderstorm WarningOHX45 min
Jul 1, 6:28 PM CDTSevere Thunderstorm WarningOHX47 min
Jun 28, 11:51 AM CDTExtreme Heat WarningOHX5 days
Apr 28, 3:16 AM CDTSevere Thunderstorm WarningOHX44 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.