Alert archive / Mississippi

Weather alerts in Jefferson County, Mississippi

3,441 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Jefferson County and its neighbors

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

Alerts
3,441
Warnings
1,029
Watches
682
Advisories
664
Busiest year
2008240 alerts
Average year
84over 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, 42% of tornado reports in Jefferson County fell inside a tornado warning issued on average 9 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
200811373%1100%3 min
20094250%0
20107186%0
201130100%0
201220100%10%
20134175%0
201510100%0
20165260%0
20176267%367%4 min
2018220%0
20193167%333%0 min
20202150%0
202120100%10%
20224175%1100%33 min
20232150%0
2024110%20%
202530100%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
2008472743%1573%22 min
2009201145%580%32 min
2010221150%667%21 min
2011211433%989%32 min
2012221436%6100%14 min
2013191237%4100%18 min
201414843%580%24 min
2015241538%4100%29 min
2016171229%11100%19 min
2017181139%683%32 min
201816850%2100%39 min
2019262023%8100%18 min
2020191237%1392%29 min
20215420%1100%4 min
2022211148%5100%28 min
2023281546%888%36 min
2024191142%1100%12 min
2025332427%989%27 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200814936%1100%97 min
20095260%0
20109722%1100%104 min
2011330%0
20128363%0
20138538%1100%61 min
201410460%1100%48 min
20154250%0
20167357%0
20174250%0
2018220%0
20192150%0
20206517%6100%113 min
202110100%0
20228275%0
202310100%0
20245420%10%
20255340%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 27, 1:52 AM CDTSevere Thunderstorm WarningJAN53 min
Aug 21, 5:13 PM CDTSevere Thunderstorm Warning Considerable damage threatJAN46 min
Aug 21, 4:14 PM CDTSevere Thunderstorm WarningJAN61 min
Aug 21, 4:10 PM CDTSevere Thunderstorm WarningJAN50 min
Aug 21, 4:04 PM CDTSevere Thunderstorm WarningJAN56 min
Aug 21, 2:38 PM CDTSevere Thunderstorm WarningJAN52 min
Aug 20, 12:46 PM CDTExtreme Heat WarningJAN31 hr
Aug 19, 3:12 AM CDTExtreme Heat WarningJAN18 hr
Aug 16, 2:15 AM CDTExtreme Heat WarningJAN42 hr
Jul 28, 2:00 PM CDTExtreme Heat WarningJAN31 hr
Jul 26, 12:01 PM CDTExtreme Heat WarningJAN57 hr
Jul 21, 1:50 PM CDTExtreme Heat WarningJAN29 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.