Alert archive / South Carolina

Weather alerts in Marion County, South Carolina

3,305 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Marion County and its neighbors

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

Alerts
3,305
Warnings
932
Watches
459
Advisories
688
Busiest year
2011218 alerts
Average year
85over 39 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, 0% of tornado reports in Marion County fell inside a tornado warning, and 89% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008110%0
20115180%0
201210100%0
2014010%
201640100%0
201740100%0
20182150%0
201930100%0
20206183%0
202110100%0
202230100%0
202320100%0
202440100%0

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008281546%520%18 min
200919763%6100%24 min
2010161131%333%29 min
2011413515%17100%45 min
2012372143%1688%33 min
2013161319%757%38 min
2014201620%560%10 min
2015181044%6100%33 min
2016252020%1275%15 min
2017191521%933%26 min
20189544%3100%21 min
2019131023%560%21 min
202012742%3100%27 min
20219633%367%10 min
2022281161%786%18 min
2023181233%580%42 min
202415753%683%35 min
2025161413%2100%21 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20158713%7100%100 min
2016440%3100%162 min
201720100%0
20185420%6100%50 min
201910100%0
2020110%1100%24 min
20212150%1100%55 min
20235420%0
20244250%2100%470 min
20253233%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
Sep 11, 4:16 PM EDTSevere Thunderstorm WarningILM26 min
Sep 5, 6:29 PM EDTSevere Thunderstorm WarningILM61 min
Sep 5, 5:44 PM EDTSevere Thunderstorm WarningILM61 min
Sep 5, 5:20 PM EDTSevere Thunderstorm WarningILM40 min
Aug 20, 3:44 PM EDTSevere Thunderstorm WarningILM22 min
Aug 17, 2:22 AM EDTExtreme Heat WarningILM18 hr
Aug 16, 5:59 PM EDTSevere Thunderstorm WarningILM46 min
Aug 16, 5:43 PM EDTSevere Thunderstorm WarningILM62 min
Aug 10, 3:23 PM EDTSevere Thunderstorm WarningILM38 min
Jul 12, 4:44 PM EDTSevere Thunderstorm WarningILM61 min
Jul 11, 4:39 PM EDTSevere Thunderstorm WarningILM38 min
Jul 11, 2:57 PM EDTSevere Thunderstorm WarningILM47 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.