Alert archive / South Carolina

Weather alerts in Barnwell County, South Carolina

3,011 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Barnwell County and its neighbors

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

Alerts
3,011
Warnings
639
Watches
396
Advisories
1,053
Busiest year
2011184 alerts
Average year
73over 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, 100% of tornado reports in Barnwell County fell inside a tornado warning issued on average 13 minutes before, and 54% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20083233%1100%22 min
200930100%0
2011110%0
20176267%2100%2 min
201910100%0
20206433%5100%16 min
202110100%0
20222150%0
202410100%0
2025220%1100%13 min
Share of tornado reports inside a tornado warning, by year.

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008221055%1292%26 min
2009181139%667%21 min
2010261831%11100%19 min
2011342915%1894%19 min
2012231630%1283%27 min
2013181233%1392%20 min
20149544%5100%27 min
2015242017%9100%30 min
201615147%4100%14 min
2017201240%667%9 min
2018181139%8100%24 min
201912925%367%52 min
202011555%633%17 min
20215420%0
2022241729%989%16 min
20238713%4100%30 min
202412833%0
2025171418%4100%44 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20092150%1100%50 min
2013110%3100%11 min
2015110%0
2016220%0
2020220%0
2023110%0
2024770%0
20253233%10%

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 6, 7:36 PM EDTSevere Thunderstorm WarningCAE39 min
Sep 6, 7:16 PM EDTSevere Thunderstorm WarningCAE29 min
Aug 21, 6:01 PM EDTSevere Thunderstorm WarningCAE59 min
Aug 21, 5:44 PM EDTSevere Thunderstorm WarningCAE46 min
Aug 21, 5:06 PM EDTSevere Thunderstorm WarningCAE39 min
Aug 13, 5:58 PM EDTSevere Thunderstorm WarningCAE47 min
Aug 13, 5:33 PM EDTSevere Thunderstorm WarningCAE27 min
Aug 11, 4:08 PM EDTSevere Thunderstorm WarningCAE52 min
Aug 6, 1:18 PM EDTSevere Thunderstorm WarningCAE42 min
Aug 2, 3:20 PM EDTSevere Thunderstorm WarningCAE40 min
Aug 1, 4:42 PM EDTSevere Thunderstorm WarningCAE48 min
Jul 17, 7:55 PM EDTSevere Thunderstorm WarningCAE50 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.