Alert archive / South Carolina

Weather alerts in Florence County, South Carolina

3,438 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Florence County and its neighbors

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

Alerts
3,438
Warnings
1,007
Watches
445
Advisories
751
Busiest year
2011226 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, 67% of tornado reports in Florence County fell inside a tornado warning issued on average 4 minutes before, and 86% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008110%2100%3 min
200920100%0
20102150%0
201140100%0
201620100%0
201710100%0
201820100%0
20193167%1100%2 min
20204175%333%7 min
202240100%0
202430100%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
2008211433%1173%24 min
2009221055%1080%25 min
2010181233%10100%22 min
2011403220%4185%35 min
2012362336%3382%24 min
2013161038%1856%15 min
201412118%1377%20 min
2015242017%1878%23 min
2016353014%2492%22 min
2017211529%1155%19 min
20189633%978%19 min
201913931%1283%19 min
2020171135%786%18 min
202110640%475%14 min
2022281257%1182%20 min
20239633%2100%20 min
2024161038%1369%21 min
2025141029%1070%26 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2012110%3100%57 min
20158713%5100%283 min
2016220%978%200 min
201710100%0
20185420%1100%119 min
2020220%1191%86 min
2021110%0
20232150%0
2024330%888%249 min
202510100%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 6, 3:51 PM EDTSevere Thunderstorm WarningILM39 min
Sep 5, 4:46 PM EDTSevere Thunderstorm WarningILM44 min
Aug 21, 6:13 PM EDTSevere Thunderstorm WarningILM62 min
Aug 21, 2:35 PM EDTSevere Thunderstorm WarningILM55 min
Aug 21, 2:11 PM EDTSevere Thunderstorm WarningILM49 min
Aug 17, 2:22 AM EDTExtreme Heat WarningILM18 hr
Aug 16, 5:43 PM EDTSevere Thunderstorm WarningILM62 min
Aug 16, 5:38 PM EDTFlash Flood WarningILM65 min
Aug 10, 4:05 PM EDTSevere Thunderstorm WarningILM41 min
Jul 12, 4:52 PM EDTSevere Thunderstorm WarningILM26 min
Jul 12, 4:44 PM EDTSevere Thunderstorm WarningILM61 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.