Alert archive / South Carolina

Weather alerts in Horry County, South Carolina

4,586 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Horry County and its neighbors

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

Alerts
4,586
Warnings
1,177
Watches
441
Advisories
1,061
Busiest year
2024287 alerts
Average year
112over 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, 59% of tornado reports in Horry County fell inside a tornado warning issued on average 7 minutes before, and 83% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20084250%1100%12 min
20116267%0
20126183%1100%9 min
201320100%0
201410100%0
201640100%0
20177186%1100%7 min
20189278%450%4 min
201918572%5100%9 min
202010280%729%1 min
202120100%0
202250100%0
20237186%333%4 min
2024110100%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
2008411759%2075%14 min
2009281354%2171%19 min
2010201240%2143%12 min
2011463915%6988%21 min
2012503138%3090%20 min
2013131115%1250%23 min
2014302420%4193%25 min
201517947%1155%32 min
2016302227%2387%17 min
2017251540%1644%9 min
201816944%1450%9 min
2019251156%1771%25 min
2020151033%1681%12 min
202113838%8100%24 min
2022251636%2871%23 min
2023201240%1753%21 min
2024201430%1593%20 min
2025231726%3087%24 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
201510910%16100%209 min
2016660%9100%215 min
20172150%2100%47 min
201811827%1040%83 min
20195260%367%103 min
2020020%
2021110%250%27 min
20229633%1694%50 min
2023660%13100%127 min
20249722%9100%111 min
20257614%580%40 min

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 5, 7:29 PM EDTSevere Thunderstorm WarningILM31 min
Sep 5, 6:29 PM EDTSevere Thunderstorm WarningILM61 min
Sep 5, 5:44 PM EDTSevere Thunderstorm WarningILM61 min
Aug 22, 6:43 PM EDTSevere Thunderstorm WarningILM47 min
Aug 21, 3:11 PM EDTSevere Thunderstorm WarningILM64 min
Aug 17, 2:21 PM EDTExtreme Heat WarningILM30 hr
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 15, 4:21 PM EDTSevere Thunderstorm WarningILM39 min
Aug 10, 3:23 PM EDTSevere Thunderstorm WarningILM38 min
Jul 11, 3:26 PM EDTSevere Thunderstorm WarningILM63 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.