Alert archive / South Carolina
Flash Flood Warnings in South Carolina
1,370 flash flood warnings since 1986. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of flash flood warnings reaches back to 1986.
Flash Flood Warnings by county
Each county as a circle sized by its count since 1986. Tap one for its archive.
- Flash Flood Warnings
- 1,370
- Busiest year
- 2024116 flash flood warnings
- Average year
- 35over 39 years on file
Over time
By year
Before October 2007 these were issued for whole counties, and a storm crossing three counties was often three warnings; since then one polygon follows the storm. The count changed with the practice, not only with 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, 87% of flash flood reports in South Carolina fell inside a flash flood warning issued on average 148 minutes before, and 32% of the flash flood warnings had no report inside them.
Flash flood warnings by year
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| 2008 | 27 | 16 | 41% | 51 | 84% | 81 min |
| 2009 | 41 | 26 | 37% | 70 | 84% | 65 min |
| 2010 | 39 | 26 | 33% | 51 | 82% | 74 min |
| 2011 | 25 | 9 | 64% | 19 | 74% | 33 min |
| 2012 | 28 | 19 | 32% | 70 | 87% | 92 min |
| 2013 | 81 | 60 | 26% | 212 | 89% | 84 min |
| 2014 | 61 | 41 | 33% | 115 | 87% | 69 min |
| 2015 | 91 | 74 | 19% | 399 | 93% | 297 min |
| 2016 | 37 | 32 | 14% | 137 | 86% | 141 min |
| 2017 | 38 | 21 | 45% | 49 | 96% | 55 min |
| 2018 | 37 | 28 | 24% | 88 | 86% | 121 min |
| 2019 | 18 | 12 | 33% | 19 | 74% | 132 min |
| 2020 | 44 | 31 | 30% | 105 | 78% | 99 min |
| 2021 | 21 | 11 | 48% | 33 | 61% | 42 min |
| 2022 | 47 | 25 | 47% | 73 | 84% | 91 min |
| 2023 | 35 | 25 | 29% | 53 | 83% | 105 min |
| 2024 | 116 | 75 | 35% | 225 | 90% | 195 min |
| 2025 | 54 | 37 | 31% | 134 | 90% | 67 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 county
Every county with at least one alert. A county page lists each alert that covered it.
- Richland County196
- Charleston County187
- Greenville County153
- Berkeley County147
- Lexington County111
- Horry County97
- Spartanburg County89
- Dorchester County76
- Pickens County71
- Anderson County65
- Georgetown County64
- Oconee County62
- Beaufort County61
- Orangeburg County59
- Colleton County57
- Jasper County55
- Sumter County47
- Calhoun County46
- York County46
- Clarendon County45
- Aiken County44
- Kershaw County44
- Marion County43
- Laurens County39
- Chesterfield County37
- Lancaster County36
- Dillon County33
- Florence County32
- Greenwood County32
- Cherokee County31
- Union County29
- Hampton County29
- Williamsburg County29
- Abbeville County28
- Edgefield County28
- Bamberg County27
- Marlboro County26
- McCormick County24
- Fairfield County24
- Lee County23
The latest flash flood warnings
The most recent on file, newest first.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 11, 4:28 PM EDT | Flash Flood Warning | CHS | Charleston, Colleton | 2 hr |
| Aug 27, 9:19 PM EDT | Flash Flood Warning | CAE | Lancaster | 3 hr |
| Aug 27, 6:22 PM EDT | Flash Flood Warning | CHS | Beaufort, Colleton, Hampton | 2 hr |
| Aug 27, 3:16 PM EDT | Flash Flood Warning | CAE | Aiken, Edgefield | 87 min |
| Aug 22, 6:30 PM EDT | Flash Flood Warning | CHS | Berkeley, Charleston | 3 hr |
| Aug 22, 5:24 PM EDT | Flash Flood Warning | CHS | Berkeley, Charleston, Dorchester | 5 hr |
| Aug 21, 7:13 PM EDT | Flash Flood Warning | CAE | Clarendon, Orangeburg | 3 hr |
| Aug 16, 5:38 PM EDT | Flash Flood Warning | ILM | Florence | 65 min |
| Aug 13, 7:30 PM EDT | Flash Flood Warning | CHS | Dorchester | 80 min |
| Aug 12, 11:45 PM EDT | Flash Flood Warning | GSP | Spartanburg, Union | 2 hr |
| Aug 10, 3:32 PM EDT | Flash Flood Warning | CAE | Kershaw, Richland | 91 min |
| Aug 6, 4:30 PM EDT | Flash Flood Warning | CAE | Lexington, Newberry, Saluda | 2 hr |
Nearby
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.