Alert archive / South Carolina / Calhoun County

Weather alerts in Calhoun County, South Carolina, 2021

135 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Calhoun County and its neighbors

Each county as a circle sized by its count in 2021. Tap one for its archive.

Alerts
135
Warnings
30
Watches
10
Advisories
54
Busiest month
June23 alerts
Busiest day
June 15, 20217 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

1 of 1 tornado warnings covering Calhoun County in 2021 had a tornado report inside them.

Calhoun County, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings110%0
Severe thunderstorm warnings11827%8100%6 min
Flash flood warnings20100%0

Each office's whole area, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Columbia, SC: tornado warnings17571%1587%10 min
NWS Columbia, SC: severe thunderstorm warnings805038%15676%16 min
NWS Columbia, SC: flash flood warnings6350%1182%32 min

An office's figures cover every county it serves, including across state lines.

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.

The alerts

Every alert, in the order issued. Times are local, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Dec 31, 10:10 PM ESTDense Fog AdvisoryCAE10 hr
Jan 1, 3:35 PM ESTFlash Flood WatchCAE34 hr
Jan 1, 4:24 PM ESTRiver Flood WarningCAE9 days
Jan 1, 4:24 PM ESTRiver Flood WarningCAE5 days
Jan 1, 6:47 PM ESTAreal Flood AdvisoryCAE3 hr
Jan 1, 10:01 PM ESTSpecial Weather StatementCAE59 min
Jan 13, 3:25 AM ESTDense Fog AdvisoryCAE9 hr
Jan 15, 12:41 PM ESTLake Wind AdvisoryCAE29 hr
Jan 15, 9:18 PM ESTDense Fog AdvisoryCAE7 hr
Jan 28, 12:53 AM ESTLake Wind AdvisoryCAE11 hr
Feb 14, 9:51 AM ESTRiver Flood WarningCAE21 days
Feb 14, 9:51 AM ESTRiver Flood WarningCAE21 days
Feb 17, 2:01 PM ESTFlash Flood WatchCAE41 hr
Feb 18, 2:23 PM ESTAreal Flood AdvisoryCAE3 hr
Feb 22, 8:43 PM ESTDense Fog AdvisoryCAE3 hr
Feb 23, 12:07 AM ESTDense Fog AdvisoryCAE3 hr
Mar 17, 1:06 AM EDTAreal Flood AdvisoryCAE114 min
Mar 18, 11:42 AM EDTTornado WatchSPC6 hr
Mar 19, 10:53 AM EDTRiver Flood WarningCAE3 days
Mar 19, 10:53 AM EDTRiver Flood WarningCAE66 hr
Mar 26, 10:39 AM EDTRiver Flood WarningCAE5 days
Mar 26, 10:39 AM EDTRiver Flood WarningCAE6 days
Mar 26, 1:56 PM EDTMesoscale DiscussionSPC94 min
Mar 27, 2:40 PM EDTLake Wind AdvisoryCAE36 hr
Mar 28, 12:38 PM EDTMesoscale DiscussionSPC3 hr
Mar 28, 3:49 PM EDTSevere Thunderstorm WarningCAE41 min
Mar 31, 2:22 PM EDTMesoscale DiscussionSPC113 min
Mar 31, 6:24 PM EDTMesoscale DiscussionSPC2 hr
Mar 31, 6:56 PM EDTSpecial Weather StatementCAE34 min
Apr 1, 3:02 AM EDTFreeze WarningCAE30 hr
Apr 2, 9:00 AM EDTRiver Flood WarningCAE41 hr
Apr 2, 9:00 AM EDTRiver Flood WarningCAE30 hr
Apr 2, 9:05 AM EDTFreeze WarningCAE24 hr
Apr 3, 2:36 PM EDTFrost AdvisoryCAE17 hr
Apr 20, 2:02 PM EDTFire Weather WatchCAE12 hr
Apr 21, 1:17 AM EDTLake Wind AdvisoryCAE31 hr
Apr 21, 1:37 AM EDTRed Flag WarningCAE18 hr
May 3, 1:25 PM EDTTornado WatchSPC6 hr
May 3, 4:22 PM EDTSevere Thunderstorm WarningCAE23 min
May 3, 4:26 PM EDTMesoscale DiscussionSPC94 min
May 4, 3:52 PM EDTSevere Thunderstorm WarningCAE41 min
May 4, 4:16 PM EDTMesoscale DiscussionSPC119 min
May 4, 4:56 PM EDTSevere Thunderstorm WatchSPC3 hr
May 4, 6:03 PM EDTSevere Thunderstorm WarningCAE57 min
May 7, 3:09 AM EDTLake Wind AdvisoryCAE17 hr
May 9, 4:08 AM EDTLake Wind AdvisoryCAE15 hr
Jun 7, 4:02 PM EDTSpecial Weather StatementCAE28 min
Jun 7, 4:28 PM EDTSpecial Weather StatementCAE32 min
Jun 9, 5:18 PM EDTSpecial Weather StatementCAE27 min
Jun 9, 6:47 PM EDTSpecial Weather StatementCAE28 min
Jun 9, 6:55 PM EDTSpecial Weather StatementCAE35 min
Jun 9, 7:47 PM EDTAreal Flood AdvisoryCAE58 min
Jun 12, 1:14 PM EDTMesoscale DiscussionSPC3 hr
Jun 12, 4:40 PM EDTSpecial Weather StatementCAE35 min
Jun 12, 5:08 PM EDTSpecial Weather StatementCAE37 min
Jun 14, 9:27 PM EDTSevere Thunderstorm WarningCAE48 min
Jun 15, 12:57 PM EDTMesoscale DiscussionSPC63 min
Jun 15, 1:58 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 15, 4:09 PM EDTMesoscale DiscussionSPC96 min
Jun 15, 5:47 PM EDTSpecial Weather StatementCAE43 min
Jun 15, 5:59 PM EDTSevere Thunderstorm WarningCAE31 min
Jun 15, 6:27 PM EDTSevere Thunderstorm WarningCAE48 min
Jun 19, 2:34 PM EDTSpecial Weather StatementCAE26 min
Jun 20, 2:03 AM EDTFlash Flood WatchCAE17 hr
Jun 20, 2:43 PM EDTMesoscale DiscussionSPC92 min
Jun 20, 3:13 PM EDTSpecial Weather StatementCAE47 min
Jun 20, 4:04 PM EDTFlash Flood WarningCAE3 hr
Jun 20, 4:34 PM EDTSpecial Weather StatementCAE41 min
Jun 28, 11:34 AM EDTLake Wind AdvisoryCAE16 hr
Jul 2, 7:18 PM EDTAreal Flood AdvisoryCAE117 min
Jul 7, 1:14 PM EDTLake Wind AdvisoryCAE23 hr
Jul 8, 1:53 AM EDTAreal Flood AdvisoryCAE3 hr
Jul 8, 2:10 AM EDTSevere Thunderstorm WarningCAE35 min
Jul 8, 3:20 AM EDTSevere Thunderstorm WarningCAE25 min
Jul 9, 4:32 PM EDTSpecial Weather StatementCAE43 min
Jul 16, 4:39 PM EDTAreal Flood AdvisoryCAE2 hr
Jul 17, 1:25 PM EDTAreal Flood AdvisoryCAE65 min
Jul 17, 2:14 PM EDTSpecial Weather StatementCAE46 min
Jul 17, 6:06 PM EDTAreal Flood AdvisoryCAE54 min
Jul 18, 2:06 PM EDTSpecial Weather StatementCAE24 min
Jul 18, 2:35 PM EDTSpecial Weather StatementCAE25 min
Jul 18, 2:50 PM EDTSevere Thunderstorm WarningCAE25 min
Jul 19, 8:14 PM EDTAreal Flood AdvisoryCAE2 hr
Jul 19, 9:02 PM EDTAreal Flood AdvisoryCAE3 hr
Jul 29, 2:44 PM EDTHeat AdvisoryCAE29 hr
Jul 31, 1:40 PM EDTMesoscale DiscussionSPC2 hr
Jul 31, 5:58 PM EDTSpecial Weather StatementCAE32 min
Jul 31, 6:13 PM EDTSevere Thunderstorm WarningCAE47 min
Jul 31, 6:35 PM EDTSpecial Weather StatementCAE25 min
Aug 3, 7:37 AM EDTAreal Flood AdvisoryCAE113 min
Aug 3, 8:28 AM EDTAreal Flood AdvisoryCAE62 min
Aug 3, 9:32 AM EDTAreal Flood AdvisoryCAE118 min
Aug 7, 9:37 PM EDTSpecial Weather StatementCAE23 min
Aug 7, 9:49 PM EDTAreal Flood AdvisoryCAE116 min
Aug 11, 2:17 PM EDTSpecial Weather StatementCAE28 min
Aug 16, 1:20 PM EDTSpecial Weather StatementCAE40 min
Aug 16, 2:43 PM EDTAreal Flood AdvisoryCAE62 min
Aug 17, 10:42 AM EDTTornado WatchSPC8 hr
Aug 17, 5:29 PM EDTAreal Flood AdvisoryCAE3 hr
Aug 17, 5:29 PM EDTTornado WarningCAE46 min
Aug 17, 10:58 PM EDTAreal Flood AdvisoryCAE2 hr
Aug 19, 6:48 PM EDTAreal Flood AdvisoryCAE117 min
Aug 19, 7:35 PM EDTSpecial Weather StatementCAE25 min
Aug 22, 11:10 AM EDTAreal Flood AdvisoryCAE110 min
Aug 22, 2:41 PM EDTAreal Flood AdvisoryCAE3 hr
Aug 22, 3:39 PM EDTFlash Flood Warning Considerable damage threatCAE111 min
Aug 22, 4:55 PM EDTAreal Flood AdvisoryCAE103 min
Aug 23, 3:45 AM EDTDense Fog AdvisoryCAE5 hr
Aug 31, 3:24 PM EDTSpecial Weather StatementCAE36 min
Aug 31, 4:37 PM EDTSpecial Weather StatementCAE23 min
Sep 15, 4:14 PM EDTSpecial Weather StatementCAE31 min
Sep 22, 2:44 PM EDTMesoscale DiscussionSPC3 hr
Sep 22, 5:38 PM EDTSpecial Weather StatementCAE22 min
Oct 8, 10:15 PM EDTRiver Flood WarningCAE4 days
Oct 8, 10:17 PM EDTRiver Flood WarningCAE3 days
Oct 16, 4:06 AM EDTLake Wind AdvisoryCAE28 hr
Nov 5, 2:27 PM EDTLake Wind AdvisoryCAE45 hr
Nov 13, 3:40 AM ESTFrost AdvisoryCAE29 hr
Nov 15, 10:46 AM ESTFrost AdvisoryCAE22 hr
Nov 19, 12:52 AM ESTLake Wind AdvisoryCAE10 hr
Nov 19, 3:39 AM ESTFrost AdvisoryCAE28 hr
Nov 22, 2:26 AM ESTFreeze WatchCAE25 hr
Nov 22, 4:20 PM ESTLake Wind AdvisoryCAE15 hr
Nov 23, 3:47 AM ESTFreeze WarningCAE29 hr
Dec 5, 3:27 AM ESTDense Fog AdvisoryCAE7 hr
Dec 6, 1:33 AM ESTDense Fog AdvisoryCAE7 hr
Dec 8, 10:10 PM ESTDense Fog AdvisoryCAE11 hr
Dec 10, 7:35 PM ESTDense Fog AdvisoryCAE13 hr
Dec 11, 7:25 PM ESTSpecial Weather StatementCAE35 min
Dec 16, 9:33 PM ESTDense Fog AdvisoryCAE12 hr
Dec 17, 9:36 PM ESTDense Fog AdvisoryCAE12 hr
Dec 19, 1:51 PM ESTLake Wind AdvisoryCAE8 hr
Dec 24, 8:18 PM ESTLake Wind AdvisoryCAE23 hr
Dec 27, 3:29 AM ESTDense Fog AdvisoryCAE7 hr
Dec 30, 1:04 PM ESTSpecial Weather StatementCAE41 min

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20202022

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.