Alert archive / Illinois / Williamson County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Williamson County, Illinois, 2023

47 severe thunderstorm warnings in 2023. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Williamson County and its neighbors

Each county as a circle sized by its count in 2023. Tap one for its archive.

Severe Thunderstorm Warnings
47
Busiest month
July21 severe thunderstorm warnings
Busiest day
June 30, 20236 severe thunderstorm warnings

Over time

By month

Warning verification

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

28 of 47 severe thunderstorm warnings covering Williamson County in 2023 had a qualifying storm report inside them; 27 of 32 hail, wind and damage reports fell inside a warning, on average 18 minutes after it went out.

Williamson County, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings472840%3284%18 min

Each office's whole area, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Paducah, KY: severe thunderstorm warnings49522754%54479%21 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, Central Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Feb 9, 3:26 AM CSTSevere Thunderstorm WarningPAH39 min
Feb 22, 3:08 PM CSTSevere Thunderstorm WarningPAH37 min
Mar 23, 10:40 PM CDTSevere Thunderstorm WarningPAH35 min
Mar 31, 9:30 PM CDTSevere Thunderstorm WarningPAH45 min
Apr 5, 4:18 AM CDTSevere Thunderstorm WarningPAH42 min
Apr 5, 4:57 AM CDTSevere Thunderstorm WarningPAH15 min
Apr 5, 12:17 PM CDTSevere Thunderstorm WarningPAH28 min
Apr 15, 8:32 PM CDTSevere Thunderstorm WarningPAH43 min
Apr 15, 9:23 PM CDTSevere Thunderstorm WarningPAH52 min
May 7, 9:04 AM CDTSevere Thunderstorm WarningPAH26 min
May 7, 9:28 AM CDTSevere Thunderstorm WarningPAH30 min
May 7, 1:47 PM CDTSevere Thunderstorm WarningPAH43 min
May 7, 2:26 PM CDTSevere Thunderstorm WarningPAH49 min
Jun 29, 3:26 PM CDTSevere Thunderstorm WarningPAH34 min
Jun 30, 4:57 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH48 min
Jun 30, 5:21 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH24 min
Jun 30, 5:33 PM CDTSevere Thunderstorm WarningPAH27 min
Jun 30, 6:06 PM CDTSevere Thunderstorm WarningPAH39 min
Jun 30, 6:41 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH37 min
Jun 30, 6:59 PM CDTSevere Thunderstorm WarningPAH30 min
Jun 30, 7:58 PM CDTSevere Thunderstorm WarningPAH32 min
Jul 1, 3:29 PM CDTSevere Thunderstorm WarningPAH46 min
Jul 1, 4:20 PM CDTSevere Thunderstorm WarningPAH40 min
Jul 1, 5:37 PM CDTSevere Thunderstorm WarningPAH38 min
Jul 1, 5:39 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH51 min
Jul 2, 1:05 PM CDTSevere Thunderstorm WarningPAH40 min
Jul 2, 1:14 PM CDTSevere Thunderstorm WarningPAH46 min
Jul 2, 1:21 PM CDTSevere Thunderstorm WarningPAH39 min
Jul 2, 1:43 PM CDTSevere Thunderstorm WarningPAH47 min
Jul 2, 2:10 PM CDTSevere Thunderstorm WarningPAH35 min
Jul 2, 2:52 PM CDTSevere Thunderstorm WarningPAH38 min
Jul 16, 5:53 PM CDTSevere Thunderstorm WarningPAH37 min
Jul 18, 12:17 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH43 min
Jul 19, 4:15 AM CDTSevere Thunderstorm WarningPAH45 min
Jul 19, 5:48 AM CDTSevere Thunderstorm WarningPAH30 min
Jul 24, 4:35 AM CDTSevere Thunderstorm WarningPAH40 min
Jul 24, 5:06 AM CDTSevere Thunderstorm WarningPAH23 min
Jul 29, 5:15 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH60 min
Jul 29, 5:40 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH50 min
Jul 29, 6:01 PM CDTSevere Thunderstorm WarningPAH44 min
Jul 29, 6:14 PM CDTSevere Thunderstorm WarningPAH16 min
Aug 2, 11:53 PM CDTSevere Thunderstorm Warning Considerable damage threatPAH52 min
Aug 3, 12:29 AM CDTSevere Thunderstorm WarningPAH46 min
Aug 6, 11:57 PM CDTSevere Thunderstorm WarningPAH33 min
Aug 7, 12:21 AM CDTSevere Thunderstorm WarningPAH39 min
Aug 7, 12:48 AM CDTSevere Thunderstorm WarningPAH42 min
Sep 27, 7:27 PM CDTSevere Thunderstorm WarningPAH48 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20222024

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.