Alert archive / Illinois / Saint Clair County

Weather alerts in Saint Clair County, Illinois, 2023

133 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Saint Clair County and its neighbors

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

Alerts
133
Warnings
54
Watches
24
Advisories
20
Busiest month
July39 alerts
Busiest day
April 15, 202310 alerts

Over time

By month

Warning verification

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

3 of 4 tornado warnings covering Saint Clair County in 2023 had a tornado report inside them; 2 of 2 tornado reports fell inside a warning, on average 29 minutes after it went out.

Saint Clair County, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings4325%2100%29 min
Severe thunderstorm warnings402732%8685%24 min
Flash flood warnings330%250%61 min

Each office's whole area, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS St. Louis, MO: tornado warnings33876%2576%11 min
NWS St. Louis, MO: severe thunderstorm warnings38021843%1,08284%22 min
NWS St. Louis, MO: flash flood warnings382242%4477%100 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
Jan 1, 11:43 PM CSTDense Fog AdvisoryLSX15 hr
Jan 3, 2:06 PM CSTMesoscale DiscussionSPC2 hr
Jan 22, 2:06 PM CSTWinter Storm WatchLSX24 hr
Jan 23, 2:12 PM CSTWinter Storm WarningLSX43 hr
Jan 24, 11:44 PM CSTMesoscale DiscussionSPC6 hr
Jan 29, 1:30 PM CSTWinter Weather AdvisoryLSX20 hr
Feb 8, 2:04 AM CSTWind AdvisoryLSX34 hr
Feb 13, 2:12 PM CSTWind AdvisoryLSX30 hr
Feb 22, 12:04 PM CSTMesoscale DiscussionSPC56 min
Feb 22, 12:20 PM CSTTornado WatchSPC5 hr
Feb 22, 2:01 PM CSTSevere Thunderstorm WarningLSX59 min
Feb 22, 2:26 PM CSTSevere Thunderstorm WarningLSX64 min
Feb 22, 2:27 PM CSTMesoscale DiscussionSPC2 hr
Feb 26, 1:27 AM CSTWind AdvisoryLSX41 hr
Feb 27, 1:43 AM CSTMesoscale DiscussionSPC62 min
Mar 1, 1:36 PM CSTFlood WatchLSX46 hr
Mar 2, 2:42 AM CSTWind AdvisoryLSX39 hr
Mar 22, 1:39 PM CDTFlood WatchLSX54 hr
Mar 30, 3:03 AM CDTWind AdvisoryLSX58 hr
Mar 31, 8:36 AM CDTMesoscale DiscussionSPC84 min
Mar 31, 12:28 PM CDTTornado Watch PDSSPC11 hr
Mar 31, 12:53 PM CDTMesoscale DiscussionSPC97 min
Mar 31, 6:28 PM CDTSevere Thunderstorm WarningLSX47 min
Mar 31, 7:36 PM CDTSevere Thunderstorm WarningLSX39 min
Mar 31, 7:38 PM CDTSevere Thunderstorm WarningLSX52 min
Apr 3, 2:28 PM CDTWind AdvisoryLSX41 hr
Apr 5, 2:27 AM CDTSevere Thunderstorm WatchSPC10 hr
Apr 5, 8:00 AM CDTSevere Thunderstorm WarningLSX45 min
Apr 5, 9:11 AM CDTSevere Thunderstorm WarningLSX26 min
Apr 15, 8:50 AM CDTMesoscale DiscussionSPC85 min
Apr 15, 11:39 AM CDTMesoscale DiscussionSPC3 hr
Apr 15, 3:21 PM CDTMesoscale DiscussionSPC114 min
Apr 15, 4:03 PM CDTTornado WatchSPC6 hr
Apr 15, 5:07 PM CDTMesoscale DiscussionSPC83 min
Apr 15, 6:19 PM CDTTornado WarningLSX41 min
Apr 15, 6:27 PM CDTSevere Thunderstorm WarningLSX52 min
Apr 15, 6:34 PM CDTTornado WarningLSX41 min
Apr 15, 6:39 PM CDTTornado WarningLSX51 min
Apr 15, 6:50 PM CDTMesoscale DiscussionSPC85 min
Apr 15, 7:09 PM CDTTornado WarningLSX51 min
Apr 20, 1:20 PM CDTSevere Thunderstorm WatchSPC7 hr
Apr 20, 3:10 PM CDTMesoscale DiscussionSPC95 min
Apr 20, 5:36 PM CDTMesoscale DiscussionSPC84 min
Apr 22, 3:57 AM CDTFrost AdvisoryLSX29 hr
Apr 23, 2:41 AM CDTFrost AdvisoryLSX29 hr
Apr 23, 2:41 AM CDTFreeze WarningLSX29 hr
May 7, 1:00 PM CDTMesoscale DiscussionSPC2 hr
May 7, 1:18 PM CDTSevere Thunderstorm WatchSPC10 hr
May 7, 4:51 PM CDTSevere Thunderstorm WarningLSX39 min
May 7, 5:20 PM CDTSevere Thunderstorm WarningLSX40 min
May 7, 5:59 PM CDTSevere Thunderstorm WarningLSX20 min
May 7, 6:10 PM CDTMesoscale DiscussionSPC2 hr
May 8, 2:16 PM CDTMesoscale DiscussionSPC59 min
May 8, 3:19 PM CDTSevere Thunderstorm WatchSPC10 hr
May 8, 10:05 PM CDTSevere Thunderstorm WarningLSX40 min
May 13, 12:24 PM CDTSevere Thunderstorm WatchSPC7 hr
May 13, 2:38 PM CDTMesoscale DiscussionSPC2 hr
May 13, 2:49 PM CDTSevere Thunderstorm WarningLSX41 min
May 13, 3:26 PM CDTSevere Thunderstorm WarningLSX49 min
May 13, 3:30 PM CDTSevere Thunderstorm WarningLSX19 min
May 13, 6:09 PM CDTMesoscale DiscussionSPC2 hr
May 14, 12:43 PM CDTMesoscale DiscussionSPC3 hr
May 14, 2:59 PM CDTSevere Thunderstorm WatchSPC7 hr
May 14, 5:11 PM CDTAreal Flood AdvisoryLSX3 hr
May 14, 5:20 PM CDTSevere Thunderstorm WarningLSX40 min
May 14, 5:47 PM CDTMesoscale DiscussionSPC88 min
May 14, 5:56 PM CDTFlash Flood WarningLSX4 hr
May 15, 2:07 PM CDTFlood WatchLSX16 hr
Jun 18, 5:22 PM CDTAreal Flood AdvisoryLSX15 min
Jun 18, 5:37 PM CDTFlash Flood WarningLSX3 hr
Jun 28, 3:02 AM CDTHeat AdvisoryLSX64 hr
Jun 30, 2:32 PM CDTMesoscale DiscussionSPC2 hr
Jun 30, 3:53 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 30, 6:07 PM CDTSevere Thunderstorm WarningLSX11 min
Jun 30, 6:31 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX59 min
Jun 30, 7:11 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX49 min
Jun 30, 7:58 PM CDTMesoscale DiscussionSPC92 min
Jun 30, 9:30 PM CDTSevere Thunderstorm WarningLSX45 min
Jul 1, 12:04 PM CDTSevere Thunderstorm WatchSPC9 hr
Jul 1, 2:15 PM CDTMesoscale DiscussionSPC90 min
Jul 1, 3:39 PM CDTSevere Thunderstorm WarningLSX21 min
Jul 1, 3:58 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX47 min
Jul 1, 4:00 PM CDTSevere Thunderstorm WarningLSX38 min
Jul 1, 4:34 PM CDTSevere Thunderstorm WarningLSX41 min
Jul 2, 12:45 AM CDTSevere Thunderstorm WarningLSX45 min
Jul 5, 1:07 PM CDTMesoscale DiscussionSPC2 hr
Jul 5, 2:18 PM CDTSevere Thunderstorm WarningLSX30 min
Jul 5, 2:36 PM CDTSevere Thunderstorm WarningLSX21 min
Jul 5, 3:29 PM CDTAreal Flood AdvisoryLSX88 min
Jul 12, 4:59 PM CDTMesoscale DiscussionSPC91 min
Jul 14, 1:13 PM CDTSevere Thunderstorm WarningLSX14 min
Jul 14, 8:40 PM CDTSevere Thunderstorm WarningLSX36 min
Jul 14, 9:11 PM CDTAreal Flood AdvisoryLSX3 hr
Jul 14, 9:29 PM CDTFlash Flood WarningLSX4 hr
Jul 16, 2:21 PM CDTSevere Thunderstorm WatchSPC4 hr
Jul 16, 3:33 PM CDTSevere Thunderstorm WarningLSX30 min
Jul 16, 4:00 PM CDTMesoscale DiscussionSPC90 min
Jul 17, 1:28 PM CDTSevere Thunderstorm WatchSPC8 hr
Jul 17, 2:41 PM CDTMesoscale DiscussionSPC2 hr
Jul 17, 2:57 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX48 min
Jul 17, 3:17 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX32 min
Jul 18, 11:41 PM CDTMesoscale DiscussionSPC2 hr
Jul 19, 3:55 AM CDTSevere Thunderstorm WatchSPC6 hr
Jul 20, 8:58 AM CDTMesoscale DiscussionSPC92 min
Jul 20, 11:12 AM CDTSevere Thunderstorm WarningLSX34 min
Jul 25, 1:09 PM CDTHeat AdvisoryLSX4 days
Jul 26, 11:59 AM CDTMesoscale DiscussionSPC2 hr
Jul 27, 3:05 AM CDTExcessive Heat WarningLSX62 hr
Jul 29, 11:28 AM CDTSevere Thunderstorm WatchSPC7 hr
Jul 29, 2:18 PM CDTMesoscale DiscussionSPC117 min
Jul 29, 3:24 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX36 min
Jul 29, 3:57 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX48 min
Jul 29, 4:16 PM CDTSevere Thunderstorm Warning Destructive damage threatLSX44 min
Jul 29, 4:47 PM CDTSevere Thunderstorm Warning Considerable damage threatLSX58 min
Aug 2, 2:56 AM CDTFlood WatchLSX31 hr
Aug 2, 7:58 PM CDTSevere Thunderstorm WatchSPC7 hr
Aug 6, 3:16 PM CDTTornado WatchSPC9 hr
Aug 10, 1:05 AM CDTDense Fog AdvisoryLSX8 hr
Aug 12, 1:42 AM CDTSevere Thunderstorm WatchSPC5 hr
Aug 12, 2:56 AM CDTMesoscale DiscussionSPC94 min
Aug 12, 4:46 AM CDTSevere Thunderstorm WarningLSX59 min
Aug 12, 5:16 AM CDTMesoscale DiscussionSPC89 min
Aug 18, 2:51 AM CDTExcessive Heat WatchLSX25 hr
Aug 19, 3:24 AM CDTExcessive Heat WarningLSX7 days
Aug 22, 3:27 AM CDTDense Fog AdvisoryLSX5 hr
Aug 23, 4:50 AM CDTDense Fog AdvisoryLSX3 hr
Aug 25, 4:17 PM CDTSevere Thunderstorm WarningLSX31 min
Sep 27, 12:31 AM CDTSevere Thunderstorm WarningLSX20 min
Oct 21, 3:05 AM CDTRed Flag WarningLSX16 hr
Oct 27, 4:16 PM CDTMesoscale DiscussionSPC89 min
Oct 28, 2:16 PM CDTFreeze WarningLSX44 hr
Oct 30, 9:57 AM CDTFreeze WarningLSX24 hr
Dec 24, 1:19 AM CSTDense Fog AdvisoryLSX8 hr

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 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.