Alert archive / Illinois / Lee County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Lee County, Illinois, 2008

34 severe thunderstorm warnings in 2008. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Lee County and its neighbors

Each county as a circle sized by its count in 2008. Tap one for its archive.

Severe Thunderstorm Warnings
34
Busiest month
June12 severe thunderstorm warnings
Busiest day
July 10, 20084 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.

19 of 34 severe thunderstorm warnings covering Lee County in 2008 had a qualifying storm report inside them; 6 of 8 hail, wind and damage reports fell inside a warning, on average 23 minutes after it went out.

Lee County, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings341944%875%23 min

Each office's whole area, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Chicago, IL: severe thunderstorm warnings1808056%37075%31 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
Apr 25, 5:38 PM CDTSevere Thunderstorm WarningLOT37 min
May 13, 4:41 PM CDTSevere Thunderstorm WarningLOT49 min
May 25, 11:25 AM CDTSevere Thunderstorm WarningLOT50 min
May 25, 12:14 PM CDTSevere Thunderstorm WarningLOT46 min
May 26, 1:16 AM CDTSevere Thunderstorm WarningLOT59 min
Jun 5, 7:12 AM CDTSevere Thunderstorm WarningLOT33 min
Jun 7, 3:10 PM CDTSevere Thunderstorm WarningLOT65 min
Jun 8, 10:55 AM CDTSevere Thunderstorm WarningLOT42 min
Jun 8, 11:30 AM CDTSevere Thunderstorm WarningLOT60 min
Jun 8, 10:02 PM CDTSevere Thunderstorm WarningLOT28 min
Jun 8, 10:31 PM CDTSevere Thunderstorm WarningLOT29 min
Jun 12, 11:07 PM CDTSevere Thunderstorm WarningLOT38 min
Jun 12, 11:37 PM CDTSevere Thunderstorm WarningLOT53 min
Jun 12, 11:47 PM CDTSevere Thunderstorm WarningLOT43 min
Jun 15, 6:25 AM CDTSevere Thunderstorm WarningLOT50 min
Jun 15, 6:49 AM CDTSevere Thunderstorm WarningLOT41 min
Jun 28, 3:02 PM CDTSevere Thunderstorm WarningLOT28 min
Jul 7, 10:27 PM CDTSevere Thunderstorm WarningLOT63 min
Jul 7, 10:58 PM CDTSevere Thunderstorm WarningLOT62 min
Jul 10, 12:36 PM CDTSevere Thunderstorm WarningLOT54 min
Jul 10, 1:30 PM CDTSevere Thunderstorm WarningLOT60 min
Jul 10, 2:31 PM CDTSevere Thunderstorm WarningLOT59 min
Jul 10, 6:56 PM CDTSevere Thunderstorm WarningLOT64 min
Jul 12, 4:39 AM CDTSevere Thunderstorm WarningLOT66 min
Jul 19, 10:53 PM CDTSevere Thunderstorm WarningLOT67 min
Jul 19, 11:37 PM CDTSevere Thunderstorm WarningLOT53 min
Jul 31, 12:28 PM CDTSevere Thunderstorm WarningLOT77 min
Jul 31, 1:44 PM CDTSevere Thunderstorm WarningLOT47 min
Aug 4, 6:11 PM CDTSevere Thunderstorm WarningLOT79 min
Aug 4, 6:43 PM CDTSevere Thunderstorm WarningLOT62 min
Aug 4, 7:33 PM CDTSevere Thunderstorm WarningLOT57 min
Aug 5, 4:10 AM CDTSevere Thunderstorm WarningLOT50 min
Sep 13, 4:29 AM CDTSevere Thunderstorm WarningLOT1 min
Dec 27, 12:16 PM CSTSevere Thunderstorm WarningLOT59 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20072009

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.