Alert archive / Illinois / Perry County

Weather alerts in Perry County, Illinois, 2020

100 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Perry County and its neighbors

Each county as a circle sized by its count in 2020. Tap one for its archive.

Alerts
100
Warnings
24
Watches
17
Advisories
34
Busiest month
April18 alerts
Busiest day
March 12, 20206 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 Perry County in 2020 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 12 minutes after it went out.

Perry County, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings110%1100%12 min
Severe thunderstorm warnings10730%1593%26 min
Flash flood warnings6517%4100%125 min

Each office's whole area, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Paducah, KY: tornado warnings451469%3355%13 min
NWS Paducah, KY: severe thunderstorm warnings1778254%29672%23 min
NWS Paducah, KY: flash flood warnings1065845%9589%102 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 8, 2:59 PM CSTFlash Flood WatchPAH3 days
Jan 10, 2:47 AM CSTWind AdvisoryPAH39 hr
Jan 11, 2:01 AM CSTFlash Flood WarningPAH9 hr
Jan 11, 11:26 AM CSTAreal Flood WarningPAH12 hr
Jan 16, 2:52 PM CSTWinter Weather AdvisoryPAH22 hr
Jan 29, 7:19 AM CSTWinter Weather AdvisoryPAH4 hr
Feb 11, 10:28 AM CSTFlash Flood WatchPAH34 hr
Mar 12, 2:39 AM CDTDense Fog AdvisoryPAH7 hr
Mar 12, 11:44 AM CDTTornado WatchSPC6 hr
Mar 12, 1:00 PM CDTSevere Thunderstorm WarningPAH45 min
Mar 12, 1:28 PM CDTMesoscale DiscussionSPC2 hr
Mar 12, 1:39 PM CDTSevere Thunderstorm WarningPAH51 min
Mar 12, 1:46 PM CDTAreal Flood AdvisoryPAH2 hr
Mar 19, 2:36 AM CDTFlash Flood WatchPAH25 hr
Mar 19, 3:09 PM CDTSpecial Weather StatementPAH51 min
Mar 19, 3:27 PM CDTSevere Thunderstorm WarningPAH48 min
Mar 19, 3:32 PM CDTTornado WarningPAH43 min
Mar 19, 3:53 PM CDTFlash Flood WarningPAH3 hr
Mar 25, 3:32 AM CDTDense Fog AdvisoryPAH5 hr
Mar 27, 8:02 PM CDTMesoscale DiscussionSPC88 min
Mar 27, 8:11 PM CDTSpecial Weather StatementPAH19 min
Mar 28, 1:17 PM CDTMesoscale DiscussionSPC88 min
Mar 28, 3:53 PM CDTTornado WatchSPC5 hr
Apr 6, 6:20 AM CDTDense Fog AdvisoryPAH3 hr
Apr 8, 3:45 PM CDTMesoscale DiscussionSPC2 hr
Apr 8, 4:24 PM CDTTornado WatchSPC7 hr
Apr 8, 5:16 PM CDTSpecial Weather StatementPAH44 min
Apr 8, 5:26 PM CDTSevere Thunderstorm WarningPAH49 min
Apr 8, 5:59 PM CDTSevere Thunderstorm WarningPAH46 min
Apr 8, 6:15 PM CDTSevere Thunderstorm WarningPAH32 min
Apr 8, 7:46 PM CDTMesoscale DiscussionSPC119 min
Apr 12, 3:21 AM CDTWind AdvisoryPAH31 hr
Apr 13, 5:57 PM CDTFreeze WatchPAH9 hr
Apr 14, 2:27 AM CDTFreeze WarningPAH30 hr
Apr 15, 1:32 PM CDTFreeze WarningPAH17 hr
Apr 17, 2:27 AM CDTFrost AdvisoryPAH30 hr
Apr 24, 3:00 AM CDTDense Fog AdvisoryPAH6 hr
Apr 28, 6:32 PM CDTMesoscale DiscussionSPC118 min
Apr 28, 6:41 PM CDTMesoscale DiscussionSPC64 min
Apr 28, 7:35 PM CDTSevere Thunderstorm WatchSPC7 hr
Apr 28, 9:55 PM CDTSpecial Weather StatementPAH50 min
May 5, 2:15 AM CDTLake Wind AdvisoryPAH17 hr
May 8, 3:59 AM CDTFrost AdvisoryPAH28 hr
May 8, 3:59 AM CDTLake Wind AdvisoryPAH16 hr
May 9, 3:13 PM CDTLake Wind AdvisoryPAH27 hr
May 14, 3:25 AM CDTLake Wind AdvisoryPAH16 hr
May 15, 5:04 AM CDTSpecial Weather StatementPAH71 min
May 15, 5:08 AM CDTSpecial Weather StatementPAH67 min
May 16, 3:38 PM CDTMesoscale DiscussionSPC3 hr
May 17, 1:44 PM CDTMesoscale DiscussionSPC2 hr
May 24, 8:23 PM CDTAreal Flood AdvisoryPAH7 hr
May 25, 4:29 PM CDTSevere Thunderstorm WarningPAH31 min
May 25, 7:34 PM CDTSpecial Weather StatementPAH41 min
May 25, 8:04 PM CDTSevere Thunderstorm WarningPAH11 min
Jun 9, 2:00 AM CDTWind AdvisoryPAH17 hr
Jun 10, 4:08 AM CDTLake Wind AdvisoryPAH15 hr
Jun 26, 2:27 AM CDTLake Wind AdvisoryPAH19 hr
Jun 27, 9:20 AM CDTLake Wind AdvisoryPAH11 hr
Jun 30, 3:26 AM CDTFlash Flood WatchPAH40 hr
Jun 30, 5:50 AM CDTFlash Flood WarningPAH4 hr
Jun 30, 2:59 PM CDTSpecial Weather StatementPAH46 min
Jun 30, 3:15 PM CDTFlash Flood WarningPAH3 hr
Jul 1, 1:17 PM CDTAreal Flood AdvisoryPAH3 hr
Jul 2, 5:05 AM CDTDense Fog AdvisoryPAH3 hr
Jul 15, 1:10 PM CDTMesoscale DiscussionSPC2 hr
Jul 15, 6:12 PM CDTTornado WatchSPC5 hr
Jul 15, 7:19 PM CDTSevere Thunderstorm WarningPAH41 min
Jul 15, 7:52 PM CDTFlash Flood WarningPAH6 hr
Jul 17, 3:10 AM CDTHeat AdvisoryPAH64 hr
Jul 20, 1:58 PM CDTFlash Flood WatchPAH5 hr
Jul 22, 11:54 AM CDTMesoscale DiscussionSPC2 hr
Jul 23, 1:41 PM CDTSpecial Weather StatementPAH34 min
Jul 23, 1:52 PM CDTAreal Flood AdvisoryPAH113 min
Jul 23, 2:11 PM CDTSpecial Weather StatementPAH34 min
Jul 27, 12:14 PM CDTMesoscale DiscussionSPC91 min
Jul 30, 1:52 AM CDTFlash Flood WatchPAH22 hr
Aug 9, 1:58 PM CDTHeat AdvisoryPAH29 hr
Aug 10, 2:38 PM CDTMesoscale DiscussionSPC2 hr
Aug 10, 5:17 PM CDTMesoscale DiscussionSPC118 min
Aug 10, 6:31 PM CDTSevere Thunderstorm WatchSPC5 hr
Aug 10, 6:49 PM CDTSevere Thunderstorm WarningPAH56 min
Aug 10, 7:29 PM CDTMesoscale DiscussionSPC91 min
Aug 12, 11:33 AM CDTFlash Flood WatchPAH7 hr
Aug 12, 12:06 PM CDTFlash Flood WarningPAH3 hr
Aug 13, 10:56 AM CDTFlash Flood WatchPAH9 hr
Aug 22, 3:25 AM CDTDense Fog AdvisoryPAH6 hr
Sep 12, 6:41 AM CDTDense Fog AdvisoryPAH2 hr
Sep 12, 5:58 PM CDTAreal Flood AdvisoryPAH3 hr
Sep 30, 9:47 AM CDTLake Wind AdvisoryPAH7 hr
Oct 4, 2:00 AM CDTFrost AdvisoryPAH30 hr
Oct 15, 2:58 AM CDTFrost AdvisoryPAH30 hr
Oct 15, 2:13 PM CDTFreeze WarningPAH19 hr
Oct 16, 3:25 PM CDTRed Flag WarningPAH28 hr
Oct 28, 2:25 AM CDTFlood WatchPAH32 hr
Oct 30, 1:47 PM CDTFreeze WatchPAH37 hr
Nov 1, 2:14 AM CSTFreeze WarningPAH30 hr
Nov 14, 3:16 AM CSTWind AdvisoryPAH39 hr
Nov 14, 1:25 PM CSTAreal Flood AdvisoryPAH3 hr
Nov 19, 3:07 AM CSTRed Flag WarningPAH15 hr
Dec 23, 3:34 AM CSTWind AdvisoryPAH20 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 archive20192021

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.