Alert archive / Iowa / Cherokee County

Weather alerts in Cherokee County, Iowa, 2009

106 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Cherokee County and its neighbors

Each county as a circle sized by its count in 2009. Tap one for its archive.

Alerts
106
Warnings
22
Watches
20
Advisories
30
Busiest month
July22 alerts
Busiest day
August 3, 20098 alerts

Over time

By month

Warning verification

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

0 of 1 tornado warnings covering Cherokee County in 2009 had a tornado report inside them.

Cherokee County, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings10100%0
Severe thunderstorm warnings12742%250%19 min
Flash flood warnings330%0

Each office's whole area, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Sioux Falls, SD: tornado warnings491667%2378%21 min
NWS Sioux Falls, SD: severe thunderstorm warnings23217226%37481%19 min
NWS Sioux Falls, SD: flash flood warnings251828%3488%49 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 2, 3:55 PM CSTWinter Weather AdvisoryFSD29 hr
Jan 11, 4:33 AM CSTBlizzard WatchFSD24 hr
Jan 11, 2:50 PM CSTWinter Weather AdvisoryFSD30 hr
Jan 12, 10:56 AM CSTMesoscale DiscussionSPC6 hr
Jan 12, 6:27 PM CSTMesoscale DiscussionSPC4 hr
Jan 12, 6:40 PM CSTWind Chill AdvisoryFSD11 hr
Jan 13, 3:17 PM CSTWind Chill AdvisoryFSD33 hr
Jan 13, 6:12 PM CSTMesoscale DiscussionSPC4 hr
Jan 19, 6:41 PM CSTWinter Weather AdvisoryFSD7 hr
Jan 23, 3:33 AM CSTWind Chill AdvisoryFSD32 hr
Feb 9, 2:58 PM CSTWind AdvisoryFSD15 hr
Feb 11, 9:46 AM CSTRiver Flood WarningFSD67 hr
Feb 25, 11:07 AM CSTWinter Weather AdvisoryFSD29 hr
Feb 26, 6:33 AM CSTMesoscale DiscussionSPC5 hr
Mar 6, 3:39 PM CSTWinter Weather AdvisoryFSD44 hr
Mar 7, 8:09 PM CSTMesoscale DiscussionSPC4 hr
Mar 9, 3:44 AM CDTDense Fog AdvisoryFSD6 hr
Mar 9, 10:01 AM CDTDense Fog AdvisoryFSD119 min
Mar 9, 4:05 PM CDTWinter Weather AdvisoryFSD12 hr
Mar 9, 6:58 PM CDTDense Fog AdvisoryFSD5 hr
Mar 22, 3:44 AM CDTWind AdvisoryFSD44 hr
Mar 23, 6:04 PM CDTMesoscale DiscussionSPC116 min
Mar 23, 6:17 PM CDTSevere Thunderstorm WarningFSD43 min
Mar 30, 11:16 AM CDTWind AdvisoryFSD8 hr
Apr 2, 3:24 PM CDTWinter Storm WatchFSD30 hr
Apr 3, 10:40 AM CDTBlizzard WarningFSD41 hr
Apr 3, 4:05 PM CDTBlizzard WatchFSD6 hr
Apr 3, 9:45 PM CDTWinter Weather AdvisoryFSD39 hr
Apr 4, 9:11 PM CDTMesoscale DiscussionSPC4 hr
Apr 20, 10:33 AM CDTWind AdvisoryFSD8 hr
Apr 26, 9:34 AM CDTSevere Thunderstorm WatchSPC6 hr
Apr 26, 2:41 PM CDTMesoscale DiscussionSPC3 hr
May 6, 1:55 PM CDTMesoscale DiscussionSPC65 min
May 12, 3:34 AM CDTWind AdvisoryFSD17 hr
May 12, 3:49 PM CDTWind AdvisoryFSD30 hr
May 16, 3:51 AM CDTFrost AdvisoryFSD26 hr
May 19, 3:18 PM CDTWind AdvisoryFSD28 hr
Jun 7, 11:16 AM CDTMesoscale DiscussionSPC119 min
Jun 7, 5:21 PM CDTMesoscale DiscussionSPC54 min
Jun 17, 3:59 AM CDTDense Fog AdvisoryFSD5 hr
Jun 17, 5:43 PM CDTMesoscale DiscussionSPC92 min
Jun 17, 6:21 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 18, 4:20 AM CDTSevere Thunderstorm WatchSPC4 hr
Jun 18, 6:41 AM CDTMesoscale DiscussionSPC94 min
Jun 18, 6:49 AM CDTSevere Thunderstorm WarningFSD26 min
Jun 18, 7:16 AM CDTSevere Thunderstorm WarningFSD29 min
Jun 21, 12:33 PM CDTMesoscale DiscussionSPC87 min
Jun 21, 3:17 PM CDTTornado WatchSPC8 hr
Jun 21, 6:51 PM CDTMesoscale DiscussionSPC84 min
Jun 22, 3:41 PM CDTHeat AdvisoryFSD22 hr
Jun 23, 8:01 AM CDTSevere Thunderstorm WatchSPC6 hr
Jun 23, 11:31 AM CDTMesoscale DiscussionSPC89 min
Jun 24, 11:53 PM CDTSevere Thunderstorm WatchSPC5 hr
Jul 7, 1:47 PM CDTMesoscale DiscussionSPC58 min
Jul 7, 2:13 PM CDTSevere Thunderstorm WatchSPC8 hr
Jul 7, 6:12 PM CDTMesoscale DiscussionSPC63 min
Jul 7, 6:33 PM CDTMesoscale DiscussionSPC27 min
Jul 7, 8:39 PM CDTFlash Flood WarningFSD3 hr
Jul 7, 9:10 PM CDTFlash Flood WarningFSD3 hr
Jul 7, 9:22 PM CDTMesoscale DiscussionSPC53 min
Jul 7, 9:44 PM CDTSevere Thunderstorm WatchSPC5 hr
Jul 9, 3:41 AM CDTSevere Thunderstorm WatchSPC6 hr
Jul 9, 5:56 AM CDTMesoscale DiscussionSPC94 min
Jul 9, 12:07 PM CDTFlash Flood WatchFSD21 hr
Jul 9, 2:57 PM CDTMesoscale DiscussionSPC93 min
Jul 9, 7:02 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 9, 11:31 PM CDTMesoscale DiscussionSPC89 min
Jul 10, 6:36 AM CDTSevere Thunderstorm WarningFSD25 min
Jul 14, 1:42 PM CDTMesoscale DiscussionSPC93 min
Jul 14, 2:40 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 14, 8:00 PM CDTSevere Thunderstorm WarningFSD45 min
Jul 14, 8:27 PM CDTSevere Thunderstorm WarningFSD33 min
Jul 21, 12:20 PM CDTMesoscale DiscussionSPC55 min
Jul 29, 3:34 PM CDTTornado WarningFSD26 min
Jul 29, 4:12 PM CDTSevere Thunderstorm WarningFSD24 min
Jul 31, 7:43 PM CDTMesoscale DiscussionSPC2 hr
Aug 2, 8:41 PM CDTSevere Thunderstorm WatchSPC6 hr
Aug 2, 11:21 PM CDTMesoscale DiscussionSPC84 min
Aug 2, 11:26 PM CDTSevere Thunderstorm WarningFSD34 min
Aug 2, 11:32 PM CDTSevere Thunderstorm WarningFSD28 min
Aug 2, 11:49 PM CDTSevere Thunderstorm WarningFSD56 min
Aug 3, 1:03 AM CDTSevere Thunderstorm WarningFSD42 min
Aug 3, 1:44 AM CDTSevere Thunderstorm WarningFSD46 min
Aug 3, 2:07 AM CDTFlash Flood WarningFSD3 hr
Aug 7, 3:55 PM CDTMesoscale DiscussionSPC95 min
Aug 7, 8:58 PM CDTMesoscale DiscussionSPC92 min
Aug 9, 6:54 AM CDTSevere Thunderstorm WatchSPC7 hr
Aug 9, 9:55 AM CDTMesoscale DiscussionSPC35 min
Aug 12, 4:03 PM CDTMesoscale DiscussionSPC87 min
Aug 19, 5:19 PM CDTMesoscale DiscussionSPC26 min
Aug 19, 5:32 PM CDTSevere Thunderstorm WatchSPC6 hr
Sep 26, 2:26 PM CDTWind AdvisoryFSD30 hr
Sep 28, 3:20 PM CDTFrost AdvisoryFSD18 hr
Oct 9, 3:46 AM CDTFreeze WarningFSD29 hr
Dec 6, 3:33 PM CSTWinter Storm WatchFSD23 hr
Dec 7, 2:59 PM CSTWinter Storm WarningFSD23 hr
Dec 8, 1:33 PM CSTBlizzard WarningFSD25 hr
Dec 8, 9:38 PM CSTMesoscale DiscussionSPC6 hr
Dec 9, 4:10 AM CSTWind Chill AdvisoryFSD30 hr
Dec 13, 10:49 PM CSTWinter Weather AdvisoryFSD5 hr
Dec 21, 2:02 PM CSTWinter Storm WatchFSD24 hr
Dec 21, 4:39 PM CSTFreezing Rain AdvisoryFSD3 hr
Dec 22, 4:30 AM CSTWinter Storm WarningFSD4 days
Dec 23, 4:48 AM CSTWinter Weather AdvisoryFSD13 hr
Dec 23, 12:21 PM CSTMesoscale DiscussionSPC4 hr
Dec 26, 3:56 AM CSTWinter Weather AdvisoryFSD20 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 archive20082010

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.