Alert archive / Iowa / Mahaska County

Weather alerts in Mahaska County, Iowa, 2011

145 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Mahaska County and its neighbors

Each county as a circle sized by its count in 2011. Tap one for its archive.

Alerts
145
Warnings
50
Watches
27
Advisories
23
Busiest month
June49 alerts
Busiest day
June 14, 201110 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 2 tornado warnings covering Mahaska County in 2011 had a tornado report inside them; 0 of 1 tornado reports fell inside a warning.

Mahaska County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings20100%10%
Severe thunderstorm warnings251348%1675%30 min
Flash flood warnings2150%0

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Des Moines, IA: tornado warnings581967%5375%27 min
NWS Des Moines, IA: severe thunderstorm warnings31317444%46874%22 min
NWS Des Moines, IA: flash flood warnings341362%3087%136 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 9, 3:20 PM CSTWinter Weather AdvisoryDMX51 hr
Jan 16, 3:38 PM CSTWinter Weather AdvisoryDMX26 hr
Jan 17, 2:50 AM CSTMesoscale DiscussionSPC4 hr
Jan 17, 6:35 AM CSTMesoscale DiscussionSPC4 hr
Jan 30, 4:01 AM CSTWinter Storm WatchDMX36 hr
Jan 30, 4:01 AM CSTWinter Weather AdvisoryDMX68 hr
Jan 31, 4:20 PM CSTBlizzard WarningDMX42 hr
Feb 1, 10:36 AM CSTMesoscale DiscussionSPC6 hr
Feb 1, 3:36 PM CSTMesoscale DiscussionSPC6 hr
Feb 2, 3:48 AM CSTWinter Weather AdvisoryDMX8 hr
Feb 2, 3:09 PM CSTWind Chill AdvisoryDMX18 hr
Feb 7, 3:35 AM CSTWind Chill AdvisoryDMX32 hr
Feb 8, 3:44 PM CSTWind Chill AdvisoryDMX20 hr
Feb 16, 12:59 AM CSTDense Fog AdvisoryDMX9 hr
Feb 16, 6:00 PM CSTDense Fog AdvisoryDMX16 hr
Feb 18, 12:05 AM CSTRiver Flood WarningDMX6 hr
Feb 20, 10:30 AM CSTRiver Flood WarningDMX24 hr
Feb 24, 3:47 AM CSTWinter Weather AdvisoryDMX20 hr
Feb 24, 12:05 PM CSTWinter Storm WarningDMX12 hr
Feb 27, 3:42 PM CSTWinter Weather AdvisoryDMX7 hr
Feb 27, 5:50 PM CSTMesoscale DiscussionSPC6 hr
Mar 20, 2:51 PM CDTMesoscale DiscussionSPC114 min
Mar 21, 12:22 PM CDTSevere Thunderstorm WarningDMX38 min
Mar 21, 1:00 PM CDTSevere Thunderstorm WarningDMX45 min
Mar 22, 2:03 PM CDTTornado WatchSPC7 hr
Mar 22, 8:00 PM CDTMesoscale DiscussionSPC60 min
Mar 22, 8:35 PM CDTTornado WatchSPC5 hr
Mar 22, 8:42 PM CDTSevere Thunderstorm WarningDMX33 min
Mar 22, 8:49 PM CDTSevere Thunderstorm WarningDMX41 min
Mar 22, 9:07 PM CDTSevere Thunderstorm WarningDMX23 min
Mar 22, 9:15 PM CDTTornado WarningDMX30 min
Mar 22, 9:32 PM CDTSevere Thunderstorm WarningDMX43 min
Apr 3, 3:47 PM CDTWind AdvisoryDMX26 hr
Apr 3, 4:49 PM CDTMesoscale DiscussionSPC56 min
Apr 3, 5:57 PM CDTTornado WatchSPC6 hr
Apr 3, 6:00 PM CDTSevere Thunderstorm WarningDMX45 min
Apr 3, 6:36 PM CDTSevere Thunderstorm WarningDMX24 min
Apr 3, 7:44 PM CDTMesoscale DiscussionSPC61 min
Apr 10, 3:54 AM CDTWind AdvisoryDMX15 hr
Apr 15, 6:59 AM CDTWind AdvisoryDMX9 hr
May 2, 3:48 PM CDTFrost AdvisoryDMX15 hr
May 3, 4:05 PM CDTFreeze WarningDMX15 hr
May 11, 8:09 AM CDTMesoscale DiscussionSPC66 min
May 11, 2:53 PM CDTTornado WatchSPC6 hr
May 11, 3:38 PM CDTMesoscale DiscussionSPC2 hr
May 11, 6:17 PM CDTMesoscale DiscussionSPC28 min
May 12, 6:05 PM CDTSevere Thunderstorm WatchSPC7 hr
May 12, 10:27 PM CDTMesoscale DiscussionSPC63 min
May 21, 2:25 PM CDTSevere Thunderstorm WatchSPC10 hr
May 21, 8:55 PM CDTMesoscale DiscussionSPC65 min
May 21, 10:19 PM CDTSevere Thunderstorm WarningDMX26 min
May 22, 4:41 AM CDTMesoscale DiscussionSPC2 hr
May 22, 10:53 AM CDTMesoscale DiscussionSPC2 hr
May 22, 12:51 PM CDTTornado WatchSPC10 hr
May 22, 2:02 PM CDTSevere Thunderstorm WarningDMX43 min
May 25, 4:22 AM CDTWind AdvisoryDMX17 hr
May 25, 3:18 PM CDTRiver Flood WarningDMX18 hr
May 29, 8:17 AM CDTSevere Thunderstorm WarningDMX43 min
May 29, 8:39 AM CDTMesoscale DiscussionSPC66 min
May 29, 5:06 PM CDTRiver Flood WarningDMX11 hr
Jun 5, 2:52 AM CDTMesoscale DiscussionSPC2 hr
Jun 5, 3:59 AM CDTSevere Thunderstorm WarningDMX46 min
Jun 5, 4:38 AM CDTSevere Thunderstorm WarningDMX52 min
Jun 5, 5:00 AM CDTSevere Thunderstorm WatchSPC7 hr
Jun 8, 3:36 PM CDTMesoscale DiscussionSPC84 min
Jun 8, 5:18 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 8, 8:43 PM CDTMesoscale DiscussionSPC92 min
Jun 9, 1:44 AM CDTMesoscale DiscussionSPC2 hr
Jun 9, 9:50 AM CDTMesoscale DiscussionSPC55 min
Jun 9, 2:01 PM CDTRiver Flood WarningDMX65 hr
Jun 9, 2:01 PM CDTRiver Flood WarningDMX63 hr
Jun 9, 3:44 PM CDTFlash Flood WatchDMX12 hr
Jun 9, 9:48 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 9, 10:49 PM CDTSevere Thunderstorm WarningDMX41 min
Jun 9, 11:45 PM CDTMesoscale DiscussionSPC90 min
Jun 10, 1:39 AM CDTMesoscale DiscussionSPC2 hr
Jun 10, 2:21 AM CDTFlash Flood WarningDMX6 hr
Jun 10, 8:29 AM CDTAreal Flood WarningDMX24 hr
Jun 13, 3:32 PM CDTFlash Flood WatchDMX36 hr
Jun 13, 9:23 PM CDTMesoscale DiscussionSPC97 min
Jun 13, 11:57 PM CDTMesoscale DiscussionSPC93 min
Jun 14, 1:01 AM CDTSevere Thunderstorm WarningDMX16 min
Jun 14, 1:16 AM CDTSevere Thunderstorm WarningDMX44 min
Jun 14, 2:59 AM CDTRiver Flood WarningDMX53 hr
Jun 14, 3:21 AM CDTMesoscale DiscussionSPC3 hr
Jun 14, 3:54 AM CDTSevere Thunderstorm WarningDMX51 min
Jun 14, 5:05 AM CDTFlash Flood WarningDMX6 hr
Jun 14, 6:32 AM CDTRiver Flood WarningDMX34 hr
Jun 14, 10:57 AM CDTAreal Flood WarningDMX24 hr
Jun 15, 11:02 AM CDTAreal Flood WarningDMX10 hr
Jun 19, 6:51 PM CDTTornado WatchSPC7 hr
Jun 19, 9:16 PM CDTMesoscale DiscussionSPC59 min
Jun 19, 11:14 PM CDTFlash Flood WatchDMX11 hr
Jun 20, 1:13 AM CDTSevere Thunderstorm WarningDMX47 min
Jun 20, 1:40 AM CDTMesoscale DiscussionSPC35 min
Jun 20, 3:46 AM CDTSevere Thunderstorm WatchSPC5 hr
Jun 20, 7:29 AM CDTMesoscale DiscussionSPC61 min
Jun 20, 1:42 PM CDTRiver Flood WarningDMX14 hr
Jun 20, 3:14 PM CDTFlash Flood WatchDMX12 hr
Jun 20, 8:32 PM CDTRiver Flood WarningDMX7 hr
Jun 20, 10:22 PM CDTMesoscale DiscussionSPC83 min
Jun 20, 10:58 PM CDTTornado WatchSPC4 hr
Jun 26, 3:42 PM CDTFlash Flood WatchDMX14 hr
Jun 26, 4:56 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 26, 8:48 PM CDTMesoscale DiscussionSPC117 min
Jun 26, 9:03 PM CDTRiver Flood WarningDMX4 days
Jun 26, 9:03 PM CDTRiver Flood WarningDMX37 hr
Jun 26, 10:08 PM CDTSevere Thunderstorm WarningDMX67 min
Jun 29, 3:38 PM CDTHeat AdvisoryDMX51 hr
Jul 5, 6:10 PM CDTTornado WatchSPC4 hr
Jul 5, 7:49 PM CDTMesoscale DiscussionSPC56 min
Jul 10, 2:06 PM CDTHeat AdvisoryDMX29 hr
Jul 11, 1:08 AM CDTSevere Thunderstorm WatchSPC13 min
Jul 11, 1:21 AM CDTSevere Thunderstorm WatchSPC4 hr
Jul 11, 2:36 AM CDTMesoscale DiscussionSPC114 min
Jul 14, 3:37 PM CDTExcessive Heat WatchDMX24 hr
Jul 15, 8:26 AM CDTRiver Flood WarningDMX55 hr
Jul 15, 3:32 PM CDTExcessive Heat WarningDMX6 days
Jul 21, 10:22 AM CDTRiver Flood WarningDMX8 days
Jul 21, 3:45 PM CDTMesoscale DiscussionSPC90 min
Jul 21, 7:09 PM CDTMesoscale DiscussionSPC96 min
Jul 22, 3:40 AM CDTExcessive Heat WarningDMX41 hr
Jul 22, 3:00 PM CDTMesoscale DiscussionSPC90 min
Jul 22, 8:02 PM CDTSevere Thunderstorm WarningDMX43 min
Jul 22, 8:47 PM CDTSevere Thunderstorm WarningDMX43 min
Jul 22, 10:17 PM CDTSevere Thunderstorm WarningDMX43 min
Jul 23, 4:57 PM CDTMesoscale DiscussionSPC93 min
Jul 23, 5:16 PM CDTSevere Thunderstorm WatchSPC4 hr
Jul 26, 11:30 AM CDTHeat AdvisoryDMX35 hr
Jul 28, 10:56 AM CDTHeat AdvisoryDMX11 hr
Jul 28, 5:40 PM CDTMesoscale DiscussionSPC95 min
Jul 30, 3:47 PM CDTHeat AdvisoryDMX72 hr
Aug 2, 3:53 AM CDTExcessive Heat WarningDMX15 hr
Aug 2, 12:57 PM CDTMesoscale DiscussionSPC93 min
Aug 6, 8:10 PM CDTMesoscale DiscussionSPC2 hr
Aug 6, 10:14 PM CDTSevere Thunderstorm WatchSPC5 hr
Aug 6, 11:06 PM CDTMesoscale DiscussionSPC114 min
Aug 6, 11:48 PM CDTSevere Thunderstorm WarningDMX57 min
Aug 23, 12:45 AM CDTMesoscale DiscussionSPC2 hr
Sep 2, 2:41 PM CDTMesoscale DiscussionSPC94 min
Sep 2, 10:23 PM CDTSevere Thunderstorm WatchSPC6 hr
Sep 2, 11:56 PM CDTMesoscale DiscussionSPC94 min
Sep 28, 3:50 PM CDTWind AdvisoryDMX27 hr
Oct 20, 3:42 AM CDTFreeze WarningDMX29 hr
Nov 8, 3:42 AM CSTWinter Weather AdvisoryDMX29 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 archive20102012

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.