Alert archive / Iowa / Montgomery County

Weather alerts in Montgomery County, Iowa, 2011

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

Montgomery County and its neighbors

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

Alerts
139
Warnings
30
Watches
32
Advisories
40
Busiest month
June41 alerts
Busiest day
June 20, 20118 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 Montgomery County in 2011 had a tornado report inside them.

Montgomery County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings10100%0
Severe thunderstorm warnings221818%1090%28 min
Flash flood warnings220%1100%15 min

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Omaha, NE: tornado warnings31584%978%18 min
NWS Omaha, NE: severe thunderstorm warnings36424433%49186%22 min
NWS Omaha, NE: flash flood warnings31971%1694%86 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 7, 4:47 AM CSTWind AdvisoryOAX11 hr
Jan 8, 2:26 PM CSTWinter Weather AdvisoryOAX69 hr
Jan 11, 3:46 PM CSTWind Chill AdvisoryOAX18 hr
Jan 21, 3:24 PM CSTWinter Storm WatchOAX13 hr
Jan 22, 4:26 AM CSTWinter Weather AdvisoryOAX29 hr
Jan 30, 4:00 AM CSTWinter Storm WatchOAX13 hr
Jan 30, 4:55 PM CSTWinter Storm WarningOAX58 hr
Feb 1, 4:05 AM CSTWind Chill AdvisoryOAX31 hr
Feb 2, 3:24 PM CSTWind Chill AdvisoryOAX17 hr
Feb 7, 3:24 PM CSTWind Chill AdvisoryOAX21 hr
Feb 8, 3:24 PM CSTWind Chill AdvisoryOAX17 hr
Feb 15, 11:56 PM CSTDense Fog AdvisoryOAX10 hr
Feb 16, 10:28 AM CSTDense Fog AdvisoryOAX92 min
Feb 16, 6:17 PM CSTDense Fog AdvisoryOAX11 hr
Feb 23, 3:22 PM CSTWinter Weather AdvisoryOAX32 hr
Mar 7, 3:47 PM CSTWinter Weather AdvisoryOAX30 hr
Mar 22, 1:19 PM CDTMesoscale DiscussionSPC116 min
Mar 22, 2:03 PM CDTTornado WatchSPC7 hr
Mar 22, 4:57 PM CDTSevere Thunderstorm WarningOAX33 min
Mar 22, 5:08 PM CDTTornado WarningOAX22 min
Mar 25, 3:12 AM CDTWinter Weather AdvisoryOAX4 hr
Apr 3, 11:08 AM CDTWind AdvisoryOAX28 hr
Apr 9, 5:48 PM CDTTornado WatchSPC7 hr
Apr 9, 9:06 PM CDTMesoscale DiscussionSPC54 min
Apr 10, 3:52 AM CDTWind AdvisoryOAX11 hr
Apr 13, 10:07 PM CDTWind AdvisoryOAX27 hr
Apr 28, 3:57 PM CDTWind AdvisoryOAX28 hr
May 2, 3:58 PM CDTFrost AdvisoryOAX16 hr
May 4, 11:47 AM CDTWind AdvisoryOAX6 hr
May 11, 1:41 PM CDTSevere Thunderstorm WarningOAX23 min
May 11, 2:31 PM CDTMesoscale DiscussionSPC59 min
May 11, 2:53 PM CDTTornado WatchSPC6 hr
May 11, 4:34 PM CDTFlash Flood WarningOAX67 min
May 11, 8:16 PM CDTMesoscale DiscussionSPC59 min
May 12, 6:05 PM CDTSevere Thunderstorm WatchSPC7 hr
May 12, 10:27 PM CDTMesoscale DiscussionSPC63 min
May 21, 12:51 PM CDTMesoscale DiscussionSPC114 min
May 21, 2:25 PM CDTSevere Thunderstorm WatchSPC10 hr
May 21, 5:25 PM CDTMesoscale DiscussionSPC65 min
May 21, 6:07 PM CDTMesoscale DiscussionSPC53 min
May 21, 6:48 PM CDTSevere Thunderstorm WarningOAX42 min
May 21, 7:07 PM CDTSevere Thunderstorm WarningOAX38 min
May 21, 8:55 PM CDTMesoscale DiscussionSPC65 min
May 24, 1:10 PM CDTFlash Flood WatchOAX16 hr
May 29, 3:28 PM CDTWind AdvisoryOAX34 hr
May 29, 7:16 PM CDTTornado WatchSPC4 hr
Jun 8, 6:31 PM CDTMesoscale DiscussionSPC59 min
Jun 9, 1:44 AM CDTMesoscale DiscussionSPC2 hr
Jun 9, 3:31 AM CDTSevere Thunderstorm WarningOAX44 min
Jun 9, 9:50 AM CDTMesoscale DiscussionSPC55 min
Jun 9, 9:48 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 9, 10:47 PM CDTSevere Thunderstorm WarningOAX43 min
Jun 9, 11:36 PM CDTSevere Thunderstorm WarningOAX39 min
Jun 9, 11:45 PM CDTMesoscale DiscussionSPC90 min
Jun 10, 1:28 AM CDTAreal Flood AdvisoryOAX3 hr
Jun 10, 1:39 AM CDTMesoscale DiscussionSPC2 hr
Jun 13, 9:23 PM CDTMesoscale DiscussionSPC97 min
Jun 14, 3:53 PM CDTTornado WatchSPC8 hr
Jun 14, 7:47 PM CDTMesoscale DiscussionSPC58 min
Jun 16, 11:03 PM CDTSevere Thunderstorm WatchSPC5 hr
Jun 17, 6:44 PM CDTMesoscale DiscussionSPC91 min
Jun 17, 7:09 PM CDTSevere Thunderstorm WatchSPC3 hr
Jun 19, 9:16 PM CDTMesoscale DiscussionSPC59 min
Jun 19, 9:49 PM CDTTornado WatchSPC6 hr
Jun 19, 11:31 PM CDTSevere Thunderstorm WarningOAX44 min
Jun 20, 3:27 AM CDTMesoscale DiscussionSPC33 min
Jun 20, 3:46 AM CDTSevere Thunderstorm WatchSPC5 hr
Jun 20, 3:08 PM CDTTornado WatchSPC7 hr
Jun 20, 3:31 PM CDTFlash Flood WatchOAX7 hr
Jun 20, 6:53 PM CDTTornado WatchSPC6 hr
Jun 20, 7:46 PM CDTMesoscale DiscussionSPC59 min
Jun 20, 8:43 PM CDTSevere Thunderstorm WarningOAX62 min
Jun 25, 4:08 AM CDTSevere Thunderstorm WarningOAX42 min
Jun 25, 4:18 AM CDTAreal Flood AdvisoryOAX5 hr
Jun 25, 5:04 AM CDTFlash Flood WarningOAX4 hr
Jun 26, 6:16 AM CDTMesoscale DiscussionSPC59 min
Jun 26, 3:09 PM CDTMesoscale DiscussionSPC2 hr
Jun 26, 3:31 PM CDTFlash Flood WatchOAX12 hr
Jun 26, 4:56 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 26, 5:11 PM CDTSevere Thunderstorm WarningOAX30 min
Jun 26, 8:41 PM CDTSevere Thunderstorm WarningOAX49 min
Jun 26, 8:48 PM CDTMesoscale DiscussionSPC117 min
Jun 26, 8:53 PM CDTSevere Thunderstorm WarningOAX52 min
Jun 26, 9:08 PM CDTAreal Flood AdvisoryOAX2 hr
Jun 26, 9:31 PM CDTSevere Thunderstorm WarningOAX44 min
Jun 26, 10:01 PM CDTAreal Flood AdvisoryOAX86 min
Jun 29, 3:05 PM CDTHeat AdvisoryOAX28 hr
Jul 5, 2:49 PM CDTMesoscale DiscussionSPC86 min
Jul 5, 4:47 PM CDTSevere Thunderstorm WatchSPC8 hr
Jul 9, 3:44 PM CDTHeat AdvisoryOAX52 hr
Jul 10, 10:57 PM CDTSevere Thunderstorm WatchSPC4 hr
Jul 14, 3:09 AM CDTExcessive Heat WatchOAX36 hr
Jul 14, 2:30 PM CDTExcessive Heat WarningOAX6 days
Jul 15, 2:21 PM CDTMesoscale DiscussionSPC114 min
Jul 21, 3:45 PM CDTMesoscale DiscussionSPC90 min
Jul 21, 10:44 PM CDTSevere Thunderstorm WatchSPC89 min
Jul 22, 4:29 AM CDTHeat AdvisoryOAX15 hr
Jul 22, 3:00 PM CDTMesoscale DiscussionSPC90 min
Jul 22, 3:31 PM CDTHeat AdvisoryOAX28 hr
Jul 23, 4:57 PM CDTMesoscale DiscussionSPC93 min
Jul 23, 5:16 PM CDTSevere Thunderstorm WatchSPC4 hr
Jul 24, 4:01 AM CDTAreal Flood AdvisoryOAX3 hr
Jul 26, 4:28 AM CDTHeat AdvisoryOAX39 hr
Jul 30, 3:26 PM CDTHeat AdvisoryOAX60 hr
Aug 2, 3:40 AM CDTExcessive Heat WarningOAX15 hr
Aug 6, 5:32 PM CDTSevere Thunderstorm WatchSPC9 hr
Aug 6, 8:10 PM CDTMesoscale DiscussionSPC2 hr
Aug 6, 8:47 PM CDTSevere Thunderstorm WarningOAX43 min
Aug 6, 9:13 PM CDTSevere Thunderstorm WarningOAX47 min
Aug 6, 10:11 PM CDTSevere Thunderstorm WarningOAX49 min
Aug 6, 11:06 PM CDTMesoscale DiscussionSPC114 min
Aug 7, 10:28 PM CDTMesoscale DiscussionSPC2 hr
Aug 7, 11:34 PM CDTSevere Thunderstorm WatchSPC4 hr
Aug 18, 1:27 PM CDTSevere Thunderstorm WatchSPC8 hr
Aug 18, 2:51 PM CDTMesoscale DiscussionSPC84 min
Aug 18, 5:25 PM CDTSevere Thunderstorm WarningOAX50 min
Aug 18, 5:58 PM CDTSevere Thunderstorm WarningOAX28 min
Aug 18, 6:15 PM CDTAreal Flood AdvisoryOAX6 hr
Aug 18, 6:16 PM CDTSevere Thunderstorm WarningOAX44 min
Aug 18, 6:18 PM CDTMesoscale DiscussionSPC27 min
Aug 18, 8:29 PM CDTMesoscale DiscussionSPC61 min
Aug 22, 1:42 AM CDTMesoscale DiscussionSPC3 hr
Aug 22, 4:10 AM CDTSevere Thunderstorm WarningOAX50 min
Aug 28, 8:00 AM CDTSevere Thunderstorm WatchSPC5 hr
Aug 28, 10:41 AM CDTMesoscale DiscussionSPC94 min
Sep 2, 2:41 PM CDTMesoscale DiscussionSPC94 min
Sep 18, 10:51 PM CDTDense Fog AdvisoryOAX10 hr
Sep 30, 7:45 PM CDTFrost AdvisoryOAX12 hr
Oct 3, 3:32 PM CDTFire Weather WatchOAX12 hr
Oct 4, 3:45 AM CDTFire Weather WatchOAX24 hr
Oct 4, 3:45 AM CDTRed Flag WarningOAX15 hr
Oct 5, 3:35 AM CDTRed Flag WarningOAX15 hr
Oct 7, 11:07 AM CDTWind AdvisoryOAX6 hr
Oct 11, 2:28 AM CDTDense Fog AdvisoryOAX6 hr
Oct 11, 8:37 AM CDTDense Fog AdvisoryOAX83 min
Oct 18, 4:04 AM CDTFreeze WatchOAX11 hr
Oct 18, 3:07 PM CDTFreeze WarningOAX18 hr
Nov 25, 3:34 PM CSTWind AdvisoryOAX26 hr
Dec 30, 3:54 PM CSTWind AdvisoryOAX35 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.