Alert archive / Iowa / Des Moines County

Weather alerts in Des Moines County, Iowa, 2011

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

Des Moines County and its neighbors

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

Alerts: 146
Warnings: 48
Watches: 21
Advisories: 28
Busiest month: June41 alerts
Busiest day: May 25, 201111 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 2 tornado warnings covering Des Moines County in 2011 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 17 minutes after it went out.

Des Moines County, 2011

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	2	1	50%	1	100%	17 min
Severe thunderstorm warnings	13	9	31%	7	29%	4 min
Flash flood warnings	5	5	0%	3	100%	15 min

Each office's whole area, 2011

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Quad Cities, IA: tornado warnings	15	7	53%	14	71%	15 min
NWS Quad Cities, IA: severe thunderstorm warnings	157	110	30%	411	81%	27 min
NWS Quad Cities, IA: flash flood warnings	30	23	23%	69	77%	164 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.

Issued	Product	Office	Lasted
Jan 10, 4:17 AM CST	Winter Weather Advisory	DVN	38 hr
Jan 16, 3:50 PM CST	Winter Weather Advisory	DVN	28 hr
Jan 17, 6:35 AM CST	Mesoscale Discussion	SPC	4 hr
Jan 30, 3:40 AM CST	Winter Storm Watch	DVN	37 hr
Jan 31, 4:12 PM CST	Blizzard Warning	DVN	44 hr
Feb 1, 10:36 AM CST	Mesoscale Discussion	SPC	6 hr
Feb 1, 3:36 PM CST	Mesoscale Discussion	SPC	6 hr
Feb 2, 3:38 PM CST	Wind Chill Advisory	DVN	19 hr
Feb 7, 3:31 PM CST	Wind Chill Advisory	DVN	20 hr
Feb 16, 5:00 AM CST	Dense Fog Advisory	DVN	8 hr
Feb 18, 9:54 AM CST	River Flood Warning	DVN	36 hr
Feb 20, 9:42 AM CST	River Flood Warning	DVN	56 hr
Feb 24, 3:20 AM CST	Winter Storm Warning	DVN	17 hr
Feb 24, 3:20 AM CST	Winter Weather Advisory	DVN	26 hr
Feb 24, 5:20 PM CST	Mesoscale Discussion	SPC	6 hr
Feb 27, 3:37 PM CST	Winter Weather Advisory	DVN	11 hr
Feb 27, 5:50 PM CST	Mesoscale Discussion	SPC	6 hr
Mar 11, 3:29 AM CST	Dense Fog Advisory	DVN	7 hr
Mar 20, 9:31 PM CDT	Special Weather Statement	DVN	44 min
Mar 22, 8:00 PM CDT	Mesoscale Discussion	SPC	60 min
Mar 22, 11:21 PM CDT	Mesoscale Discussion	SPC	84 min
Mar 22, 11:24 PM CDT	Severe Thunderstorm Warning	DVN	66 min
Mar 23, 2:47 PM CDT	River Flood Warning	DVN	51 days
Mar 23, 2:47 PM CDT	River Flood Warning	DVN	52 days
Mar 23, 2:47 PM CDT	River Flood Warning	DVN	57 days
Mar 23, 2:47 PM CDT	River Flood Warning	DVN	57 days
Apr 3, 4:49 PM CDT	Mesoscale Discussion	SPC	56 min
Apr 3, 5:57 PM CDT	Tornado Watch	SPC	6 hr
Apr 3, 7:44 PM CDT	Mesoscale Discussion	SPC	61 min
Apr 3, 8:28 PM CDT	Severe Thunderstorm Warning	DVN	46 min
Apr 3, 9:36 PM CDT	Severe Thunderstorm Warning	DVN	38 min
Apr 4, 11:58 AM CDT	Wind Advisory	DVN	6 hr
Apr 10, 3:55 AM CDT	Wind Advisory	DVN	12 hr
Apr 10, 5:03 PM CDT	Mesoscale Discussion	SPC	57 min
Apr 10, 6:05 PM CDT	Tornado Watch	SPC	7 hr
Apr 15, 4:30 AM CDT	Wind Advisory	DVN	15 hr
Apr 19, 5:21 AM CDT	Special Weather Statement	DVN	114 min
May 2, 3:33 PM CDT	Frost Advisory	DVN	15 hr
May 3, 3:15 PM CDT	Freeze Warning	DVN	16 hr
May 11, 1:23 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
May 11, 3:38 PM CDT	Mesoscale Discussion	SPC	2 hr
May 22, 4:41 AM CDT	Mesoscale Discussion	SPC	2 hr
May 22, 10:53 AM CDT	Mesoscale Discussion	SPC	2 hr
May 22, 12:51 PM CDT	Tornado Watch	SPC	10 hr
May 22, 5:47 PM CDT	Mesoscale Discussion	SPC	88 min
May 25, 2:38 AM CDT	Flash Flood Watch	DVN	20 hr
May 25, 3:46 AM CDT	Special Weather Statement	DVN	59 min
May 25, 9:27 AM CDT	River Flood Warning	DVN	6 days
May 25, 11:46 AM CDT	River Flood Warning	DVN	13 days
May 25, 11:46 AM CDT	River Flood Warning	DVN	14 days
May 25, 2:31 PM CDT	Tornado Watch	SPC	7 hr
May 25, 4:35 PM CDT	Tornado Warning	DVN	40 min
May 25, 4:55 PM CDT	Flash Flood Warning	DVN	5 hr
May 25, 5:05 PM CDT	Severe Thunderstorm Warning	DVN	40 min
May 25, 5:11 PM CDT	Tornado Warning	DVN	23 min
May 25, 5:34 PM CDT	Flash Flood Warning	DVN	4 hr
May 27, 7:24 PM CDT	River Flood Warning	DVN	16 hr
May 29, 5:05 AM CDT	Dense Fog Advisory	DVN	4 hr
May 29, 8:39 AM CDT	Mesoscale Discussion	SPC	66 min
May 29, 8:53 AM CDT	Severe Thunderstorm Watch	SPC	6 hr
May 29, 9:18 AM CDT	Severe Thunderstorm Warning	DVN	57 min
May 29, 9:58 AM CDT	Severe Thunderstorm Warning	DVN	62 min
May 29, 10:15 AM CDT	Severe Thunderstorm Warning	DVN	60 min
May 29, 10:00 PM CDT	River Flood Warning	DVN	6 days
May 30, 11:14 AM CDT	River Flood Warning	DVN	47 hr
Jun 2, 3:45 PM CDT	River Flood Warning	DVN	52 hr
Jun 2, 5:29 PM CDT	Areal Flood Advisory	DVN	3 hr
Jun 4, 4:47 PM CDT	Mesoscale Discussion	SPC	28 min
Jun 4, 4:53 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 5, 2:25 AM CDT	Special Weather Statement	DVN	50 min
Jun 5, 2:52 AM CDT	Mesoscale Discussion	SPC	2 hr
Jun 5, 5:00 AM CDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 5, 6:13 AM CDT	Flash Flood Warning	DVN	6 hr
Jun 5, 9:02 AM CDT	Special Weather Statement	DVN	43 min
Jun 5, 9:16 AM CDT	Special Weather Statement	DVN	59 min
Jun 6, 3:28 AM CDT	Heat Advisory	DVN	64 hr
Jun 8, 3:36 PM CDT	Mesoscale Discussion	SPC	84 min
Jun 8, 8:43 PM CDT	Mesoscale Discussion	SPC	92 min
Jun 9, 1:44 AM CDT	Mesoscale Discussion	SPC	2 hr
Jun 9, 3:12 AM CDT	Flash Flood Watch	DVN	28 hr
Jun 10, 10:40 AM CDT	River Flood Warning	DVN	9 days
Jun 10, 10:40 AM CDT	River Flood Warning	DVN	9 days
Jun 13, 1:46 PM CDT	Special Weather Statement	DVN	59 min
Jun 13, 3:47 PM CDT	Flash Flood Watch	DVN	39 hr
Jun 13, 8:37 PM CDT	River Flood Warning	DVN	9 days
Jun 13, 9:23 PM CDT	Mesoscale Discussion	SPC	97 min
Jun 13, 11:57 PM CDT	Mesoscale Discussion	SPC	93 min
Jun 14, 11:12 AM CDT	Special Weather Statement	DVN	63 min
Jun 15, 12:03 AM CDT	Flash Flood Warning	DVN	9 hr
Jun 15, 1:55 AM CDT	Mesoscale Discussion	SPC	3 hr
Jun 19, 10:17 PM CDT	Flash Flood Watch	DVN	15 hr
Jun 19, 11:42 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 20, 12:31 AM CDT	Special Weather Statement	DVN	44 min
Jun 20, 2:00 AM CDT	Severe Thunderstorm Warning	DVN	34 min
Jun 20, 2:45 AM CDT	Special Weather Statement	DVN	75 min
Jun 20, 4:08 AM CDT	Mesoscale Discussion	SPC	67 min
Jun 20, 3:25 PM CDT	Flash Flood Watch	DVN	12 hr
Jun 20, 9:45 PM CDT	River Flood Warning	DVN	13 hr
Jun 26, 4:46 PM CDT	Flash Flood Watch	DVN	14 hr
Jun 26, 6:22 PM CDT	Mesoscale Discussion	SPC	83 min
Jun 26, 8:31 PM CDT	Severe Thunderstorm Warning	DVN	59 min
Jun 26, 9:37 PM CDT	Flash Flood Warning	DVN	9 hr
Jun 26, 10:02 PM CDT	Severe Thunderstorm Watch	SPC	5 hr
Jun 26, 10:16 PM CDT	River Flood Warning	DVN	36 hr
Jun 29, 3:18 PM CDT	Excessive Heat Watch	DVN	13 hr
Jun 30, 3:55 AM CDT	Heat Advisory	DVN	44 hr
Jul 10, 1:58 PM CDT	Heat Advisory	DVN	5 hr
Jul 10, 2:45 PM CDT	Mesoscale Discussion	SPC	2 hr
Jul 11, 3:12 AM CDT	Heat Advisory	DVN	16 hr
Jul 12, 1:00 PM CDT	Mesoscale Discussion	SPC	2 hr
Jul 14, 3:40 PM CDT	Excessive Heat Watch	DVN	24 hr
Jul 15, 3:42 PM CDT	Excessive Heat Warning	DVN	9 days
Jul 21, 7:09 PM CDT	Mesoscale Discussion	SPC	96 min
Jul 23, 5:16 PM CDT	Severe Thunderstorm Watch	SPC	4 hr
Jul 23, 6:10 PM CDT	Special Weather Statement	DVN	50 min
Jul 23, 6:34 PM CDT	Severe Thunderstorm Warning	DVN	45 min
Jul 26, 10:53 AM CDT	Heat Advisory	DVN	10 hr
Jul 26, 4:27 PM CDT	Special Weather Statement	DVN	48 min
Jul 26, 4:39 PM CDT	Severe Thunderstorm Warning	DVN	40 min
Jul 27, 3:44 AM CDT	Heat Advisory	DVN	18 hr
Jul 28, 12:03 PM CDT	Heat Advisory	DVN	10 hr
Jul 28, 5:40 PM CDT	Mesoscale Discussion	SPC	95 min
Jul 30, 8:31 PM CDT	River Flood Warning	DVN	24 hr
Jul 30, 8:31 PM CDT	River Flood Warning	DVN	33 hr
Jul 30, 8:31 PM CDT	River Flood Warning	DVN	56 hr
Jul 31, 3:54 AM CDT	Heat Advisory	DVN	66 hr
Jul 31, 9:45 AM CDT	River Flood Warning	DVN	35 hr
Aug 2, 3:50 AM CDT	Excessive Heat Warning	DVN	18 hr
Aug 2, 12:57 PM CDT	Mesoscale Discussion	SPC	93 min
Aug 6, 10:14 PM CDT	Severe Thunderstorm Watch	SPC	5 hr
Aug 6, 11:06 PM CDT	Mesoscale Discussion	SPC	114 min
Aug 7, 1:14 AM CDT	Severe Thunderstorm Warning	DVN	61 min
Aug 8, 1:06 PM CDT	Mesoscale Discussion	SPC	84 min
Aug 17, 3:44 PM CDT	Mesoscale Discussion	SPC	91 min
Aug 24, 3:55 AM CDT	Heat Advisory	DVN	12 hr
Sep 1, 10:40 AM CDT	Heat Advisory	DVN	32 hr
Sep 3, 2:42 PM CDT	Special Weather Statement	DVN	48 min
Sep 3, 2:52 PM CDT	Severe Thunderstorm Warning	DVN	53 min
Sep 28, 3:57 PM CDT	Wind Advisory	DVN	27 hr
Oct 1, 2:47 PM CDT	Frost Advisory	DVN	17 hr
Oct 11, 3:43 PM CDT	Special Weather Statement	DVN	62 min
Oct 12, 3:51 PM CDT	Special Weather Statement	DVN	54 min
Oct 20, 3:20 AM CDT	Freeze Warning	DVN	30 hr
Oct 25, 6:56 PM CDT	Mesoscale Discussion	SPC	3 hr
Nov 23, 4:53 AM CST	Dense Fog Advisory	DVN	7 hr
Dec 6, 7:45 AM CST	Winter Weather Advisory	DVN	6 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

Product	Alerts
Severe storms
Severe Thunderstorm Warning	13
Tornado Warning	2
Severe Thunderstorm Watch	8
Tornado Watch	4
Mesoscale Discussion	34
Special Weather Statement	15
Flooding
Flash Flood Warning	5
River Flood Warning	22
Flash Flood Watch	6
Areal Flood Advisory	1
Winter
Blizzard Warning	1
Winter Storm Warning	1
Winter Storm Watch	1
Winter Weather Advisory	5
Heat
Excessive Heat Warning	2
Excessive Heat Watch	2
Heat Advisory	10
Cold
Freeze Warning	2
Frost Advisory	2
Wind Chill Advisory	2
Wind and dust
Wind Advisory	4
Fog and smoke
Dense Fog Advisory	4

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2010 2012

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.