Weather alerts in Louisa County, Iowa, 2018

203 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Louisa County and its neighbors

Each county as a circle sized by its count in 2018. Tap one for its archive.

Alerts: 203
Warnings: 57
Watches: 41
Advisories: 45
Busiest month: September41 alerts
Busiest day: June 21, 201811 alerts

Over time

By month

Warning verification

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

2 of 3 tornado warnings covering Louisa County in 2018 had a tornado report inside them.

Louisa County, 2018

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	3	2	33%	0
Severe thunderstorm warnings	9	8	11%	3	33%	6 min
Flash flood warnings	1	0	100%	0

Each office's whole area, 2018

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Quad Cities, IA: tornado warnings	47	14	70%	32	59%	8 min
NWS Quad Cities, IA: severe thunderstorm warnings	136	92	32%	249	75%	22 min
NWS Quad Cities, IA: flash flood warnings	29	19	34%	39	79%	73 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 2, 2:50 PM CST	Wind Chill Advisory	DVN	43 hr
Jan 2, 9:18 PM CST	Special Weather Statement	DVN	117 min
Jan 2, 11:20 PM CST	Special Weather Statement	DVN	115 min
Jan 3, 1:25 AM CST	Special Weather Statement	DVN	2 hr
Jan 6, 2:45 AM CST	Winter Weather Advisory	DVN	45 hr
Jan 6, 2:50 AM CST	Wind Chill Advisory	DVN	6 hr
Jan 7, 2:00 PM CST	Mesoscale Discussion	SPC	4 hr
Jan 8, 10:03 PM CST	Dense Fog Advisory	DVN	12 hr
Jan 11, 3:07 AM CST	Winter Weather Advisory	DVN	17 hr
Jan 11, 9:36 AM CST	Mesoscale Discussion	SPC	4 hr
Jan 11, 10:36 AM CST	Special Weather Statement	DVN	114 min
Jan 11, 12:00 PM CST	Special Weather Statement	DVN	2 hr
Jan 14, 2:45 PM CST	Wind Chill Advisory	DVN	44 hr
Jan 14, 2:45 PM CST	Winter Weather Advisory	DVN	21 hr
Jan 14, 4:36 PM CST	Special Weather Statement	DVN	84 min
Jan 14, 8:19 PM CST	Special Weather Statement	DVN	86 min
Feb 4, 1:53 PM CST	Winter Weather Advisory	DVN	32 hr
Feb 5, 11:36 AM CST	Mesoscale Discussion	SPC	6 hr
Feb 5, 4:57 PM CST	Mesoscale Discussion	SPC	4 hr
Feb 8, 2:59 AM CST	Winter Weather Advisory	DVN	39 hr
Feb 9, 9:43 AM CST	Special Weather Statement	DVN	2 hr
Feb 9, 3:09 PM CST	Winter Weather Advisory	DVN	18 hr
Feb 9, 6:26 PM CST	Winter Weather Advisory	DVN	3 hr
Feb 10, 3:14 PM CST	Winter Weather Advisory	DVN	18 hr
Feb 14, 5:42 PM CST	Dense Fog Advisory	DVN	20 hr
Feb 18, 2:28 AM CST	Dense Fog Advisory	DVN	8 hr
Feb 20, 9:37 AM CST	Flood Watch	DVN	6 hr
Feb 20, 3:19 PM CST	River Flood Warning	DVN	58 hr
Feb 20, 3:19 PM CST	River Flood Warning	DVN	4 days
Feb 21, 3:47 PM CST	Winter Weather Advisory	DVN	20 hr
Feb 22, 12:09 AM CST	River Flood Warning	DVN	43 hr
Feb 23, 3:13 PM CST	Winter Weather Advisory	DVN	20 hr
Mar 5, 1:48 AM CST	Special Weather Statement	DVN	87 min
Mar 5, 3:16 AM CST	Special Weather Statement	DVN	89 min
Mar 5, 4:16 AM CST	Special Weather Statement	DVN	89 min
Mar 5, 5:48 AM CST	Special Weather Statement	DVN	87 min
Mar 5, 7:15 AM CST	Special Weather Statement	DVN	90 min
Mar 6, 5:51 AM CST	Special Weather Statement	DVN	84 min
Mar 6, 6:51 AM CST	Special Weather Statement	DVN	114 min
Mar 16, 3:10 AM CDT	Winter Weather Advisory	DVN	32 hr
Mar 16, 7:35 PM CDT	Special Weather Statement	DVN	55 min
Mar 16, 8:29 PM CDT	Special Weather Statement	DVN	91 min
Mar 17, 11:14 AM CDT	Winter Weather Advisory	DVN	61 min
Mar 18, 2:25 AM CDT	Dense Fog Advisory	DVN	9 hr
Mar 23, 3:30 AM CDT	Winter Weather Advisory	DVN	40 hr
Mar 24, 6:53 PM CDT	Special Weather Statement	DVN	67 min
Mar 31, 6:13 AM CDT	Wind Advisory	DVN	10 hr
Apr 7, 3:08 PM CDT	Winter Weather Advisory	DVN	43 hr
Apr 9, 10:03 AM CDT	Winter Weather Advisory	DVN	94 min
Apr 19, 9:41 AM CDT	River Flood Watch	DVN	24 hr
Apr 27, 2:50 PM CDT	Red Flag Warning	DVN	5 hr
Apr 30, 11:08 AM CDT	River Flood Watch	DVN	35 hr
Apr 30, 11:08 AM CDT	River Flood Watch	DVN	35 hr
Apr 30, 11:08 AM CDT	River Flood Watch	DVN	35 hr
May 1, 10:01 PM CDT	River Flood Warning	DVN	19 days
May 1, 10:01 PM CDT	River Flood Warning	DVN	21 days
May 1, 10:01 PM CDT	River Flood Warning	DVN	21 days
May 2, 1:33 PM CDT	Mesoscale Discussion	SPC	117 min
May 2, 3:56 PM CDT	Severe Thunderstorm Watch	SPC	9 hr
May 2, 7:21 PM CDT	Mesoscale Discussion	SPC	84 min
May 2, 10:01 PM CDT	Mesoscale Discussion	SPC	89 min
May 3, 9:27 PM CDT	River Flood Watch	DVN	56 hr
May 4, 11:42 AM CDT	River Flood Watch	DVN	24 hr
May 4, 11:42 AM CDT	River Flood Watch	DVN	5 days
May 4, 11:42 AM CDT	River Flood Watch	DVN	5 days
May 6, 4:55 AM CDT	River Flood Warning	DVN	8 days
May 9, 4:05 AM CDT	River Flood Warning	DVN	3 days
May 9, 4:05 AM CDT	River Flood Warning	DVN	5 days
May 12, 3:50 AM CDT	Severe Thunderstorm Warning	DVN	40 min
May 12, 4:27 AM CDT	Special Weather Statement	DVN	63 min
May 14, 8:29 PM CDT	Severe Thunderstorm Warning	DVN	46 min
May 15, 10:14 PM CDT	River Flood Warning	DVN	22 hr
May 27, 3:47 PM CDT	Mesoscale Discussion	SPC	118 min
Jun 8, 12:51 PM CDT	Mesoscale Discussion	SPC	114 min
Jun 9, 6:30 PM CDT	Mesoscale Discussion	SPC	2 hr
Jun 9, 8:52 PM CDT	River Flood Watch	DVN	49 hr
Jun 10, 10:39 AM CDT	Special Weather Statement	DVN	51 min
Jun 11, 9:21 PM CDT	River Flood Warning	DVN	8 days
Jun 14, 11:53 AM CDT	Special Weather Statement	DVN	67 min
Jun 15, 3:25 AM CDT	Heat Advisory	DVN	4 days
Jun 15, 10:26 AM CDT	River Flood Watch	DVN	5 days
Jun 15, 10:26 AM CDT	River Flood Watch	DVN	6 days
Jun 16, 10:20 AM CDT	River Flood Warning	DVN	5 days
Jun 16, 10:20 AM CDT	River Flood Warning	DVN	5 days
Jun 20, 6:36 AM CDT	Special Weather Statement	DVN	24 min
Jun 20, 3:04 PM CDT	Tornado Watch	SPC	4 hr
Jun 20, 3:10 PM CDT	Severe Thunderstorm Warning	DVN	65 min
Jun 20, 5:13 PM CDT	Mesoscale Discussion	SPC	2 hr
Jun 20, 9:42 PM CDT	River Flood Watch	DVN	24 hr
Jun 20, 9:42 PM CDT	River Flood Watch	DVN	24 hr
Jun 20, 9:42 PM CDT	River Flood Watch	DVN	24 hr
Jun 21, 3:47 AM CDT	Flash Flood Watch	DVN	23 hr
Jun 21, 11:16 AM CDT	River Flood Warning	DVN	16 days
Jun 21, 11:16 AM CDT	River Flood Warning	DVN	18 days
Jun 21, 11:16 AM CDT	River Flood Warning	DVN	19 days
Jun 21, 11:16 AM CDT	Special Weather Statement	DVN	3 hr
Jun 21, 11:40 AM CDT	Special Weather Statement	DVN	20 min
Jun 21, 12:11 PM CDT	Special Weather Statement	DVN	49 min
Jun 21, 1:22 PM CDT	Special Weather Statement	DVN	53 min
Jun 21, 8:16 PM CDT	River Flood Watch	DVN	12 hr
Jun 22, 8:10 AM CDT	River Flood Warning	DVN	10 days
Jun 22, 9:43 AM CDT	River Flood Watch	DVN	10 hr
Jun 23, 6:40 PM CDT	Special Weather Statement	DVN	50 min
Jun 23, 7:46 PM CDT	Special Weather Statement	DVN	59 min
Jun 27, 3:11 PM CDT	Heat Advisory	DVN	24 hr
Jun 28, 3:31 PM CDT	Excessive Heat Warning	DVN	54 hr
Jun 28, 9:03 PM CDT	River Flood Watch	DVN	13 hr
Jun 29, 10:21 AM CDT	River Flood Warning	DVN	4 days
Jun 30, 7:15 PM CDT	Mesoscale Discussion	SPC	90 min
Jul 3, 3:48 PM CDT	Heat Advisory	DVN	28 hr
Jul 13, 3:37 AM CDT	Heat Advisory	DVN	15 hr
Jul 13, 3:57 PM CDT	Special Weather Statement	DVN	48 min
Jul 13, 4:07 PM CDT	Severe Thunderstorm Warning	DVN	32 min
Jul 19, 5:18 PM CDT	Mesoscale Discussion	SPC	57 min
Aug 5, 5:44 PM CDT	Mesoscale Discussion	SPC	2 hr
Aug 16, 3:00 AM CDT	Dense Fog Advisory	DVN	6 hr
Aug 25, 12:38 AM CDT	Special Weather Statement	DVN	37 min
Aug 25, 1:41 PM CDT	Heat Advisory	DVN	5 hr
Aug 26, 3:03 AM CDT	Heat Advisory	DVN	64 hr
Aug 28, 9:08 AM CDT	Flash Flood Watch	DVN	20 hr
Aug 28, 4:45 PM CDT	Mesoscale Discussion	SPC	60 min
Aug 28, 5:06 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Aug 28, 5:59 PM CDT	Severe Thunderstorm Warning	DVN	61 min
Aug 28, 6:18 PM CDT	Severe Thunderstorm Warning	DVN	42 min
Aug 28, 8:26 PM CDT	Severe Thunderstorm Warning	DVN	49 min
Aug 31, 7:12 PM CDT	Special Weather Statement	DVN	108 min
Sep 1, 3:44 AM CDT	Flash Flood Watch	DVN	24 hr
Sep 1, 10:01 AM CDT	River Flood Warning	DVN	15 days
Sep 1, 10:01 AM CDT	River Flood Warning	DVN	5 days
Sep 1, 10:01 AM CDT	River Flood Warning	DVN	14 days
Sep 1, 10:01 AM CDT	River Flood Warning	DVN	16 days
Sep 1, 10:01 AM CDT	River Flood Warning	DVN	16 days
Sep 1, 6:34 PM CDT	Mesoscale Discussion	SPC	56 min
Sep 1, 8:20 PM CDT	Severe Thunderstorm Watch	SPC	5 hr
Sep 1, 9:56 PM CDT	Special Weather Statement	DVN	49 min
Sep 1, 10:27 PM CDT	Mesoscale Discussion	SPC	63 min
Sep 2, 9:26 AM CDT	Flash Flood Watch	DVN	39 hr
Sep 2, 10:22 AM CDT	River Flood Warning	DVN	16 days
Sep 2, 10:22 AM CDT	River Flood Warning	DVN	16 days
Sep 3, 1:20 PM CDT	Mesoscale Discussion	SPC	2 hr
Sep 4, 3:56 AM CDT	Flash Flood Watch	DVN	39 hr
Sep 4, 11:21 AM CDT	River Flood Warning	DVN	12 days
Sep 5, 3:50 PM CDT	River Flood Warning	DVN	4 days
Sep 6, 2:38 PM CDT	Flash Flood Watch	DVN	36 hr
Sep 18, 10:41 AM CDT	Special Weather Statement	DVN	64 min
Sep 18, 11:47 AM CDT	Severe Thunderstorm Warning	DVN	58 min
Sep 18, 12:32 PM CDT	Severe Thunderstorm Warning	DVN	58 min
Sep 19, 10:38 AM CDT	River Flood Watch	DVN	35 hr
Sep 19, 11:51 AM CDT	Special Weather Statement	DVN	54 min
Sep 19, 9:52 PM CDT	River Flood Watch	DVN	37 hr
Sep 19, 9:52 PM CDT	River Flood Watch	DVN	24 hr
Sep 20, 10:31 AM CDT	River Flood Watch	DVN	24 hr
Sep 20, 9:17 PM CDT	River Flood Warning	DVN	33 days
Sep 20, 9:17 PM CDT	River Flood Warning	DVN	36 days
Sep 20, 9:17 PM CDT	River Flood Warning	DVN	38 days
Sep 21, 1:11 AM CDT	Special Weather Statement	DVN	79 min
Sep 21, 10:30 AM CDT	River Flood Warning	DVN	32 days
Sep 21, 11:17 AM CDT	River Flood Watch	DVN	24 hr
Sep 21, 9:58 PM CDT	River Flood Warning	DVN	40 days
Sep 25, 1:07 PM CDT	Mesoscale Discussion	SPC	113 min
Sep 25, 1:19 PM CDT	Tornado Warning	DVN	41 min
Sep 25, 1:36 PM CDT	Severe Thunderstorm Watch	SPC	8 hr
Sep 25, 1:49 PM CDT	Tornado Warning	DVN	41 min
Sep 25, 2:12 PM CDT	Tornado Warning	DVN	27 min
Sep 25, 3:39 PM CDT	Mesoscale Discussion	SPC	96 min
Sep 28, 11:11 AM CDT	River Flood Warning	DVN	33 days
Oct 1, 10:23 PM CDT	River Flood Warning	DVN	28 days
Oct 4, 9:29 AM CDT	River Flood Warning	DVN	12 days
Oct 4, 1:18 PM CDT	Flash Flood Watch	DVN	48 hr
Oct 5, 2:39 PM CDT	Mesoscale Discussion	SPC	3 hr
Oct 5, 6:03 PM CDT	Special Weather Statement	DVN	42 min
Oct 7, 2:44 PM CDT	Flash Flood Watch	DVN	70 hr
Oct 8, 3:18 PM CDT	Special Weather Statement	DVN	87 min
Oct 9, 3:42 AM CDT	Flash Flood Watch	DVN	33 hr
Oct 10, 6:51 AM CDT	Flash Flood Warning	DVN	2 hr
Oct 11, 3:40 AM CDT	Frost Advisory	DVN	28 hr
Oct 14, 3:21 PM CDT	Freeze Warning	DVN	18 hr
Oct 15, 3:14 AM CDT	Freeze Warning	DVN	30 hr
Oct 19, 7:36 PM CDT	Wind Advisory	DVN	20 hr
Oct 27, 2:31 PM CDT	Wind Advisory	DVN	26 hr
Nov 4, 10:48 AM CST	River Flood Watch	DVN	4 days
Nov 4, 10:48 AM CST	River Flood Watch	DVN	24 hr
Nov 4, 10:48 AM CST	River Flood Watch	DVN	24 hr
Nov 4, 7:21 PM CST	River Flood Warning	DVN	3 days
Nov 4, 7:21 PM CST	River Flood Warning	DVN	49 hr
Nov 4, 7:21 PM CST	River Flood Warning	DVN	63 hr
Nov 17, 7:47 PM CST	Winter Weather Advisory	DVN	7 hr
Nov 23, 3:29 AM CST	Winter Storm Watch	DVN	24 hr
Nov 24, 3:52 AM CST	Winter Storm Warning	DVN	44 hr
Nov 25, 11:54 AM CST	Mesoscale Discussion	SPC	6 hr
Nov 25, 12:09 PM CST	Blizzard Warning	DVN	18 hr
Nov 30, 3:37 AM CST	Dense Fog Advisory	DVN	6 hr
Dec 1, 7:28 AM CST	Wind Advisory	DVN	7 hr
Dec 1, 12:36 PM CST	Dense Fog Advisory	DVN	20 hr
Dec 1, 3:52 PM CST	Special Weather Statement	DVN	23 min
Dec 4, 7:19 AM CST	Winter Weather Advisory	DVN	3 hr
Dec 10, 12:42 AM CST	Dense Fog Advisory	DVN	9 hr
Dec 13, 9:42 AM CST	Dense Fog Advisory	DVN	3 hr
Dec 13, 4:56 PM CST	Dense Fog Advisory	DVN	3 hr
Dec 13, 11:58 PM CST	Dense Fog Advisory	DVN	9 hr
Dec 14, 3:57 PM CST	Dense Fog Advisory	DVN	11 hr
Dec 28, 2:50 AM CST	Winter Weather Advisory	DVN	9 hr
Dec 28, 2:37 PM CST	Winter Weather Advisory	DVN	7 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	9
Tornado Warning	3
Severe Thunderstorm Watch	4
Tornado Watch	1
Mesoscale Discussion	22
Special Weather Statement	38
Flooding
Flash Flood Warning	1
River Flood Warning	38
Flash Flood Watch	9
Flood Watch	1
River Flood Watch	25
Winter
Blizzard Warning	1
Winter Storm Warning	1
Winter Storm Watch	1
Winter Weather Advisory	19
Heat
Excessive Heat Warning	1
Heat Advisory	6
Cold
Freeze Warning	2
Frost Advisory	1
Wind Chill Advisory	3
Wind and dust
Wind Advisory	4
Fire
Red Flag Warning	1
Fog and smoke
Dense Fog Advisory	12

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2017 2019

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.