The severe wind outbreak of July 11, 2011

506 wind reportsIowa, Illinois, Ohio and 18 more states

506 damaging wind reports across 21 states between 1:00 AM and 12:45 AM the next day CDT, 64 of them 65 knots (75 mph) or stronger; the strongest measured gust was 81 mph in Marshall County, IA. 64 hail reports and 1 tornado the same day.

Watch the day unfold

Severe wind day · July 11, 2011

How the day unfolded

Every damaging wind report of the day at its logged time, with the day's hail reports and tornadoes, and the counties they reached.

About this replay

Central time—Historical replay — logged report times

Wind reports—of 506 that day

Strongest gust—measured, so far

Largest hail—so far

The day’s milestones

Wind reportsLarger and brighter with speed; filled when measured, a ring when estimated

Hail and tornadoesHail reports as diamonds; the day's tornado paths in green

Counties reportingLit at their first report, brighter with a 65-knot gust or 2-inch hail

Source: NOAA Storm Prediction Center severe weather database (wind, hail and tornado reports with their logged times and places). Each report is a damage or measurement report, not a separate storm; several can describe one gust front. Tornado paths are drawn at a typical forward speed of 35 mph. Times are Central Daylight Time.

The day in numbers

Wind reports: 506; 34th of 15,807 days with wind reports since 1955
75 mph or more: 64; 18 of 86 mph (75 knots) or more
Strongest measured gust: 81 mph; 70 knots, Marshall County, IA
Measured: 58; reports with an instrument reading; the rest are estimates from damage
Killed by wind: 2; 8 injured
Counties reporting: 211; in 21 states

Hour by hour

Damaging wind reports in each hour, Central Daylight Time.

The strongest winds

The 100 strongest reports with a speed. Measured gusts come from an instrument; estimated speeds are judged from damage.

Strongest wind reports, July 11, 2011

4:55 AM	Benton County IA	120 mph	104	Estimated	0
5:00 AM	Benton County IA	120 mph	104	Estimated	0
4:25 AM	Tama County IA	115 mph	100	Estimated	0
3:30 AM	Polk County IA	110 mph	96	Estimated	0
4:30 AM	Tama County IA	110 mph	96	Estimated	0
4:35 AM	Tama County IA	110 mph	96	Estimated	0
3:20 AM	Polk County IA	98 mph	85	Estimated	0
4:09 AM	Marshall County IA	98 mph	85	Estimated	0
4:25 AM	Tama County IA	90 mph	78	Estimated	0
3:20 AM	Polk County IA	86 mph	75	Estimated	0
3:30 AM	Boone County IA	86 mph	75	Estimated	0
4:00 AM	Marion County IA	86 mph	75	Estimated	0
4:05 AM	Marshall County IA	86 mph	75	Estimated	0
4:23 AM	Marshall County IA	86 mph	75	Estimated	0
4:25 AM	Tama County IA	86 mph	75	Estimated	0
4:35 AM	Tama County IA	86 mph	75	Estimated	0
4:40 AM	Tama County IA	86 mph	75	Estimated	0
7:17 AM	Boone County IL	86 mph	75	Estimated	0
4:20 AM	Marshall County IA	81 mph	70	Measured	0
3:30 AM	Polk County IA	81 mph	70	Estimated	0
3:45 AM	Story County IA	81 mph	70	Estimated	0
4:04 AM	Marshall County IA	81 mph	70	Estimated	0
4:41 AM	Tama County IA	81 mph	70	Estimated	0
5:05 AM	Benton County IA	81 mph	70	Estimated	0
5:10 AM	Benton County IA	81 mph	70	Estimated	0
5:11 AM	Linn County IA	81 mph	70	Estimated	0
5:15 AM	Benton County IA	81 mph	70	Estimated	0
5:21 AM	Benton County IA	81 mph	70	Estimated	0
7:15 AM	Winnebago County IL	81 mph	70	Estimated	0
7:40 AM	Walworth County WI	81 mph	70	Estimated	0
9:00 AM	Ottawa County MI	81 mph	70	Estimated	0
9:10 AM	Van Buren County MI	81 mph	70	Estimated	0
9:16 AM	Allegan County MI	81 mph	70	Estimated	0
9:33 AM	St. Joseph County IN	81 mph	70	Estimated	0
9:57 AM	Kent County MI	81 mph	70	Estimated	1
8:56 PM	Greene County OH	77 mph	67	Measured	0
4:49 AM	Benton County IA	75 mph	65	Measured	0
8:12 AM	Cook County IL	75 mph	65	Measured	0
4:13 AM	Marshall County IA	75 mph	65	Estimated	0
5:59 AM	Grant County WI	75 mph	65	Estimated	0
6:10 AM	Lafayette County WI	75 mph	65	Estimated	0
6:10 AM	Dubuque County IA	75 mph	65	Estimated	0
6:42 AM	Ogle County IL	75 mph	65	Estimated	0
6:45 AM	Lee County IL	75 mph	65	Estimated	0
6:45 AM	Green County WI	75 mph	65	Estimated	0
6:55 AM	Winnebago County IL	75 mph	65	Estimated	0
7:00 AM	Rock County WI	75 mph	65	Estimated	0
7:10 AM	Lee County IL	75 mph	65	Estimated	0
7:14 AM	Ogle County IL	75 mph	65	Estimated	0
7:20 AM	DeKalb County IL	75 mph	65	Estimated	0
7:35 AM	McHenry County IL	75 mph	65	Estimated	0
7:40 AM	McHenry County IL	75 mph	65	Estimated	0
8:07 AM	Cook County IL	75 mph	65	Estimated	0
8:10 AM	Cook County IL	75 mph	65	Estimated	0
8:14 AM	Cook County IL	75 mph	65	Estimated	0
8:17 AM	DuPage County IL	75 mph	65	Estimated	0
9:25 AM	St. Joseph County IN	75 mph	65	Estimated	0
9:38 AM	Kalamazoo County MI	75 mph	65	Estimated	0
9:50 AM	Barry County MI	75 mph	65	Estimated	0
10:05 AM	Calhoun County MI	75 mph	65	Estimated	0
10:29 AM	Steuben County IN	75 mph	65	Estimated	0
10:30 AM	Noble County IN	75 mph	65	Estimated	0
10:30 AM	Noble County IN	75 mph	65	Estimated	0
11:33 AM	Wayne County MI	75 mph	65	Estimated	0
6:10 AM	Dubuque County IA	74 mph	64	Measured	0
5:23 AM	Linn County IA	72 mph	63	Measured	0
6:00 AM	Clinton County IA	72 mph	63	Measured	0
7:54 AM	Lake County IL	72 mph	63	Measured	0
8:19 AM	Cook County IL	72 mph	63	Measured	0
11:06 AM	Paulding County OH	71 mph	62	Measured	0
11:25 AM	Washtenaw County MI	71 mph	62	Measured	0
5:00 AM	Benton County IA	70 mph	61	Measured	0
8:00 AM	Lake County IL	70 mph	61	Measured	0
2:00 AM	O'Brien County IA	70 mph	61	Estimated	0
3:25 AM	Story County IA	70 mph	61	Estimated	0
3:25 AM	Polk County IA	70 mph	61	Estimated	0
4:00 AM	Jasper County IA	70 mph	61	Estimated	0
4:12 AM	Poweshiek County IA	70 mph	61	Estimated	0
4:22 AM	Tama County IA	70 mph	61	Estimated	0
4:30 AM	Benton County IA	70 mph	61	Estimated	0
4:45 AM	Benton County IA	70 mph	61	Estimated	0
5:01 AM	Benton County IA	70 mph	61	Estimated	0
5:03 AM	Benton County IA	70 mph	61	Estimated	0
5:10 AM	Linn County IA	70 mph	61	Estimated	0
5:10 AM	Buchanan County IA	70 mph	61	Estimated	0
5:10 AM	Buchanan County IA	70 mph	61	Estimated	0
5:12 AM	Linn County IA	70 mph	61	Estimated	0
5:14 AM	Benton County IA	70 mph	61	Estimated	0
5:15 AM	Linn County IA	70 mph	61	Estimated	0
5:16 AM	Benton County IA	70 mph	61	Estimated	0
5:20 AM	Linn County IA	70 mph	61	Estimated	0
5:20 AM	Linn County IA	70 mph	61	Estimated	0
5:20 AM	Jones County IA	70 mph	61	Estimated	0
5:24 AM	Linn County IA	70 mph	61	Estimated	0
5:24 AM	Linn County IA	70 mph	61	Estimated	0
5:25 AM	Linn County IA	70 mph	61	Estimated	0
5:25 AM	Linn County IA	70 mph	61	Estimated	0
5:27 AM	Clayton County IA	70 mph	61	Estimated	0
5:30 AM	Linn County IA	70 mph	61	Estimated	0
5:40 AM	Dubuque County IA	70 mph	61	Estimated	0

By state

Severe weather reports by state, July 11, 2011

Iowa	102	81 mph	0	—
Illinois	98	75 mph	0	—
Ohio	74	77 mph	31	1.75
Indiana	43	68 mph	3	1.75
Michigan	42	71 mph	2	0.75
Wisconsin	26	64 mph	0	—
Maryland	24	—	0	—
Virginia	21	—	0	—
Kentucky	18	61 mph	0	—
West Virginia	16	48 mph	2	1.00
Pennsylvania	9	—	0	—
Nebraska	8	68 mph	11	2.50
Wyoming	8	60 mph	3	1.75
Texas	5	67 mph	4	1.75
Mississippi	4	—	0	—
Maine	2	—	5	1.00
South Dakota	2	—	0	—
Arizona	1	60 mph	0	—
Idaho	1	58 mph	0	—
Minnesota	1	—	0	—
North Carolina	1	—	0	—
Colorado	0	—	3	1.75

Counties with the most wind reports

Cook CountyIL · 30 reports
Benton CountyIA · 17 reports
Linn CountyIA · 15 reports
Lake CountyIL · 14 reports
St. Joseph CountyIN · 11 reports
Polk CountyIA · 10 reports
Tama CountyIA · 9 reports
Wayne CountyMI · 9 reports
Frederick CountyMD · 8 reports
DuPage CountyIL · 8 reports

Hail and tornadoes that day

64 hail reports, 1 of 2 inches or more; 1 tornado.

Largest hail, July 11, 2011

6:30 PM	Sheridan County NE	2.50
2:00 PM	Clark County OH	1.75
2:30 PM	Madison County OH	1.75
5:00 PM	Niobrara County WY	1.75
5:38 PM	Sheridan County NE	1.75
6:17 PM	Sheridan County NE	1.75
7:32 PM	Logan County CO	1.75
7:34 PM	Clinton County IN	1.75
7:47 PM	Sheridan County NE	1.75
10:35 PM	Hall County TX	1.75
4:00 PM	Highland County OH	1.50
6:50 PM	Miami County OH	1.50
2:48 PM	Fayette County OH	1.25
3:29 PM	Clinton County OH	1.25
2:09 PM	Muskingum County OH	1.00
2:54 PM	Washington County OH	1.00
3:08 PM	Washington County OH	1.00
3:55 PM	Aroostook County ME	1.00
3:55 PM	Highland County OH	1.00
4:02 PM	Aroostook County ME	1.00
4:05 PM	Aroostook County ME	1.00
4:36 PM	Sheridan County NE	1.00
4:44 PM	Dawes County NE	1.00
5:00 PM	Niobrara County WY	1.00
5:20 PM	Sheridan County NE	1.00
5:25 PM	Sheridan County NE	1.00
5:43 PM	Jefferson County WV	1.00
6:05 PM	Aroostook County ME	1.00
6:10 PM	Aroostook County ME	1.00
6:55 PM	Miami County OH	1.00
7:05 PM	Sheridan County WY	1.00
7:17 PM	Randolph County IN	1.00
7:33 PM	Sheridan County NE	1.00
7:36 PM	Montgomery County OH	1.00
7:38 PM	Sheridan County NE	1.00
7:42 PM	Montgomery County OH	1.00
7:48 PM	Randolph County IN	1.00
8:00 PM	Randall County TX	1.00
8:09 PM	Darke County OH	1.00
8:35 PM	Cherry County NE	1.00
8:35 PM	Randall County TX	1.00
1:30 PM	Miami County OH	0.88
2:15 PM	Clark County OH	0.88
2:46 PM	Fayette County OH	0.88
5:21 PM	Scioto County OH	0.88
6:30 PM	Darke County OH	0.88
6:53 PM	Miami County OH	0.88
7:42 PM	Montgomery County OH	0.88
7:55 PM	Greene County OH	0.88
7:59 PM	Darke County OH	0.88

EF0 tornado2:52 AM CDT

2011 · On this date in other years · The biggest severe wind days

A report is a single damage or measurement report to the National Weather Service. Several reports can describe one gust front, so reports are not storms.
Reporting has grown with population, spotter networks and the internet, so counts from different decades are not directly comparable.
Thunderstorm wind reports start at 50 knots (58 mph). SPC began flagging measured against estimated speeds in 2006; earlier reports are shown as estimated.

Storm Prediction Center severe weather database, 1955 to 2025. A day is SPC’s calendar date in Central Standard Time; a severe wind day here has 300 or more damaging wind reports, or 15 or more of 75 knots (86 mph) or more.