The severe wind outbreak of July 21, 2008

395 wind reportsIowa, Illinois, Indiana and 21 more states

395 damaging wind reports across 24 states between 1:00 AM and 12:45 AM the next day CDT, 54 of them 65 knots (75 mph) or stronger; the strongest measured gust was 94 mph in Rock Island County, IL. 129 hail reports and 4 tornadoes the same day.

Watch the day unfold

Severe wind day · July 21, 2008

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 395 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: 395; 87th of 15,807 days with wind reports since 1955
75 mph or more: 54; 10 of 86 mph (75 knots) or more
Strongest measured gust: 94 mph; 82 knots, Rock Island County, IL
Measured: 43; reports with an instrument reading; the rest are estimates from damage
Killed by wind: 2; 6 injured
Counties reporting: 186; in 24 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 21, 2008

2:52 AM	Dallas County IA	100 mph	87	Estimated	0
3:12 AM	Dallas County IA	100 mph	87	Estimated	0
3:13 AM	Dallas County IA	100 mph	87	Estimated	0
6:15 AM	Rock Island County IL	94 mph	82	Measured	0
2:45 AM	Guthrie County IA	92 mph	80	Estimated	0
6:00 PM	Rowan County NC	92 mph	80	Estimated	0
6:15 AM	Henry County IL	90 mph	78	Estimated	2
2:50 AM	Guthrie County IA	86 mph	75	Estimated	0
3:00 AM	Greene County IA	86 mph	75	Estimated	0
3:20 AM	Boone County IA	86 mph	75	Estimated	0
11:26 PM	Vermillion County IN	85 mph	74	Estimated	0
11:26 PM	Vermillion County IN	85 mph	74	Estimated	0
7:00 AM	Bureau County IL	84 mph	73	Measured	0
4:30 AM	Iowa County IA	81 mph	70	Measured	0
6:10 AM	Rock Island County IL	81 mph	70	Measured	0
7:14 AM	Woodford County IL	81 mph	70	Measured	0
2:45 AM	Guthrie County IA	81 mph	70	Estimated	0
3:05 AM	Dallas County IA	81 mph	70	Estimated	0
3:10 AM	Dallas County IA	81 mph	70	Estimated	0
3:25 AM	Polk County IA	81 mph	70	Estimated	0
3:45 AM	Polk County IA	81 mph	70	Estimated	0
5:15 AM	Johnson County IA	81 mph	70	Estimated	0
6:12 AM	Rock Island County IL	81 mph	70	Estimated	0
6:15 AM	Rock Island County IL	81 mph	70	Estimated	0
7:05 AM	Bureau County IL	81 mph	70	Estimated	0
5:29 PM	Rowan County NC	81 mph	70	Estimated	0
5:49 PM	Lyon County NV	81 mph	70	Estimated	0
2:28 AM	Carroll County IA	78 mph	68	Measured	0
2:23 AM	Carroll County IA	76 mph	66	Measured	0
1:50 AM	Crawford County IA	75 mph	65	Estimated	0
2:30 AM	Guthrie County IA	75 mph	65	Estimated	0
2:44 AM	Greene County IA	75 mph	65	Estimated	0
2:50 AM	Guthrie County IA	75 mph	65	Estimated	0
3:22 AM	Polk County IA	75 mph	65	Estimated	0
3:27 AM	Dallas County IA	75 mph	65	Estimated	0
3:28 AM	Dallas County IA	75 mph	65	Estimated	0
3:44 AM	Jasper County IA	75 mph	65	Estimated	0
4:10 AM	Poweshiek County IA	75 mph	65	Estimated	0
5:28 AM	Johnson County IA	75 mph	65	Estimated	0
5:45 AM	Muscatine County IA	75 mph	65	Estimated	0
6:25 AM	Henry County IL	75 mph	65	Estimated	0
6:35 AM	Henry County IL	75 mph	65	Estimated	0
7:04 AM	Bureau County IL	75 mph	65	Estimated	0
8:32 AM	Kankakee County IL	75 mph	65	Estimated	0
2:56 PM	Barnwell County SC	75 mph	65	Estimated	0
6:50 PM	Greenville County SC	75 mph	65	Estimated	0
10:50 PM	Bartholomew County IN	75 mph	65	Estimated	0
11:20 PM	Vermillion County IN	75 mph	65	Estimated	0
11:20 PM	Vermillion County IN	75 mph	65	Estimated	0
11:20 PM	Vermillion County IN	75 mph	65	Estimated	0
11:40 PM	Vigo County IN	75 mph	65	Estimated	0
11:50 PM	Putnam County IN	75 mph	65	Estimated	0
12:00 AM	Putnam County IN	75 mph	65	Estimated	0
12:00 AM	Putnam County IN	75 mph	65	Estimated	0
1:09 AM	Monona County IA	74 mph	64	Measured	0
3:28 AM	Polk County IA	74 mph	64	Measured	0
3:24 AM	Henry County IA	72 mph	63	Measured	0
3:26 AM	Polk County IA	72 mph	63	Measured	0
8:02 AM	Grundy County IL	72 mph	63	Measured	0
3:26 AM	Polk County IA	71 mph	62	Measured	0
3:16 AM	Polk County IA	70 mph	61	Measured	0
10:50 PM	Vermilion County IL	70 mph	61	Measured	0
1:00 AM	Dakota County NE	70 mph	61	Estimated	0
1:00 AM	Dakota County NE	70 mph	61	Estimated	0
1:05 AM	Woodbury County IA	70 mph	61	Estimated	0
2:05 AM	Carroll County IA	70 mph	61	Estimated	0
2:20 AM	Carroll County IA	70 mph	61	Estimated	0
2:25 AM	Carroll County IA	70 mph	61	Estimated	0
2:26 AM	Carroll County IA	70 mph	61	Estimated	0
2:35 AM	Guthrie County IA	70 mph	61	Estimated	0
2:43 AM	Greene County IA	70 mph	61	Estimated	0
2:44 AM	Greene County IA	70 mph	61	Estimated	0
2:59 AM	Dallas County IA	70 mph	61	Estimated	0
3:02 AM	Dallas County IA	70 mph	61	Estimated	0
3:08 AM	Boone County IA	70 mph	61	Estimated	0
3:09 AM	Dallas County IA	70 mph	61	Estimated	0
3:14 AM	Dallas County IA	70 mph	61	Estimated	0
3:15 AM	Dallas County IA	70 mph	61	Estimated	0
3:18 AM	Polk County IA	70 mph	61	Estimated	0
3:23 AM	Story County IA	70 mph	61	Estimated	0
3:28 AM	Dallas County IA	70 mph	61	Estimated	0
3:28 AM	Polk County IA	70 mph	61	Estimated	0
3:28 AM	Polk County IA	70 mph	61	Estimated	0
3:30 AM	Henry County IA	70 mph	61	Estimated	0
3:45 AM	Jasper County IA	70 mph	61	Estimated	0
4:24 AM	Poweshiek County IA	70 mph	61	Estimated	0
4:40 AM	McDonough County IL	70 mph	61	Estimated	0
4:45 AM	Iowa County IA	70 mph	61	Estimated	0
4:45 AM	Iowa County IA	70 mph	61	Estimated	0
4:50 AM	Fulton County IL	70 mph	61	Estimated	0
5:00 AM	Johnson County IA	70 mph	61	Estimated	0
5:10 AM	Fulton County IL	70 mph	61	Estimated	0
5:13 AM	Washington County IA	70 mph	61	Estimated	0
5:15 AM	Johnson County IA	70 mph	61	Estimated	0
5:16 AM	Johnson County IA	70 mph	61	Estimated	0
5:35 AM	Muscatine County IA	70 mph	61	Estimated	0
5:45 AM	Muscatine County IA	70 mph	61	Estimated	0
5:45 AM	Muscatine County IA	70 mph	61	Estimated	0
5:46 AM	Muscatine County IA	70 mph	61	Estimated	0
5:55 AM	Muscatine County IA	70 mph	61	Estimated	0

By state

Severe weather reports by state, July 21, 2008

Iowa	99	81 mph	19	1.75
Illinois	86	94 mph	28	2.75
Indiana	46	64 mph	7	1.75
South Carolina	39	61 mph	18	1.25
Georgia	30	—	9	1.25
Tennessee	16	—	6	1.00
Kentucky	10	—	4	1.00
Alabama	10	—	0	—
North Carolina	9	—	5	0.88
Pennsylvania	9	—	0	—
Missouri	7	—	11	2.00
Nevada	7	67 mph	8	1.25
Florida	4	—	3	1.00
South Dakota	4	64 mph	2	1.75
Nebraska	4	—	1	0.88
Wisconsin	3	—	3	0.88
Maryland	3	—	0	—
Ohio	2	—	1	1.75
Michigan	2	—	0	—
West Virginia	1	—	3	0.88
New York	1	—	1	1.00
Arizona	1	—	0	—
New Hampshire	1	—	0	—
Virginia	1	—	0	—

Counties with the most wind reports

Dallas CountyIA · 17 reports
Polk CountyIA · 13 reports
Muscatine CountyIA · 10 reports
Guthrie CountyIA · 9 reports
Henry CountyIL · 8 reports
Carroll CountyIA · 8 reports
Kankakee CountyIL · 8 reports
Jasper CountyIA · 7 reports
Rock Island CountyIL · 7 reports
Vigo CountyIN · 7 reports

Hail and tornadoes that day

129 hail reports, 4 of 2 inches or more; 4 tornadoes.

Largest hail, July 21, 2008

7:50 PM	Fulton County IL	2.75
8:00 PM	Fulton County IL	2.75
11:04 PM	Edgar County IL	2.50
8:26 PM	Grundy County MO	2.00
2:57 AM	Story County IA	1.75
5:45 PM	Pennington County SD	1.75
7:20 PM	Belmont County OH	1.75
7:35 PM	Lewis County MO	1.75
7:50 PM	Fulton County IL	1.75
8:01 PM	Fulton County IL	1.75
9:52 PM	Macon County IL	1.75
10:13 PM	Nodaway County MO	1.75
12:35 AM	Monroe County IN	1.75
8:15 PM	Adair County MO	1.50
1:14 AM	Dallas County IA	1.25
5:49 PM	Lyon County NV	1.25
6:20 PM	Bleckley County GA	1.25
6:45 PM	Greenville County SC	1.25
8:34 PM	Churchill County NV	1.25
10:50 PM	Edgar County IL	1.25
10:55 PM	Edgar County IL	1.25
3:07 AM	Story County IA	1.00
3:48 AM	Jasper County IA	1.00
12:13 PM	Wayne County NY	1.00
2:05 PM	Charleston County SC	1.00
2:08 PM	Charleston County SC	1.00
2:17 PM	Charleston County SC	1.00
2:45 PM	Clinton County KY	1.00
3:20 PM	Clay County FL	1.00
3:55 PM	Whitley County KY	1.00
4:59 PM	Pennington County SD	1.00
5:05 PM	Hamblen County TN	1.00
5:20 PM	Spartanburg County SC	1.00
6:26 PM	Polk County FL	1.00
7:30 PM	Knox County IL	1.00
7:40 PM	Oconee County GA	1.00
7:40 PM	Newton County GA	1.00
7:48 PM	Fulton County IL	1.00
7:48 PM	Fulton County IL	1.00
8:00 PM	Fulton County IL	1.00
8:00 PM	Fulton County IL	1.00
8:15 PM	Grundy County MO	1.00
8:27 PM	Churchill County NV	1.00
8:45 PM	Menard County IL	1.00
8:50 PM	Lewis County MO	1.00
9:45 PM	Macon County IL	1.00
9:47 PM	Nodaway County MO	1.00
10:33 PM	Brown County IN	1.00
10:50 PM	Sullivan County MO	1.00
11:13 PM	Vermillion County IN	1.00

EF0 tornado8:00 PM CDT
EF0 tornado8:23 PM CDT
EF0 tornado8:30 PM CDT
EF1 tornado10:34 PM CDT

2008 · 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.