The severe wind outbreak of May 17, 2017
302 wind reportsIowa, Wisconsin, Illinois and 5 more states
302 damaging wind reports across 8 states between 1:10 AM and 12:33 AM the next day CDT, 31 of them 65 knots (75 mph) or stronger; the strongest measured gust was 89 mph in Delaware County, IA. 89 hail reports and 16 tornadoes the same day.
Watch the day unfoldSevere wind day · May 17, 2017
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.
The day in numbers
- Wind reports
- 302
- on Wednesday, May 17, 2017
- 75 mph or more
- 31
- 3 of 86 mph (75 knots) or more
- Strongest measured gust
- 89 mph
- 77 knots, Delaware County, IA
- Measured
- 58
- reports with an instrument reading; the rest are estimates from damage
- Killed by wind
- 1
- 1 injured
- Counties reporting
- 119
- in 8 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.
| 6:30 PM | Winnebago County IL | 96 mph | Estimated |
| 10:19 PM | Lee County IL | 90 mph | Estimated |
| 6:28 PM | Delaware County IA | 89 mph | Measured |
| 10:37 PM | McHenry County IL | 85 mph | Estimated |
| 7:19 PM | Grant County WI | 81 mph | Measured |
| 1:08 PM | Buena Vista County IA | 81 mph | Estimated |
| 4:27 PM | Washington County IA | 81 mph | Estimated |
| 5:35 PM | Iowa County IA | 81 mph | Estimated |
| 5:57 PM | Benton County IA | 81 mph | Estimated |
| 6:44 PM | Rock County WI | 81 mph | Estimated |
| 6:47 PM | Rock County WI | 81 mph | Estimated |
| 7:05 PM | Marathon County WI | 81 mph | Estimated |
| 7:45 PM | Lincoln County WI | 81 mph | Estimated |
| 9:52 PM | Lee County IL | 81 mph | Estimated |
| 10:20 PM | Shawano County WI | 81 mph | Estimated |
| 10:30 PM | Sheboygan County WI | 81 mph | Estimated |
| 10:39 PM | Walworth County WI | 81 mph | Estimated |
| 7:04 PM | Dubuque County IA | 78 mph | Measured |
| 3:40 AM | Rogers County OK | 75 mph | Estimated |
| 4:21 PM | Kossuth County IA | 75 mph | Estimated |
| 4:40 PM | Washington County IA | 75 mph | Estimated |
| 5:40 PM | Butler County IA | 75 mph | Estimated |
| 5:45 PM | Butler County IA | 75 mph | Estimated |
| 6:25 PM | Linn County IA | 75 mph | Estimated |
| 6:30 PM | Winnebago County IL | 75 mph | Estimated |
| 6:31 PM | Winnebago County IL | 75 mph | Estimated |
| 6:51 PM | Delaware County IA | 75 mph | Estimated |
| 7:01 PM | Jefferson County WI | 75 mph | Estimated |
| 7:01 PM | Walworth County WI | 75 mph | Estimated |
| 8:34 PM | Vilas County WI | 75 mph | Estimated |
| 8:45 PM | Clinton County IA | 75 mph | Estimated |
| 3:50 PM | Guthrie County IA | 74 mph | Estimated |
| 6:57 PM | Dubuque County IA | 72 mph | Measured |
| 7:31 PM | Grant County WI | 71 mph | Measured |
| 12:05 AM | Kendall County IL | 71 mph | Measured |
| 5:46 PM | Benton County IA | 70 mph | Measured |
| 5:53 PM | Benton County IA | 70 mph | Measured |
| 5:53 PM | Black Hawk County IA | 70 mph | Measured |
| 6:15 PM | Floyd County IA | 70 mph | Measured |
| 6:15 PM | Iowa County IA | 70 mph | Measured |
| 6:21 PM | Linn County IA | 70 mph | Measured |
| 6:53 PM | Clayton County IA | 70 mph | Measured |
| 3:28 AM | Tulsa County OK | 70 mph | Estimated |
| 1:08 PM | Buena Vista County IA | 70 mph | Estimated |
| 1:08 PM | Buena Vista County IA | 70 mph | Estimated |
| 1:08 PM | Buena Vista County IA | 70 mph | Estimated |
| 3:43 PM | Clarke County IA | 70 mph | Estimated |
| 3:55 PM | Van Buren County IA | 70 mph | Estimated |
| 4:10 PM | Madison County IA | 70 mph | Estimated |
| 4:18 PM | Polk County IA | 70 mph | Estimated |
| 4:18 PM | Warren County IA | 70 mph | Estimated |
| 4:19 PM | Polk County IA | 70 mph | Estimated |
| 4:25 PM | Polk County IA | 70 mph | Estimated |
| 4:25 PM | Polk County IA | 70 mph | Estimated |
| 4:39 PM | Jasper County IA | 70 mph | Estimated |
| 5:12 PM | Marshall County IA | 70 mph | Estimated |
| 5:30 PM | Grundy County IA | 70 mph | Estimated |
| 5:47 PM | Butler County IA | 70 mph | Estimated |
| 5:47 PM | Black Hawk County IA | 70 mph | Estimated |
| 5:53 PM | Butler County IA | 70 mph | Estimated |
| 6:08 PM | Benton County IA | 70 mph | Estimated |
| 6:10 PM | Linn County IA | 70 mph | Estimated |
| 6:28 PM | Linn County IA | 70 mph | Estimated |
| 6:36 PM | Rock County WI | 70 mph | Estimated |
| 6:45 PM | Winneshiek County IA | 70 mph | Estimated |
| 6:52 PM | Delaware County IA | 70 mph | Estimated |
| 7:00 PM | Clayton County IA | 70 mph | Estimated |
| 7:00 PM | Jefferson County WI | 70 mph | Estimated |
| 7:10 PM | Grant County WI | 70 mph | Estimated |
| 7:20 PM | Waukesha County WI | 70 mph | Estimated |
| 7:22 PM | Waukesha County WI | 70 mph | Estimated |
| 7:24 PM | Grant County WI | 70 mph | Estimated |
| 8:35 PM | Eau Claire County WI | 70 mph | Estimated |
| 8:47 PM | Columbia County WI | 70 mph | Estimated |
| 10:28 PM | Sheboygan County WI | 70 mph | Estimated |
| 5:12 PM | Marshall County IA | 69 mph | Measured |
| 5:13 PM | Marshall County IA | 69 mph | Measured |
| 3:55 PM | Adair County IA | 69 mph | Estimated |
| 4:10 PM | Dallas County IA | 69 mph | Estimated |
| 4:20 PM | Washington County IA | 69 mph | Estimated |
| 4:25 PM | Boone County IA | 69 mph | Estimated |
| 5:03 PM | Marshall County IA | 69 mph | Estimated |
| 5:14 PM | Marshall County IA | 69 mph | Estimated |
| 5:45 PM | Scotland County MO | 69 mph | Estimated |
| 6:05 PM | Ogle County IL | 69 mph | Estimated |
| 6:07 PM | Monroe County WI | 69 mph | Estimated |
| 6:08 PM | Ogle County IL | 69 mph | Estimated |
| 6:15 PM | Winnebago County IL | 69 mph | Estimated |
| 6:17 PM | Winnebago County IL | 69 mph | Estimated |
| 6:48 PM | Johnson County IA | 69 mph | Estimated |
| 7:00 PM | Delaware County IA | 69 mph | Estimated |
| 8:35 PM | Henry County IL | 69 mph | Estimated |
| 10:23 PM | LaSalle County IL | 69 mph | Estimated |
| 10:52 PM | DeKalb County IL | 69 mph | Estimated |
| 11:00 PM | LaSalle County IL | 69 mph | Estimated |
| 5:25 PM | Poweshiek County IA | 68 mph | Measured |
| 6:20 PM | Mitchell County IA | 68 mph | Measured |
| 6:35 PM | Washington County IA | 67 mph | Measured |
| 3:37 AM | Tulsa County OK | 66 mph | Measured |
| 1:57 PM | Wood County WI | 66 mph | Measured |
By state
Counties with the most wind reports
- Polk CountyIA · 16 reports
- Marshall CountyIA · 10 reports
- Butler CountyIA · 7 reports
- Dallas CountyIA · 6 reports
- Monroe CountyWI · 6 reports
- Black Hawk CountyIA · 6 reports
- Winnebago CountyIL · 6 reports
- Grant CountyWI · 6 reports
- Trempealeau CountyWI · 6 reports
- Jefferson CountyWI · 5 reports
Hail and tornadoes that day
89 hail reports, 1 of 2 inches or more; 16 tornadoes.
| 6:37 PM | Henry County IA | 2.00 |
| 3:05 PM | Freeborn County MN | 1.75 |
| 4:20 PM | Henry County IA | 1.75 |
| 4:45 PM | Louisa County IA | 1.75 |
| 5:23 PM | Muscatine County IA | 1.75 |
| 5:42 PM | Jefferson County IA | 1.75 |
| 6:17 PM | Winnebago County IL | 1.75 |
| 6:37 PM | Henry County IA | 1.75 |
| 6:40 PM | Henry County IA | 1.75 |
| 7:40 PM | Louisa County IA | 1.75 |
| 6:46 PM | Washington County IA | 1.50 |
| 7:54 PM | Wabasha County MN | 1.50 |
| 10:25 PM | Boone County IL | 1.50 |
| 10:44 PM | Peoria County IL | 1.50 |
| 7:02 AM | Lincoln County KS | 1.25 |
| 3:00 PM | Freeborn County MN | 1.25 |
| 4:10 PM | Freeborn County MN | 1.25 |
| 4:28 PM | Henry County IA | 1.25 |
| 6:52 AM | Mitchell County KS | 1.00 |
| 2:14 PM | Douglas County NE | 1.00 |
| 2:34 PM | Douglas County NE | 1.00 |
| 2:48 PM | Dallas County IA | 1.00 |
| 2:55 PM | Dallas County IA | 1.00 |
| 3:03 PM | Dallas County IA | 1.00 |
| 3:10 PM | Polk County IA | 1.00 |
| 3:15 PM | Black Hawk County IA | 1.00 |
| 3:16 PM | Columbia County WI | 1.00 |
| 3:18 PM | Polk County IA | 1.00 |
| 3:30 PM | Martin County MN | 1.00 |
| 3:30 PM | Martin County MN | 1.00 |
| 4:15 PM | Monroe County IA | 1.00 |
| 4:21 PM | Dubuque County IA | 1.00 |
| 4:29 PM | Houston County MN | 1.00 |
| 4:29 PM | Monroe County IA | 1.00 |
| 4:47 PM | Winona County MN | 1.00 |
| 4:52 PM | Louisa County IA | 1.00 |
| 4:55 PM | Winona County MN | 1.00 |
| 5:05 PM | Floyd County IA | 1.00 |
| 5:11 PM | Muscatine County IA | 1.00 |
| 5:40 PM | Scott County IA | 1.00 |
| 5:49 PM | Wapello County IA | 1.00 |
| 5:52 PM | Iowa County IA | 1.00 |
| 6:16 PM | Van Buren County IA | 1.00 |
| 6:45 PM | Rock County WI | 1.00 |
| 6:48 PM | Wood County WI | 1.00 |
| 6:51 PM | Rock County WI | 1.00 |
| 6:52 PM | Wood County WI | 1.00 |
| 7:15 PM | Racine County WI | 1.00 |
| 7:31 PM | Houston County MN | 1.00 |
| 7:34 PM | Muscatine County IA | 1.00 |
- EF1 tornado1:24 AM CDT
- EF0 tornado2:10 PM CDT
- EF0 tornado2:42 PM CDT
- EF1 tornado3:48 PM CDT
- EF1 tornado4:16 PM CDT
- EF0 tornado4:29 PM CDT
- EF0 tornado5:04 PM CDT
- EF1 tornado5:21 PM CDT
- EF1 tornado6:36 PM CDT
- EF0 tornado6:50 PM CDT
- EF0 tornado7:35 PM CDT
- EF1 tornado7:44 PM CDT
- EF1 tornado8:00 PM CDT
- EF1 tornado8:44 PM CDT
- EF2 tornado9:20 PM CDT
- EF1 tornado10:21 PM CDT
2017 · 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.