The severe wind outbreak of July 7, 1991
306 wind reportsPennsylvania, Michigan, Iowa and 12 more states
306 damaging wind reports across 15 states between 3:00 AM and 12:50 AM the next day CDT, 17 of them 65 knots (75 mph) or stronger. 50 hail reports and 9 tornadoes the same day.
Watch the day unfoldSevere wind day · July 7, 1991
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
- 306
- on Sunday, July 7, 1991
- 75 mph or more
- 17
- 2 of 86 mph (75 knots) or more
- Strongest measured gust
- —
- No measured gust reported
- Measured
- 0
- reports with an instrument reading; the rest are estimates from damage
- Killed by wind
- 1
- 22 injured
- Counties reporting
- 171
- in 15 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.
| 12:15 PM | Sussex County DE | 115 mph | Estimated |
| 9:20 AM | Lyon County IA | 86 mph | Estimated |
| 10:10 AM | O'Brien County IA | 85 mph | Estimated |
| 6:15 PM | Ionia County MI | 85 mph | Estimated |
| 7:45 PM | Oakland County MI | 85 mph | Estimated |
| 10:20 AM | Clay County IA | 84 mph | Estimated |
| 5:53 PM | Kent County MI | 84 mph | Estimated |
| 7:39 PM | Washtenaw County MI | 83 mph | Estimated |
| 8:50 AM | Lincoln County SD | 81 mph | Estimated |
| 3:35 PM | Jefferson County WI | 81 mph | Estimated |
| 9:27 AM | Sioux County IA | 79 mph | Estimated |
| 9:30 AM | Sioux County IA | 79 mph | Estimated |
| 10:54 AM | Chester County PA | 79 mph | Estimated |
| 10:35 AM | Humboldt County IA | 77 mph | Estimated |
| 10:30 AM | Palo Alto County IA | 75 mph | Estimated |
| 10:45 AM | Palo Alto County IA | 75 mph | Estimated |
| 12:50 PM | York County PA | 75 mph | Estimated |
| 4:08 PM | Milwaukee County WI | 72 mph | Estimated |
| 8:20 PM | Macomb County MI | 72 mph | Estimated |
| 11:59 AM | Cerro Gordo County IA | 71 mph | Estimated |
| 6:40 PM | Eaton County MI | 71 mph | Estimated |
| 6:50 PM | Clinton County MI | 71 mph | Estimated |
| 6:55 PM | Eaton County MI | 71 mph | Estimated |
| 7:05 PM | Jackson County MI | 71 mph | Estimated |
| 8:45 AM | Turner County SD | 70 mph | Estimated |
| 10:30 AM | Pocahontas County IA | 70 mph | Estimated |
| 10:50 AM | Palo Alto County IA | 70 mph | Estimated |
| 11:45 AM | Franklin County PA | 70 mph | Estimated |
| 11:58 AM | Mitchell County IA | 70 mph | Estimated |
| 12:45 PM | Fillmore County MN | 70 mph | Estimated |
| 6:10 PM | Berrien County MI | 70 mph | Estimated |
| 7:11 PM | Livingston County MI | 70 mph | Estimated |
| 8:00 PM | Wayne County MI | 70 mph | Estimated |
| 8:15 PM | Livingston County MI | 70 mph | Estimated |
| 9:15 PM | Wood County OH | 70 mph | Estimated |
| 9:45 PM | Ashtabula County OH | 70 mph | Estimated |
| 10:15 AM | Cherokee County IA | 69 mph | Estimated |
| 3:05 PM | Dane County WI | 68 mph | Estimated |
| 1:30 PM | Kent County MD | 67 mph | Estimated |
| 5:41 PM | Ottawa County MI | 66 mph | Estimated |
| 6:00 PM | Ottawa County MI | 66 mph | Estimated |
| 10:45 AM | Chester County PA | 64 mph | Estimated |
| 11:30 AM | Cerro Gordo County IA | 64 mph | Estimated |
| 3:20 PM | Jefferson County WI | 64 mph | Estimated |
| 12:30 PM | Baltimore County MD | 63 mph | Estimated |
| 12:45 PM | Baltimore County MD | 63 mph | Estimated |
| 1:00 PM | Baltimore County MD | 63 mph | Estimated |
| 5:58 PM | Kent County MI | 63 mph | Estimated |
| 11:18 AM | Burlington County NJ | 61 mph | Estimated |
| 6:53 PM | Cass County MI | 61 mph | Estimated |
| 7:00 PM | Cass County MI | 61 mph | Estimated |
| 8:25 AM | Hutchinson County SD | 60 mph | Estimated |
| 9:00 AM | Lincoln County SD | 60 mph | Estimated |
| 10:48 AM | Chester County PA | 60 mph | Estimated |
| 11:04 AM | Delaware County PA | 60 mph | Estimated |
| 11:43 AM | Burlington County NJ | 60 mph | Estimated |
| 3:35 PM | Waukesha County WI | 60 mph | Estimated |
| 3:40 PM | Washington County WI | 60 mph | Estimated |
| 5:40 PM | Ottawa County MI | 60 mph | Estimated |
| 6:20 PM | Calhoun County MI | 60 mph | Estimated |
| 6:40 PM | Clinton County MI | 60 mph | Estimated |
| 6:50 PM | Elkhart County IN | 60 mph | Estimated |
| 6:50 PM | Calhoun County MI | 60 mph | Estimated |
| 7:15 PM | Branch County MI | 60 mph | Estimated |
| 7:25 PM | Washtenaw County MI | 60 mph | Estimated |
| 7:30 PM | Livingston County MI | 60 mph | Estimated |
| 7:35 PM | Hillsdale County MI | 60 mph | Estimated |
| 7:52 PM | Monroe County MI | 60 mph | Estimated |
| 8:00 PM | Lenawee County MI | 60 mph | Estimated |
| 8:05 PM | Macomb County MI | 60 mph | Estimated |
| 8:08 PM | Macomb County MI | 60 mph | Estimated |
| 8:15 PM | St. Clair County MI | 60 mph | Estimated |
| 8:15 PM | St. Clair County MI | 60 mph | Estimated |
| 8:15 PM | Oakland County MI | 60 mph | Estimated |
| 8:15 PM | Washtenaw County MI | 60 mph | Estimated |
| 8:20 PM | Wayne County MI | 60 mph | Estimated |
| 8:20 PM | Lenawee County MI | 60 mph | Estimated |
| 8:30 PM | Monroe County MI | 60 mph | Estimated |
| 8:30 PM | Wayne County MI | 60 mph | Estimated |
| 8:47 PM | Lucas County OH | 60 mph | Estimated |
| 11:35 AM | Salem County NJ | 59 mph | Estimated |
| 1:35 PM | Cape May County NJ | 59 mph | Estimated |
| 9:25 AM | Plymouth County IA | 58 mph | Estimated |
| 9:45 AM | Sioux County IA | 58 mph | Estimated |
| 9:50 AM | Cherokee County IA | 58 mph | Estimated |
| 9:55 AM | O'Brien County IA | 58 mph | Estimated |
| 9:58 AM | Clay County IA | 58 mph | Estimated |
| 10:30 AM | Pocahontas County IA | 58 mph | Estimated |
| 10:30 AM | Hancock County IA | 58 mph | Estimated |
| 11:00 AM | Kossuth County IA | 58 mph | Estimated |
| 11:11 AM | Winnebago County IA | 58 mph | Estimated |
| 11:20 AM | Hancock County IA | 58 mph | Estimated |
| 11:38 AM | Cerro Gordo County IA | 58 mph | Estimated |
| 11:40 AM | Hancock County IA | 58 mph | Estimated |
| 11:43 AM | Franklin County IA | 58 mph | Estimated |
| 11:51 AM | Worth County IA | 58 mph | Estimated |
| 11:51 AM | Worth County IA | 58 mph | Estimated |
| 12:00 PM | Mitchell County IA | 58 mph | Estimated |
| 12:00 PM | Franklin County IA | 58 mph | Estimated |
| 12:00 PM | Floyd County IA | 58 mph | Estimated |
By state
| Pennsylvania | 69 | — |
| Michigan | 64 | — |
| Iowa | 41 | — |
| Wisconsin | 33 | — |
| Ohio | 25 | — |
| New Jersey | 15 | — |
| Indiana | 13 | — |
| New York | 13 | — |
| Maryland | 12 | — |
| West Virginia | 9 | — |
| Virginia | 5 | — |
| South Dakota | 4 | — |
| Illinois | 1 | — |
| Minnesota | 1 | — |
| Delaware | 1 | — |
| Montana | 0 | — |
Counties with the most wind reports
- Erie CountyPA · 9 reports
- Chester CountyPA · 6 reports
- Crawford CountyPA · 6 reports
- Calhoun CountyMI · 5 reports
- Cambria CountyPA · 5 reports
- Jefferson CountyWI · 5 reports
- Oakland CountyMI · 4 reports
- Burlington CountyNJ · 4 reports
- Dane CountyWI · 4 reports
- Waukesha CountyWI · 4 reports
Hail and tornadoes that day
50 hail reports, 2 of 2 inches or more; 9 tornadoes.
| 6:50 AM | Minnehaha County SD | 3.50 |
| 5:15 PM | Will County IL | 2.75 |
| 3:10 AM | Clayton County IA | 1.75 |
| 3:20 AM | Delaware County IA | 1.75 |
| 1:00 PM | Harford County MD | 1.75 |
| 4:55 PM | Grundy County IL | 1.75 |
| 8:00 PM | Jasper County IN | 1.75 |
| 8:00 PM | Newton County IN | 1.75 |
| 8:30 PM | Pulaski County IN | 1.75 |
| 9:25 PM | Kankakee County IL | 1.75 |
| 12:10 AM | Kosciusko County IN | 1.75 |
| 12:20 AM | Starke County IN | 1.75 |
| 6:00 AM | McCook County SD | 1.50 |
| 1:00 PM | Anne Arundel County MD | 1.50 |
| 10:40 PM | Cook County IL | 1.50 |
| 1:00 AM | Mercer County PA | 1.00 |
| 3:00 AM | Wibaux County MT | 1.00 |
| 7:15 AM | Minnehaha County SD | 1.00 |
| 11:45 AM | Middlesex County NJ | 1.00 |
| 12:07 PM | Huntingdon County PA | 1.00 |
| 4:00 PM | Perry County OH | 1.00 |
| 4:05 PM | Racine County WI | 1.00 |
| 5:20 PM | Mason County MI | 1.00 |
| 5:20 PM | Ottawa County MI | 1.00 |
| 5:20 PM | Ottawa County MI | 1.00 |
| 5:42 PM | Lake County IN | 1.00 |
| 6:00 PM | Loudoun County VA | 1.00 |
| 6:45 PM | Montgomery County MD | 1.00 |
| 7:10 PM | Livingston County IL | 1.00 |
| 7:19 PM | Kankakee County IL | 1.00 |
| 7:35 PM | Kankakee County IL | 1.00 |
| 8:22 PM | Fulton County OH | 1.00 |
| 12:50 AM | Starke County IN | 1.00 |
| 7:30 PM | Tucker County WV | 0.88 |
| 5:25 AM | Madison County NY | 0.75 |
| 8:30 AM | Yankton County SD | 0.75 |
| 9:40 AM | Plymouth County IA | 0.75 |
| 10:10 AM | Montgomery County PA | 0.75 |
| 10:45 AM | Hunterdon County NJ | 0.75 |
| 11:25 AM | Camden County NJ | 0.75 |
| 1:30 PM | Montgomery County MD | 0.75 |
| 2:10 PM | Montgomery County MD | 0.75 |
| 2:37 PM | St. Louis County MN | 0.75 |
| 5:55 PM | Grundy County IL | 0.75 |
| 6:30 PM | Montgomery County MD | 0.75 |
| 9:45 PM | Knox County OH | 0.75 |
| 10:00 PM | Trumbull County OH | 0.75 |
| 11:07 PM | Beaver County PA | 0.75 |
| 11:10 PM | Venango County PA | 0.75 |
| 11:50 PM | Geauga County OH | 0.75 |
- F1 tornado12:10 PM CDT
- F0 tornado12:20 PM CDT
- F0 tornado1:23 PM CDT
- F0 tornado2:42 PM CDT
- F0 tornado5:30 PM CDT
- F0 tornado5:45 PM CDT
- F0 tornado6:05 PM CDT
- F2 tornado7:00 PM CDT
- F0 tornado8:00 PM CDT
1991 · 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.