Wednesday was One of the Most Active August Tornado Days on Record in the U.S.

Chris Dolce
Published: August 27,2016
Wednesday's tornado outbreak in Indiana and Ohio now ranks among the largest tornado days on record for the month of August coming in tied at #9.

Red circles show where there was a report of a tornado on Wednesday.

Though surveys are ongoing to determine the actual tornado count, there were nearly three dozen reports of tornadoes for the day. That's a large number for August, and they were all confined in a small corridor from central Indiana to northwest Ohio.

As of early Saturday morning, 21 tornadoes had been confirmed in Indiana and Ohio by the National Weather Service, including an EF3 in Kokomo, Indiana and an EF3 north of Woodburn, Indiana.
This total also includes three EF2, five EF1, and eleven EF0 tornadoes.
(MORE: Latest News on Wednesday's Tornadoes)

One of the Most Tornadic August Days Since 1950?

The most tornadoes for a single calendar day during the month of August dating to 1950 was Aug. 29, 2005, when Hurricane Katrina spawned 40, according to a tweet by Ian Livingston, co-founder of ustornadoes.com. Four other tropical cyclones are in the top 10 for the largest number of tornadoes in a single August day.

View image on Twitter

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Ian Livingston ✔ @islivingston

35 filtered tornado reports as of 10p today. Likely among largest tornado days on record in August. #inwx #ohwx

10:09 PM - 24 Aug 2016

• 68 68 Retweets
• 70

The rest of August's largest tornado days are dominated by states in the Midwest.
Leading the pack for the Midwest, and ranking as the fifth most active tornado day during the month, is Aug. 19, 2009. That day had 30 tornadoes across parts of five states, including Indiana and Ohio.

Cars are damaged in Kokomo, Indiana, by a tornado that hit the area on Wednesday, Aug. 24, 2016. (Twitter/TeeJay Crawford)

Since 21 tornadoes are confirmed from Wednesday, it cracks the top 10 for the largest number of tornadoes in a single August day across the U.S. dating to 1950.
On a state level, this was the largest August tornado day on record in Ohio. The National Weather Service in Northern Indiana and Cleveland have confirmed 11 tornadoes in Ohio so far.
The National Weather Service in Wilmington, Ohio, says that the most number of tornadoes for an August calendar day in Ohio was 7 on Aug. 28, 2006.
For Indiana, Wednesday ranks in the top 10 list for the most tornadoes during an outbreak in the state.
Weather Service offices in Indiana confirmed 10 tornadoes in that state on Wednesday. You can view those prelimary confirmations here and here.
The most August tornadoes in Indiana during a single event before Wednesday was 8, set earlier this month on Aug. 15. This beat the old record of 5 on Aug. 9, 1969.

Where Are August Tornadoes Most Common?

August as a whole is not a huge tornado-producing month, averaging about 72 twisters over the last 20 years. This ranks as the sixth most tornadic month of the year, on average.

Average number of tornadoes per month 1995-2014.

Tropical cyclones contribute to a significant number of the tornadoes we see in August, as illustrated by the list of the most tornadic days from Livingston above. About 17 percent of tornadoes during the month of August have been from tropical cyclones (1976-2005), according to severe weather expert Dr. Greg Forbes of The Weather Channel.
Although the probability of tornadoes is not particularly high in any one location of the United States, compared to say May or June, some areas are somewhat more favored than others.
The map below from NOAA shows the probability of tornadoes across the U.S. in late August.

Parts of the Midwest and Plains have slightly greater odds of tornadoes than most of the country. This is partially due to that region's proximity to stronger jet stream winds that are typically located closer to the Canadian border in summer.
In addition, there are slightly favored odds for tornadoes along the Gulf Coast and Florida from tropical storms and hurricanes.

PHOTOS: Wednesday's Tornadoes in the Midwest