What is being called the Great Quad-State Tornado has been given a preliminary rating of EF4 with peak winds of 190 mph (making it a high-end EF4). This is the 2nd EF4 tornado in the U.S. in 2021 and the strongest tornado of the year. The other EF4 tornado occurred e tornado occurred the night of March 25. It was a low-end EF4 tornado with 170 mph that caused major damage in Newnan, Georgia during the overnight hours, leveling homes and killing one person.
This is preliminary. We know there has been a 128-mile path and that may be expanded. They are still trying to determine if there are breaks in the damage path from NE Arkansas to S. of Cincinnati.
It’s interesting to compare Friday night’s tornado to the March 1925 Tri-State Tornado. The “Tri-State” Tornado of March 18, 1925 killed 695 people as it raced along at 60-73 mph in a roughly 243-mile-long track across parts of Missouri, Illinois and Indiana, producing F5 damage. The path length is based on a peer-reviewed forensic research paper by former SPC forecaster Bob Johns and colleagues. The death toll is an estimate based on the work of Grazulis (1993); older references have different counts. This event also holds the known record for most tornado fatalities in a single city or town: at least 234 at Murphysboro IL. The deadliest of the modern era (since 1950) was on 22 May 2011, when a large EF5 tornado crossed Joplin, MO, causing 158 direct fatalities. The 25 deadliest tornadoes on record are listed here.
Both the Quad-State Tornado and the Tri-State Tornado crossed the Mississippi River. Both tornadoes occurred in winter and were wide. The Quad-State tornado was at least 3/4-mile wide at one point. Both tornadoes were relatively fast-moving. The Tri-State Tornado was estimated to have moved at up to 73 mph.
There were no watches or warning in 1925, no media, no cell phones and the death toll was very high – estimated to be 695. The death toll for the Quad-State tornado was no doubt lower because of the advance outlooks, watches and warnings. The trouble is that a strong EF4 or Ef5 tornado is often not survivable above ground. We saw places where homes were gone – all that was left was the concrete slab foundation.
It will take a great effort for the National Weather Service to survey the entire length of this tornado and to survey the other areas with tornado damage. There will be scientific papers written about this twister. It’ll be studied by Emergency Management. We can’t stop tornadoes, but we can give the best warning we can and we can support organizations like the Red Cross and Salvation Army that move in to provide relief to those who are hurting.
I think the Quad-State tornado will be rated EF4 or even EF5. We don’t know exactly how long the path is, or even if it’s a continuous path, but several knowledgeable people I would trust said there is a good chance it’s over 200 miles…crossing NE Arkansas, a small portion of the SE Missouri Bootheel, a small part of far NW Tennessee and then a longer path through Western and Central Kentucky. It crossed both the Mississippi and Kentucky/Tennessee rivers. It was also well forecast by the NWS – from the early outlooks to the watches and warnings night of, it was an effort worthy of noting. The tornado killed 7 children on just one street.
Comparing the Storm Prediction Center Severe Weather Forecast to what actually happened. I think this was a good forecast. Radar image of the massive tornado moving into Mayfield KY. At the Mayfield Candle Factory – there were 110 people in the building. 93 were brought out alive. There were 8 fatalities. Nine are “unaccounted for”. Photo traveled 130 miles in the tornado (the distance from Grand Rapids to Detroit is roughly 141 miles). Before and after pictures of tornado damage.