Skip to comments.Birmingham, Huntsville part of nation's highest-risk tornado corridor, study by UAH researcher finds
Posted on 09/21/2013 2:05:19 PM PDT by Colonel Kangaroo
HUNTSVILLE, Alabama - The greatest risk of being impacted by a significant tornado in the United States is in a Deep South corridor that includes Huntsville and Birmingham, not the Great Plains region of Oklahoma and Kansas, according to a study co-authored by a University of Alabama in Huntsville researcher.
The research paper was written by Tim Coleman, an adjunct professor and researcher in the Earth Systems Science Center at UAH, and Grady Dixon, an associate professor of meteorology and climatology at Mississippi State University.
The paper is scheduled to be published by the American Meteorology Society's Weather and Forecasting, said Coleman, a researcher at UAH since 2005 who also worked nine years for the National Weather Service.
The research is significant, Coleman said, because it indicates that the true tornado alley in the United States is located in the Deep South rather than the long-held belief of the Great Plains.
"One of the (AMS) reviewers (of the research paper) said these results are very different than most people interpret as tornado alley," Coleman said today. "(The reviewer said) these results are important and should be communicated to the general public."
Coleman said the project also implemented a database seldom used in tornado research. Coleman and Dixon used only significant tornadoes (EF2 or stronger) from 1973-2011 in their research and measured the path lengths of those twisters to gauge the risk to a particular region.
The Deep South tornado alley, like a typical tornado, travels along a northeastern tract and includes cities such as Jackson, Miss., Columbus, Miss., Tuscaloosa, Birmingham, Jasper, Cullman, Huntsville and Decatur, Coleman said.
The most significant risk in the research that defined that tornado alley found significant tornadoes traveling 9 to 11 kilometers within 25 miles of a point. Beyond that corridor of highest risk, the northern half of Alabama, most of Mississippi as well as about half of Arkansas is in a range of 7 to 9 kilometer-long tornado paths.
View full sizeUAH adjunct professor and researcher Tim Coleman. (Submitted photo)
The most significant risk in the Great Plains is an area making up most of Oklahoma, including Oklahoma City, with a range of tornadoes 5 to 7 kilometers in length, the research found.
The compelling reason to study the path lengths of tornadoes, Coleman said, is because the longer the path, the more impact it has on a region.
Significant tornadoes - rather than all tornadoes - were used because significant tornadoes have more impact and create more risk and that while technology has allowed for better identification of smaller tornadoes over the years, the number of significant tornadoes has remained consistent, Coleman said.
The research found that Deep South tornadoes typically have longer paths than those in the Great Plains because they are traveling at a faster rate, Coleman said.
"That still makes more risk because you're covering more ground," Coleman said.
The reason the project began with data in 1973, Coleman said, is because that was the first year the Fujita scale for measuring tornadoes was used. Before that, Coleman said, tornado ratings were not precise and leaned heavily on media reports. The end date of the research window coincided with the beginning of the research project, he said.
The research also took into consideration the record tornado outbreak in Alabama and Mississippi on April 27, 2011. To make sure the research was not skewed by the unprecedented day in 2011, Coleman and Dixon also studied the research from 1973-2010. That research found that while the Deep South tornado alley was less fearsome, it nevertheless remained in place.
In excluding the 2011 storms, virtually the entire state of Mississippi as well as the northern half of Alabama had significant tornadoes in the 5 to 7 kilometers path range. There were also regions in the northern halves of both states that saw that path range increase to 7 to 9 kilometers.
Meanwhile, the data remained largely the same in the Great Plains in omitting 2011.
Coleman said he and Dixon had "a hunch" that the tornado risk in the Deep South might be greater than traditionally thought when they began their project.
"Just because it's a guy from the University of Alabama in Huntsville and a guy from Mississippi State University, we didn't do anything to make the data look the way we wanted," Coleman said. "We had no idea what was going to come out."
The researchers are also anticipating criticism for their findings.
"We anticipate there will be some challenges to this paper," Coleman said. "We've already done some calculations to check our own work. We're confident about the results and feel confident about answering any challenges that may come up."
Economic impact is also a possible side effect of the research. Coleman said he's heard concerns that the findings could discourage businesses from coming to the regions where the tornado risk is considered higher than anywhere else in the country. That shouldn't be a factor, he said, because even in the highest risk areas, the chances of a home or business being impacted by a tornado is less than 1 percent.
"That would imply that even in the areas that have just about the highest risk in the United States, the chance of a significant tornado hitting any specific spot inside that area is 0.5 percent each year," Coleman said. "It would tend to happen once every 200 years."
Coleman also pointed to research he did following the April 27, 2011 tornadoes that only about 1 percent of Alabama was hit by a tornado touchdown.
The benefits could be an influx of research dollars to the Deep South that typically are funneled to the Great Plains. The University of Alabama in Huntsville is also constructing the Severe Weather Institute Radar and Lightning Laboratory (SWIRLL) to enhance research.
"Very little research money is coming to the southeast at this point to study tornadoes," Coleman said. "This could be something that the powers that be - whether it's the National Science Foundation or people in state government, it could be something they look at -- if we're in tornado alley, maybe we need to do a little more in terms of research here.
"There are issues that I and two or three of my colleagues at UAH have been looking at and we don't have the funding to do what we need to do right now."
I’ve been surprised over the last decade that mountains/hilliness aren’t more effective in disrupting tornadoes.
When I first saw that, I remembered my old geography professor telling us that exact same thing way back in the early 70s.
Cute, but Moore has hard evidence of multiple significant strikes. Not statistical what-iffery.
Knew this back in ‘74.
Got to witness Athens, Al get destroyed.
Got to see it again in 2011.
The got hit in 2012.
I think there might be some scientific speculation that rugged terrain might disrupt weaker tornadoes more than strong supercell storms. I know that one of the bad storms of April 2011, the EF-4 Ringgold Georgia-Apison Tennessee tornado, went over a ridge before killing 20 people.
Already knew this. Have been through several F5s. Our local tv stations go to full time storm coverage when we are under a watch/warning . Facebook was our source for info during the last one. Don’t know what we would have done without it when we were without power for over a week. I kept my iPhone charged by using my car battery.
Did you get hit by the one in 1989? Think that was the year.
Oh Great. Not that I hadn’t already figured it out. As a citizen of Rocket City U.S.A. . . . I knew it was bad. I’d love to get a shelter. But one outfit in town is being sued for putting in sub-standard shelters. Great, spend 10K or whatever and think your family is protected when they really aren’t. I hate torando warnings. The early closing of the schools. I just hope & pray at this point, all ya can do. We WILL build a safe room in our next house. After ‘08 we’ve been in limbo to rebuild and with a kid just second year college and one in 11th grade . . . we couldn’t just up and move either and disrupt their lives . . . we have some property in TN we’d like to build on but on hold for another 18 months. Safe room, will build it big enough and large enough for some bunk beds, a sofa maybe, plenty of supplies, a bookcase for photo albums. Until then . . . prayers.
Yep, I use my Diesel cars to keep a small bank of batteries charged for various inverters when we have grid failures.
(Plus I keep a tactical reserve of Diesel fuel for various "emergencies").
That looks nasty for N. Ala.
Buy a place from the 50’s with a Bomb Shelter. ;-)
We moved here in ‘92. I had no idea. Until some co-workers at Boeing on the space station project bought a photo album to work. Off all the cars off Airport Road with the big spray painted X’s on them to indicate they had been searched. I was like Uh-Oh.
yep we were without power for a full week. Charged phones in car. Neighbor used a couple of 100’ extension cords and kept our garage freezer going and the neighbor on his other side going. We managed to escape far enough into TN to buy a little 7” RCA ac/dc digital tv to keep up with the morning EMA updates. Long week. Cold showers. Pop tarts, peanut butter sandwiches, crackers. Water.
Many find that those inexpensive solar powered garden lights work fine as night lights all around the house.
Yep that is what we’ll use next time. Just installed 24 of them this past week and ditched the electric ones which had been abused over the years with the kids playing soccer and hitting baseballs and whacking them accidentally . . . :)
The current units are quite efficient as they use a chip to institute a high frequency capacitor charging stratergy to limit current to the LED ilo a power dissipating resistor.
Thanks. I had some photo Double A’s just the other day my husband put on the charger, after I had put them on with the message from the camera, charge the batteries, after charging them full . . . so he set them to completely run-down discharge then re-charge . . . seems this process was quite lengthy, don’t know why but it seemed to have worked. For some reason, me and re-chargeable batteries don’t get along. :)