Wednesday, September 14, 2011

New Tornado Statistics... Arkansas IS in Tornado Alley

We traditionally think of tornado alley as in the plains, but I think it's fair to say Arkansas is not only a part of it, but also in the heart of it according to new statistics released by the National Weather Service.

The new 30 year average indicates the annual number of tornadoes in Arkansas increased from 26 to 33.  Meteorologist John Robinson with the National Weather Service office in North Little Rock says there are 2 likely causes for the increase.  First, there is more public awareness of severe weather, thus people are more likely to report tornadoes.  The second reason is due to the National Weather Service increased efforts to verify tornadoes by going our and examining storm damage.

Take a look at this first map...

Average number of tornadoes annually by state
It's easy to see most states in tornado alley have more tornadoes than Arkansas over the past 30 years, but is this an accurate indicator of historic tornadic activity?

Now look at this 2nd map....

Average number of tornadoes per 10,000 square miles
It's logical that Texas would have more tornadoes than all states because of its size.  However, if you look at the number per 10,000 square miles, Arkansas has more twisters than the Lone Star state.

A few years ago, meteorologist Ashley Walker worked on some important research.  He found out that portions of Arkansas are in what's called "Fatality Alley" meaning there are more deaths caused by tornadoes in sections of Arkansas, Mississippi, Tennessee, and Alabama than any other place in the country.

Research from Meteorologist Walker Ashley with Northern Illinois University
If the new statistics from the National Weather Service and research from Walker Ashley aren't a wake up call, I don't know what is?    Here are a few of reasons portions of the mid south are in "fatality alley"

  • Mobile home density. The NIU meteorologist said 44 percent of all fatalities during tornadoes occur in mobile homes, compared to 25 percent in permanent houses. The southeast United States has the highest percentage of mobile-home stock compared with any other region east of the Continental Divide. “Mobile homes make up 30 to 40 percent of the housing stock in some counties in the deep South,” Ashley said. “By far, mobile homes are the most vulnerable structures in a tornadic situation.”
  • Nighttime tornadoes. The southeast United States has a higher likelihood of killer nighttime tornadoes. Most states within this region have greater percentages of tornado fatalities occurring at night than other states.“I just completed another study that shows tornadoes from the midnight to sunrise period are 2.5 times as likely to kill as daytime events,” Ashley said. Further, nocturnal tornadoes are more difficult to spot, and people are more likely to be asleep when warnings are issued.
  • Forested areas. Whereas regions within the Great Plains by definition are lacking in tree cover, the mid-South region is more forested, leading to reduced visibility both for the public and spotters.
  • Early season storms. Storms that occur before the national peak in the severe storm season, which spans May and June, may catch people off guard during a tornado event.
  • Complacency. In contrast to other parts of the country, the South lacks a focused “tornado season,” which can lead to complacency. “In the South, people think tornado alley is where you get tornadoes,” Ashley said. “That sort of perception also leads to complacency, which in turn leads to higher fatality rates.” He points out that Oklahoma is known worldwide for the frequency of its tornadoes. Yet the state has fewer fatalities than Arkansas, Alabama and Mississippi.
The media and the National Weather Service must intensify efforts to save lives.  I don't want to underestimate the current efforts because I know many work hard and long hours to communicate life saving information.  New ideas and initiatives must be explored to change this unfortunate fact of life in the mid south. 


Jason H said...

Todd I really wish there was a way that ALL tornado sirens would only go off if the NWS or the local news station for that matter has issued a tornado warning. We have way to many false alarm in my city and I know alot of other cities that people really dont take warnings as serious as they should. I also wish that local law enforcement officers would have to take some classes on the weather so they would know a little more about what they are looking at.

Kinda interesting to see the fatality is highest in the poorest part of the country "the delta region".

Greg Reddin said...

I think we need to reduce our reliance on sirens. The sirens are only meant to warn people of severe weather situations who are outdoors. It's our responsibility to be more aware of conditions via observation, media outlets, info from NWS, wx radio, etc. We should be connected to multiple channels of info and we should take that info seriously. Severe weather complacency is a big problem across the south and midwest. Just look at what happened in Indy. It's such a shame that resulted in injury and especially loss of life.

Omarr Wilson said...

Todd I just had the Time to Actually sit Dow and look at The Weather Blog. That Is absolutly True. That's why when any kind of Severe Weather Threatens any part of The State I do My best Work trying to Get people aware of The Atmosphere and What it Doing. Some people Think it's crazy When all you See the Weather and Omarr Wilson on You timeline on Twitter. But there is a Sturtegic Reason why We do that. We must have more Public Awareness. Then as You said We MUST Work Harder to Sound Sirens and Get Warnings out Better to Save Lives.!

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