2011-04-27 MISC: AL,TN,MS,KY,OH,IN,WV,GA

[Jeff Duda]

Looking at all of the video, with so much debris, I was wondering if the EF scale can be "skewed" because of what the storm picks up rather than the wind speeds. In other words, when a tornado like the Tuscaloosa one picks up a lot of debris, it wouldn't require as high a wind speed to do a greater amount of damage than the same tornado going through a less industrious area. It would be easier to level a brick house with flying bricks and steel than it would with flying wood given the same speed. Just wondering if that works into the equation when figuring out storm speed and damage.

Be careful saying things like that, Greg. You might just open Pandora's box of endless debate with a statement like that. I think you're getting at one of the deficiencies of the EF-scale, but I'll refer to other threads on this forum for a further discussion.

 

[Ryan McGinnis]

Looking at all of the video, with so much debris, I was wondering if the EF scale can be "skewed" because of what the storm picks up rather than the wind speeds. In other words, when a tornado like the Tuscaloosa one picks up a lot of debris, it wouldn't require as high a wind speed to do a greater amount of damage than the same tornado going through a less industrious area. It would be easier to level a brick house with flying bricks and steel than it would with flying wood given the same speed. Just wondering if that works into the equation when figuring out storm speed and damage.

Since the scale itself is a primarily a damage scale and not a windspeed scale, it couldn't be skewed. EF-0 tornadoes are not all weak, but the scale only measures damage.

The correlating windspeed to each EF category may not be terribly accurate in all situations, but I don't know enough about the topic to make an intelligent comment about it. Hopefully someone familiar with doing damage surveys will jump in.

 

[Kevin Walters]

If the top soil was heavily saturated it might have something to do with how easily the area was gouged. In July 1993 we had a severe storm with 90mph winds. The winds actually peeled back areas of sod next to some of our landscaping. The soil was very wet and once the sod let go it just rolled back several inches deep.

 

[Todd Webb]

When all the reports are finally finished at some point in the future, I'll be very curious to read the conclusions as to why the number of fatalities are apparently higher than the Super Outbreak, given all the technological advances in weather forecasting, communications, etc. since that event.

 

[Zack Hargrove]

Well, for one, these storms hit much more densely populated areas... Tuscaloosa, Birmingham, Huntsville, Chattanooga...

 

[Andy Jackson]

Here's an article I stumbled on:
Washington Post

It is an interesting point of view. I wonder if NWS broadcast towers have power backup? Population density is still a good factor as well, if anyone hasn't seen the "Dallas tornado" scenario they always talk about on the weather channel shows, they mention hundreds of fatalities is a possibility.

 

[Rob Wadsworth]

When all the reports are finally finished at some point in the future, I'll be very curious to read the conclusions as to why the number of fatalities are apparently higher than the Super Outbreak, given all the technological advances in weather forecasting, communications, etc. since that event.

Increased urban sprawl/population density, as well as the particular paths that the tornadoes took.

 

[RWilbanks]

That video from Philadelphia, Miss., is incredible. This is very similar to what happened in Hillsdale and Lenawee Counties in Lower Michigan, on Palm Sunday in 1965. Apparently, the ground in two locations was gouged like this.

 

[Elaine Spencer]

Here's another incredible image:

http://blogs.agu.org/wildwildscienc...atellite-shows-the-darkness-after-the-storms/

It shows a satellite image of nighttime lighting over the mid-South, before and after the tornadoes... much of northern Alabama looks about as dark as North Korea in this image.

 

[Tim Cook]

I've looked all over for closer views of the Tuscaloosa/Birmingham tornado as it approached the Birmingham suburbs. I finally found this, which apparently was shot from an apartment complex in Fultondale, on the very edge of the circulation. I don't think I've seen the link in this thread yet. The most relevant footage begins around 2:00.

http://www.youtube.com/watch?v=ztV9RCZV890

Wow...amazing video. The view outside that guy's place when he looks out at the height of the storm is truly frightening. Thanks for the link.

 

[Mike Smith]

Well, for one, these storms hit much more densely populated areas... Tuscaloosa, Birmingham, Huntsville, Chattanooga...

Louisville, Cincinnati, Xenia, and Huntsville - all hit on April 3, 1974 - are at least as densely populated as the areas hit the 27th. I don't believe population density explains it. My theory is that it was the power failing 12+ hours before the violent tornadoes arrived so that people didn't get the warning on a timely basis and/or were out of their normal routines and could not respond effectively when the warning was received.

Andy's link to the Washington Post will take you to an article about the report I have written. You may email me at msmith ([at]) accuweather DOT com and I'll email it to you if you would like to read the whole thing. I believe the cause of the shocking number of fatalities was the power failures that occurred twelve hours before and still affected well over 500,000 in the tornado-stricken areas when the tornadoes arrived.

Mike

 

[Kevin Walters]

The super outbreak also affected a number of Northern states where almost every house has a basement. Not the case in the Southern states. Not being able to seek underground shelter during a violent tornado is a scary thought.

 

[rdale]

Number of missing & dead is dropping...

http://www.nytimes.com/2011/05/05/us/05missing.html?_r=1&ref=us

 

[Zack Hargrove]

Louisville, Cincinnati, Xenia, and Huntsville - all hit on April 3, 1974 - are at least as densely populated as the areas hit the 27th. I don't believe population density explains it. My theory is that it was the power failing 12+ hours before the violent tornadoes arrived so that people didn't get the warning on a timely basis and/or were out of their normal routines and could not respond effectively when the warning was received.

Andy's link to the Washington Post will take you to an article about the report I have written. You may email me at msmith ([at]) accuweather DOT com and I'll email it to you if you would like to read the whole thing. I believe the cause of the shocking number of fatalities was the power failures that occurred twelve hours before and still affected well over 500,000 in the tornado-stricken areas when the tornadoes arrived.

Mike

I don't completely disagree with you. There were some definite high populations affected by the '74 Outbreak, I just feel like most of the main cities in the '74 Outbreak were more affected in the outskirts and metro areas while the tornadoes such as Tuscaloosa and Birmingham especially hit actual downtown areas. I'm not saying for sure it was more dense this time around, that's just the feeling I get. I do agree with you that a major problem was from the loss of a substantial portion of infrastructure earlier in the day from the squall.

 

[John Farley]

There are likely multiple reasons for the relatively high death toll compared to other events involving violent tornadoes, most of which have been mentioned in this list - lack of basements, power out in many areas, high population density, among other possible factors. Sorting out the relative importance of these various factors will require careful social-scientific research concerning the circumstances under which each person died. That will take a substantial amount of time to complete - the complexity of that task can be seen in the fact that a week later, there is still not a precise death count.

 

[mwenzbauer]

What shocks me is how much higher the death toll is than the Super Tuesday Outbreak of 2008... both were forecast well in advance, but the 2008 outbreak happened more in the dark as the sun sets much earlier at that time of year (as well as the timing catching some people off guard not expecting a early Feb tornado outbreak). On the surface, that would seem to make Super Tuesday possibly more threatening. Super Tuesday didn't appear to have as many strong/violent tornadoes as 4/27 but still had strong tornadoes running through populated areas (like Jackson,TN) and while the 57 deaths were a lot, and people like myself thought it was close to the max number of fatalities a major outbreak could cause with todays excellent warnings, I guess that was not the case.

I think Mike is right that the early storm damage played a major part in breaking down the usual communications... I also think you have to factor that these were some of the strongest tornadoes in a long long time... 15 or more EF4 or stronger, just a crazy number for one day. Obviously we haven't had a day with that many violent tornadoes since 1974 (events like 5/31/85; 4/26/91 and 5/3/99 don't come close to that number). I tend to think it was a once every 40-50 year type event to have that many tornadoes of this strength.

 

[Aaron Kennedy]

I think Mike is right that the early storm damage played a major part in breaking down the usual communications...

To some extent (and probably more so in N AL?)... from the interviews I saw with the Tuscaloosa tornado, I read multiple accounts of injured (or uninjured) victims that said they had warning... but just didn't take it seriously.

 

[Mike Smith]

Birmingham ... hit actual downtown areas.

To correct the record, the tornado wasn't close to downtown BHM. It was in the far west and north suburbs. The 1974 tornado DID hit downtown SDF. While it is too soon to do exact comparisons (the 2011 surveys are not complete), I believe you will find the demographics of 1974 and 2011 to be surprisingly similar in that several population centers were hit and that the population densities were similar (i.e., as opposed to the sparsely populated plains of eastern Colorado).

 

[Mike Smith]

To some extent (and probably more so in N AL?)... from the interviews I saw with the Tuscaloosa tornado, I read multiple accounts of injured (or uninjured) victims that said they had warning... but just didn't take it seriously.

At no point do I say this wasn't a factor. If you read the report, I say it WAS a factor.

So far, two stormtrack members have taken me up on my offer to send the actual report. I'm very comfortable with people disagreeing with me after they have read the report. So, I'm re-offering to send it to anyone that requests it. msmith At accuweather [dot] com

Mike

 

[Glen Turner]

In Tuscaloosa, I know a lot (not all, but a lot) of the deaths occurred in somewhat depressed areas of the city where the construction standards were probably not high.

 

[Clarence Bennett]

While I agree with some of you that the power outages as well as population density played a role in the high death toll, I must raise a concern I have, that people have become desensitized and complacent with the current warning system. We have all of this great new technology that can recognize every little spin up tornado and along with that, we issue tornado warnings on these little spin ups, when I think a severe thunderstorm warning would sometimes suffice.

On top of that, everytime severe weather enters an area, most news outlets are going wall to wall with coverage, televisions are beeping warnings loudly, and emergency managers are sounding tornado sirens all over a county. I can tell you from firsthand experience, that anytime a tornado warning polygon touches any portion of Davidson County, TN, you will hear the sirens blasting in every part of the county that is equipped. I saw this on Easter Sunday, just a couple of weeks ago. There was a birdfart spinup in very far northern Davidson County, while at the same time, I was 30 miles south/southwest and the tornado sirens were going off. Every time this happens, everyone is watching and waiting for their apocalypse to come, which never does. Now if we do this over and over and over, what happens? People laugh and think, "oh, they sound these sirens all the time and nothing ever happens". I have heard it...it has been said to me personally.

This is a huge problem that has to be addressed and I see very little discussion on it. I am not suggesting this was the case on April 27th, but it cannot be ignored.

 

[rdale]

This is a huge problem that has to be addressed and I see very little discussion on it. I am not suggesting this was the case on April 27th, but it cannot be ignored.

I'm not sure anyone is ignoring that. So far all studies show tornado FARs are _not_ a negative for future events. I'm sure this will be looked at more in depth with time, but desensitization is not a lock as of now.

 

[Erik Perozo]

I just want to add my two cents to this whole discussion. I grew up in the heart of Mississippi, roughly 30 miles from one of the EF-5's path. I've spoken with a number of my meteorology friends who as well have grown up in either MS or AL. One of the things that we all agreed on more importantly than the power outages is the fact that people here don't take Tornado warnings as serious. I remember countless times of there being many tornado warnings with absolutely nothing happening and me calling home to tell my grandmother to take shelter only to hear the response that "there isn't going to be a tornado, there never is" and get ignored. As sad as it sounds that's just the way most people think here. I'm not discriminating here so before someone tries and correct me on this I want them to know that I fell within this category growing up. MS and AL have some of the lowest household median incomes so therefore housing is more diverse, meaning there are a lot of non well constructed homes. On top of that there were just to many Long Track Violent Tornadoes that no matter what you lived in the foundation was the only thing left. There are a number of factors involved as to why the death toll was so high and I just wanted to throw in another factor.

@Clarence
I completely agree with the statement that tornado sirens blare no matter what the track is through Davidson Co. I've heard many friends here talk about that. I feel one of the reasons for that happening is the fact there are so many drivers on the road that they try to warn as well and you and I know that no matter what time of day you are on the road it is almost always a traffic mess. Does this make it any better. Not at all. Wished there was a better way.

Does anyone think that there could be a SMS system set in place that can be geo targeted so if there is a reported tornado that people could see where it would track. Wonder if that would open a can of worms.

 

[rdale]

Does anyone think that there could be a SMS system set in place that can be geo targeted so if there is a reported tornado that people could see where it would track.

CMAS will geotarget the warnings to all cell phones based on tower locations, automatically, so that should help.

 

[Aaron Kennedy]

At no point do I say this wasn't a factor. If you read the report, I say it WAS a factor.

Mike, Not disagreeing with you, just chiming in on the possibility that perhaps a higher % of fatalities were due to power as you progress northward throughout AL?