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

[Trey Thee]

Greg Forbes just weighed in on the weather channel with his view for the Tuscaloosa wedge (seemed to largely be based on the aerial helicopter survey) that there was EF-5 damage; he said something along the lines that he never had seen before such a wide area of such damage.

One thing that really bothers me, all these guys say they've been doing this for 30 years and never seen anything like it. Yet Greensburg was a mile + wide with devastating destruction...

OKC had higher wind speeds varied in width from .5 to 2 miles and impacted a more significant metro. They seem to have a memory thats about 6 mos long. Not to mention as others have the South gets hit with significant tornadoes ever year, not in this volume, but they have one or two major tor's a year.

These storms were significant and violent and the number of EF3+ tor's appears to be almost unheard of. But any particular tor could easily be compared with other storms over the last 20 years.

 

[Chad Ringley]

High end EF4 E of Chattanooga, TN, a little under a half mile wide, 15 mile track length.

0829 PM TORNADO 4 SE COLLEGEDALE 35.00N 85.00W
04/27/2011 HAMILTON TN NWS EMPLOYEE

EF4. MAX WIND SPEED 190 MPH. PATH WIDTH 800 YARDS. PATH
LENGTH 15 MILES. CONTINUOUS NORTHEAST TRACK LEADING INTO
EASTERN PORTIONS OF CLEVELAND.

 

[E. Clark]

http://www.alabamawx.com/ just posted #2 of the Aerials. #1 is a couple posts below. Good quality.
The drag marks on pavement and grass #1 at the first 20 seconds of tape is amazing. The whole thing is mind boggling. I did see some areas of pavement removed and a lot of de-barking. Maybe not a EF 5 on the entire path- but certainly in areas. Toward the end of #2 is what looks like a water installation with rubber lined ponds. One of the ponds looks sucked dry.

 

[Trey Thee]

http://www.alabamawx.com/ just posted #2 of the Aerials. #1 is a couple posts below. Good quality.
The drag marks on pavement and grass #1 at the first 20 seconds of tape is amazing. The whole thing is mind boggling. I did see some areas of pavement removed and a lot of de-barking. Maybe not a EF 5 on the entire path- but certainly in areas. Toward the end of #2 is what looks like a water installation with rubber lined ponds. One of the ponds looks sucked dry.

Oh man, thanks for the vid, I've been trying to find something this good/detailed all evening. I appreciate the post.

 

[Mike Smith]

OKC had higher wind speeds [than the Greensburg outbreak]

What is your basis for that statement?

Mike

 

[Trey Thee]

What is your basis for that statement?

Mike

Well for one, I've read that Oklahoma storm in 99 had the highest wind speeds ever recorded in a tornado.

Second, why did you edit my post to say something I never said? I said OKC had higher wind speeds, as in higher than whats been reported so far out of Alabama, as well as more significant destruction, ground swirl patterns, trees completely stripped, grass stripped out of the ground etc etc (talking about a single storm not the entire event)...I never said it had a higher wind speed than greensburg, though everything I've read says that is the case.
http://www.usatoday.com/weather/tornado/wtwur318.htm

The point is that these TV personalities seem to have the shortest memories of anyone I'm aware of. So instead of getting legitimate data, they simply say they've never seen anything like it. There have been several substantial F5's I can remember in my lifetime, I've seen the damage from two of them up close and personal. So if some of these guys like Dr Forbes for example have been doing this forever, they should have seen this sort of destruction before, thats my point. But I guess it doesn't get TV ratings to just give us the facts and the information. I dunno...


edit: another thing I've noticed a lot of these completely destroyed homes are not the same type of homes we build here on the plains. Many of the home's I've seen so far that are "wiped" clean if you will, are not slab homes built with anchor bolts. Many of them are built on a crawl and the footing is built out of cinder blocks. Doesn't make it any better for those who lost everything, but when considering the destruction and wind speed, the construction quality must also be considered.

Having said that, much of this Tuscaloosa damage appears to be EF5.

 

[MClarkson]

anyone have a link to that video of the large tornado moving down a hillside?

 

[j_scheerer]

anyone have a link to that video of the large tornado moving down a hillside?

Here ya go.

Watch video >

 

[Michael Riedl]

anyone have a link to that video of the large tornado moving down a hillside?

http://www.youtube.com/watch?v=zEr2lCnQcow&feature=youtu.be

Very Impressive.

 

[B Ozanne]

Previously posted link, but this video shows a train bridge over a ravine that was totally destroyed:

http://www.youtube.com/watch?v=G6giQ3csbUg

 

[MClarkson]

Thats the one! Thanks guys... Makes those hills look pretty small...

 

[Andy Wehrle]

Well for one, I've read that Oklahoma storm in 99 had the highest wind speeds ever recorded in a tornado.

...I never said it had a higher wind speed than greensburg, though everything I've read says that is the case.
http://www.usatoday.com/weather/tornado/wtwur318.htm

Wurman says the 318-mph winds probably were a couple of hundred feet above the ground, not at ground level where the twister was doing the damage that later led the National Weather Service to classify the storm as an F-5.

That's Part A.

Part B is that few people who are not meteorologists or weather enthusiasts understand how the F-scale and the EF-scale are interconnected, and few news reports do a good job of explaining it.

The Greensburg tornado was rated on the EF-scale, so it is always going to be described as having winds in excess of 200 MPH. That doesn't mean it was ~100 MPH weaker than Bridge Creek/Moore '99. In fact, the two storms were likely quite similar in strength. What the EF-scale did was revise the windspeed estimates downward to reflect new knowledge - that it doesn't take ~300 MPH winds to do level 5-type damage, and the windspeed ranges were likely too high at the upper end of the scale.

To use another example, until the EF-scale was implemented, it was widely accepted that a "mere" high-end F3 tornado contained winds close to or exceeding 200 MPH. The Stoughton tornado of 8/18/2005 was such a storm. If the same tornado were to occur today, it would be rated EF3, with a wind speed estimated between 136 and 165 MPH. The tornado did not suddenly get weaker. We just figured out that F3-type damage actually takes place at a lower windspeed than Fujita originally estimated.

 

[Trey Thee]

That's Part A.

Part B is that few people who are not meteorologists or weather enthusiasts understand how the F-scale and the EF-scale are interconnected, and few news reports do a good job of explaining it.

The Greensburg tornado was rated on the EF-scale, so it is always going to be described as having winds in excess of 200 MPH. That doesn't mean it was ~100 MPH weaker than Bridge Creek/Moore '99. In fact, the two storms were likely quite similar in strength. What the EF-scale did was revise the windspeed estimates downward to reflect new knowledge - that it doesn't take ~300 MPH winds to do level 5-type damage, and the windspeed ranges were likely too high at the upper end of the scale.

To use another example, until the EF-scale was implemented, it was widely accepted that a "mere" high-end F3 tornado contained winds close to or exceeding 200 MPH. The Stoughton tornado of 8/18/2005 was such a storm. If the same tornado were to occur today, it would be rated EF3, with a wind speed estimated between 136 and 165 MPH. The tornado did not suddenly get weaker. We just figured out that F3-type damage actually takes place at a lower windspeed than Fujita originally estimated.

yes thats correct...thats the way I understand it as well...but windspeeds were measured with equipment on the may 3 1999 storm...they were not all just estimates...There is quite a lot of weather equipment and data in the OKC area, numerous chasers converged on that storm. I believe Greensburg had estimated wind speeds of 205 to 240mph but i'm not sure there were any measurements taken with any DOW vehicles.


Anyways, that wasn't really my point. My point was these sort of storms happen more often then you'd think listening to people who have supposedly been around the block a time or two. As I stated earlier there's been numerous F5's and EF5's in my lifetime.

Hell nevermind, I've tried to make my point a couple times...

 

[Mike Smith]

Trey, in post #211, you stated, "One thing that really bothers me, all these guys say they've been doing this for 30 years and never seen anything like it. Yet Greensburg was a mile + wide with devastating destruction...

OKC had higher wind speeds varied in width from .5 to 2 miles and impacted a more significant metro."

Perhaps it is not what you intended to say (we all type things ambiguously at times) but you are clearly writing about Greensburg. I don't understand why you are complaining about 'editing' to change your meaning.

FYI: OKC and BHM metros are identical in population with 1.2 million each.

 

[Trey Thee]

Trey, in post #211, you stated, "One thing that really bothers me, all these guys say they've been doing this for 30 years and never seen anything like it. Yet Greensburg was a mile + wide with devastating destruction...

OKC had higher wind speeds varied in width from .5 to 2 miles and impacted a more significant metro."

Perhaps it is not what you intended to say (we all type things ambiguously at times) but you are clearly writing about Greensburg. I don't understand why you are complaining about 'editing' to change your meaning.

FYI: OKC and BHM metros are identical in population with 1.2 million each.

That was all in reference to the Alabama storms. Greensburg was very wide at times rivaling these storms with catastrophic destruction. OKC was similar with actual measured windspeeds that were pretty outrageous and on par or stornger than any single storm in Alabama based on the data we have so far. Yet guys like Forbes, people on Fox and CNN repeatedly say they've never seen this sort of destruction before? Where the hell have they been the last 20 years? There was similar destruction in a 1991 outbreak, 1999, 2003, 2007, etc


Bham is similar size thats true. With similar destruction, so if anyone has been paying attention the last 10 or 20 years this has been seen before.

edit: I am typing between commercials and drinking beer, so its possible I'm being a bit ambiguous, I apologize. My entire point is that this stuff happens, its happened before, it'll happen again, sensationalizing it doesn't do any good. Providing facts, data etc does tremendous good, as opposed to "we've never seen anything like this" when it happens pretty frequently unfortunately. What doesn't happen as frequently is the NUMBER of EF3, EF4 and potentially EF5 storms in a single day.