Tornadoes that should have been rated F5/EF5

[rdale]

Well, let's not go that far. There is a BIG difference between EF0 and EF5. Those who research tornadoes and develop new warning methodology to keep people alerted care. Does 4 versus 5 matter? No. But 0 to 5? Yep. Bigtime.

 

[Tim Marquis]

Jeff,

Although I agree that I dont see what this post accomplishes. Its like any number of penalties that should or should not have been called in a football game, you can't retroactively go back and decide. I will say I disagree with the following "...some controversy lately with the policy of incorporating mobile radar observations into EF-scale ratings, but to my knowledge, the database of tornado ratings has been rather consistent over time." The rating system hasn't been consistent over time. In fact its probably one of the least consistent data sets we have. Take for example the Kellerville, TX tornado on June 8, 1995. Did you know that V1 found a house that not only was swept clean but 1/2 the foundation was lifted by the tornado? The house was "likely missed by the NWS survey team." Hence the tornado got rated an EF4 vs an EF5. You tell me, if a tornado can physically lift 1/2 a concrete slab and later lift pavement off a Farm to market road if that constitutes a 10 on the DI scale.

I think the work to incorporate more modern technology to estimate ground level wind speed should be included when the data sets are available to complement the traditional rating scale. We shouldn't view having observations as a detriment to the rating network for the sake of consistency (ie Rosell May 18,2013 being EF4 vs EF2, El reno May 31,2013 being rated EF5 vs EF3 due to mobile radar data). That's like saying I'll stick with a Apple I for my working computer to stay consistent with my work.

 

[Andy Berrington]

The Mayflower tornado was not given an EF-5 rating because it was found out the house that was reduced to a concrete slab was not secured with nuts and washers. Plus the cars close to the house where not moved and thus it was given a lesser intensity rating.

There were numerous structures in Vilonia that were missing from the DAT survey (at least looking at the overhead shots along the track). In addition, there was a home that was properly anchored there that was completely swept away, but they chose not to upgrade due to tertiary evidence, which was questionable at best (and they seemed to go to some length to avoid the EF5 rating). I've had this discussion several times in different places and the conclusion reached by the majority every time was there is a lot of inconsistency between different NWS offices and how the EF-scale is used (and that Vilonia was indeed an EF5). Some digging was also done and found that the person "in charge" of rating the tornado (J. Robinson) had a rather unrealistic view of how 1/2 family residences should be treated in the highest DI level.

For the record, aside from the radar windspeeds (which is a whole different issue), the only tornadoes that have been listed here that probably could/should/etc. have been F/EF5 are Vilonia, Kellerville and the 5/24/11 ones. Adding on to Jeff's final sentence there, we can probably say that most of these tornadoes listed were at EF5 strength at some point, but that's an entirely different thing than having the damage/evidence left behind to prove it.

 

[Pete Kustra]

Is this thread based on the desire to have measured winds be a part of the rating process? If so, I was unaware that many tornadoes had been sampled. Or, is this just disagreement with the assessment of the professionals who are the world's leading experts at rating tornado damage?

I'm not just taking any violent tornado and saying "it should have been (E)F5. Every tornado I've listed was based either on it containing 200+ mph winds, or based on its rating being disputed by at least a few experts. I'm not asking for a revision of the EF scale or a re-rating of any of the tornadoes so much as I'm listing tornadoes which were likely of F5/EF5 intensity at some point but never confirmed or given an official rating.

 

[Dan Robinson]

I know we have a separate thread on El Reno, but from what I understood, the consensus within the science/research community was virtually unanimous on EF-5, with principal figures like Bluestein and Doswell asserting there was "no question" it was EF-5. (See their Chasercon talks for those quotes) Has this opinion changed within the research community?

 

[Andy Wehrle]

IMHO, Vilonia/Mayflower '14 was the most blatantly underrated violent tornado of the EF-scale era. As Andy B. notes, they used "tertiary" evidence to justify rating textbook EF5 damage below EF5.

Tuscaloosa '11 was very borderline, and a good case could be made for either rating. Personally I'd have probably gone with EF5 just in deference to the fact that the tornado did high-end EF4 damage in both metro areas it impacted, and appeared to intensify based on radar while in the rural areas in between. Then again, that's why I'm not a meteorologist nor a wind engineer.

I've heard a good case made that if there should have been a fifth EF5 on 4/27/11, it should have been the Ringgold, GA storm which would have made it the first and only E/F5 in Georgia history.

 

[Andy Berrington]

I've heard a good case made that if there should have been a fifth EF5 on 4/27/11, it should have been the Ringgold, GA storm which would have made it the first and only E/F5 in Georgia history.

A lot of the upgrade talk for that tornado was based on this photo of the Cherokee Valley Rd area...



It was found that most of the homes in this area were not properly anchored, so EF5 was not given, although this is still obviously extreme damage. FFC does tend to be a conservative office in general, there was a tornado in Polk/Floyd Counties on 3/15/08 that was looked to be a strong candidate for EF4, but was rated EF3.

 

[Pete Kustra]

It's the lack of consistency between research centers that causes this problem. What one center calls a high-end EF3, another calls a low-end EF4. Whether to go with liberal or conservative damage ratings is a debate best left to the experts.

 

[rdale]

Research centers don't do damage surveying - that's done by local NWS offices.

 

[Pete Kustra]

Research centers don't do damage surveying - that's done by local NWS offices.

My mistake, sorry. I meant NWS offices.

 

[Pete Kustra]

There is a big EF-scale rewrite effort in place now - one of the suggestions was to add more info into the database so radar-based winds, non-normal damage, etc. can be listed.

I've heard this too, though they seem to be taking their time with it - people have been talking about the rewrite effort since 2013, it seems. I guess it isn't exactly top priority, but it definitely would be more consistent and scientific to allow recorded wind speeds to factor into the rating.

 

[rdale]

The meetings were held just a few weeks ago. It's really on this time

 

[Pete Kustra]

I'd like to add the Chickasha-Blanchard tornado of May 25, 2011 to this list based on the fact that trees in its path were literally reduced to stumps, and on the severe ground scouring.

 

[Andy Berrington]

I'd like to add the Chickasha-Blanchard tornado of May 25, 2011 to this list based on the fact that trees in its path were literally reduced to stumps, and on the severe ground scouring.

That was on 5/24/11.

 

[Pete Kustra]

That was on 5/24/11.

Oops, typo. Anyhow, is there a dividing line between what degree of soil scouring constitutes F4/EF4 and F5/EF5 damage? Several tornadoes which have caused deep scouring haven't been rated F5/EF5.