Enhanced Fujita Ratings Debate Thread

[ColdFront]

Factoring in the speed of the storm would be stupid, because it's literally a part of the tornadic winds. Translational velocity + rotational velocity = the winds from a tornado that impact structures. End of story. It would be duration of said winds that would be in question.

That’s exactly what it was. I mixed up speed vs wind duration trying to recall what was in the presentation posted in this thread. I’ll correct my initial comment.

 

[Wind Driven Coconut]

Really good discussion here. After much of the curiosity about final rating for Rolling Fork I started a little curiosity research about how many EF-5 tornadoes would be added to the list if the threshold for EF-5 was lowered to 190 mph. Seems there would be approximately 7 since 2013: Washington, IL, Vilonia, AR, Rochelle, IL, Chapman, KS, Mayfield, KY, and Rolling Fork (possible Bassfield but I could not find a final windspeed on that one).

I’m sure it’s way too simple of a solution to simply lower the threshold for EF5 attain ability, which is obviously more likely to be achieved in smaller towns simply by looking at the small sample size above, but the flip side is that currently there is a six level scale that exists to determine tornado strength in which apparently the highest level on that scale is unachievable in 98% of all cases. That makes no sense to me either.

 

[CheeselandSkies]

Really good discussion here. After much of the curiosity about final rating for Rolling Fork I started a little curiosity research about how many EF-5 tornadoes would be added to the list if the threshold for EF-5 was lowered to 190 mph. Seems there would be approximately 7 since 2013: Washington, IL, Vilonia, AR, Rochelle, IL, Chapman, KS, Mayfield, KY, and Rolling Fork (possible Bassfield but I could not find a final windspeed on that one).

I’m sure it’s way too simple of a solution to simply lower the threshold for EF5 attain ability, which is obviously more likely to be achieved in smaller towns simply by looking at the small sample size above, but the flip side is that currently there is a six level scale that exists to determine tornado strength in which apparently the highest level on that scale is unachievable in 98% of all cases. That makes no sense to me either.

In practice, seems to be more like 99.998% of all cases.

 

[Wind Driven Coconut]

In practice, seems to be more like 99.998% of all cases.

Admittedly, I was being generous

The EF5 unicorn status should be applied for other rating systems as well:
Cat 6 hurricane - winds above 275 mph
KBB Used Car Rating - add “never owned” to the Condition question
6th star for Amazon ratings for exemplary service - but gray out the option so it can’t be selected.

Yes all of the above are silly, but how is it any different than having a 6th level of intensity for a tornado that can no longer be achieved short of a “lottery odds” hit on the one place in any city where the construction was good enough to make that determination?

Since it does seem much more possible at 190, seems a very easy fix, and the number of tornadoes that would be added in the last 10 years (seven) is pretty much on par with the average prior to this new approach.

 

[wasatch]

I think one of the Pilger tornadoes was rated 190 also... in theory I think you'd also have to bump Tuscaloosa (perhaps some other 4/27 ones?) and one or two of the 5/24/11 OK high EF4's to EF5...

 

[pohnpei]

Really good discussion here. After much of the curiosity about final rating for Rolling Fork I started a little curiosity research about how many EF-5 tornadoes would be added to the list if the threshold for EF-5 was lowered to 190 mph. Seems there would be approximately 7 since 2013: Washington, IL, Vilonia, AR, Rochelle, IL, Chapman, KS, Mayfield, KY, and Rolling Fork (possible Bassfield but I could not find a final windspeed on that one).

I’m sure it’s way too simple of a solution to simply lower the threshold for EF5 attain ability, which is obviously more likely to be achieved in smaller towns simply by looking at the small sample size above, but the flip side is that currently there is a six level scale that exists to determine tornado strength in which apparently the highest level on that scale is unachievable in 98% of all cases. That makes no sense to me either.

The wind speed for Bassfield was 190mph and Pilger 2014 was 191mph. Chapman was 200mph in ncdc but still 180mph in nws website.

 

[pohnpei]

https://www.essl.org/cms/wp-content/uploads/20230506_IF-scale_v0.99.9d.pdf

I'm deeply glad they used 3D instantaneous winds as the definition rather than 3s 10m horizontal winds defined by EF scale. That's the right way.

 

[andyhb]

Today is the day we get endlessly reminded that it’s been 10 years since an EF5 whilst fully knowing that that’s simply not true.

 

[andyhb]

Well this article ought to stir the hornets' nest a bit.

Marshall saying "there's no difference between a high end EF4 and an EF5" is pretty hmmm-worthy when it's obvious that public perception of an event is changed pretty dramatically following a 5.

 

[Tanner]

Well this article ought to stir the hornets' nest a bit.

Marshall saying "there's no difference between a high end EF4 and an EF5" is pretty hmmm-worthy when it's obvious that public perception of an event is changed pretty dramatically following a 5.

Yeah, I mean the title says it all. We have "changed the way we rate tornadoes" to become more stringent when going above EF4, for whatever reason. It isn't because the philosophy of rating tornadoes has changed, it's the execution and reasoning that has changed. Of course, this relates solely to the fact that after Moore, this apparent shift started to rear its ugly head.

That being said, I like to check in. What tornadoes specifically from the 2010's/20's garner an EF5 rating pre-2013? The blind obvious being Vilonia for most of the census here.

 

[jiharris0220]

Well, to mark down the obvious ones, imo.
Goldspy, Chickasaw, (surprise surprise) Vilonia, Rochelle, and Bremen.

These aren’t exactly what I would consider ef5s, but have no doubt contained these wind speeds.
New wren, Tuscaloosa, Washington, Bassfield, and Rolling folk.

 

[Shakespeare 2016]

Well, to mark down the obvious ones, imo.
Goldspy, Chickasaw, (surprise surprise) Vilonia, Rochelle, and Bremen.

These aren’t exactly what I would consider ef5s, but have no doubt contained these wind speeds.
New wren, Tuscaloosa, Washington, Bassfield, and Rolling folk.

Add Chapman 2016. to that list.

 

[TH2002]

That being said, I like to check in. What tornadoes specifically from the 2010's/20's garner an EF5 rating pre-2013? The blind obvious being Vilonia for most of the census here.

I still may have missed a few

2011:
New Wren, Tuscaloosa, Ringgold, Cordova*, Ohatchee*, Chickasha, Goldsby, Berlin*

2012:
Henryville*

2013:
Granbury*, Washington*

2014:
Vilonia, Louisville, Stanton, Pilger*, Pilger East*

2015:
Fairdale, Cisco*, Holly Springs

2016:
Chapman

2017:
Perryville*

2018:
Camp Crook

2020:
Bassfield*

2021:
Mayfield*

*denotes tornadoes that are more debatable, or don't have enough information available.

 

[UK_EF4]

Thought this was an interesting snippet from that article, given Tim Marshall also surveyed Vilonia (though from what I am aware he wasn't shown the most intense damage? - someone correct me if I am wrong).

 

[andyhb]

Thought this was an interesting snippet from that article, given Tim Marshall also surveyed Vilonia (though from what I am aware he wasn't shown the most intense damage? - someone correct me if I am wrong).

None of the most intense damage/potential highest end DIs were in his report.

 

[Austin Dawg]

"there's no difference between a high end EF4 and an EF5"

 

[TH2002]

That's Tim Marshall basically admitting that high-end EF4 has become the new EF5, and that tornado ratings are essentially meaningless these days.