Enhanced Fujita Ratings Debate Thread

[WeathermanLeprechaun]

I have seen literally nobody mention the Ashby Nebraska EF2 from earlier this year yet and that is surprising. That thing completely derailed numerous train cars and the locomotive itself of a very long train but it was not included anywhere in the official survey.
I don’t know what the specifics of that one are but it would be very nice if someone could get on that. I don’t have the math skills to figure it out myself.
And figure out if that one would be worthy of an upgrade.
The locomotive itself weighed 220 TONS. 420k pounds. and it was knocked over by that wedge. Someone please get me the wind speeds for that i’d love to see it. I'm watching a youtube video going over it.

That locomotive alone was Around double the weight of the fully loaded grain car’s derailed by the enderlin tornado that were rated EF5.
By all metrics the Ashby Nebraska tornado should also be rated EF5 if this study and this science is to be adhered too.

I'm just gonna say it too the Ashby Nebraska wedge IS an EF5 for me based on this info.
Scratch that, after watching a video I noticed a few things that may poke some holes in this. An electrical box of some kind near by the train looked to be completely undamaged and a few tree’s in the area had less than impressive damage. So, not quite so airtight.
But still extremely impressive and worth doing the calculations for.

Pretty beastly supercell, but i think radar bias wins this thing over for a lot given its extremely impressive VROT several times throughout the tornado's lifetime. I think this tornado peaked probably in the intense (EF3) range but I'm unsure about any higher then that

 

[Ozonelayer]

My thought is probably yes.

Coincidentally, a relevant paper was just put in EOL release by Wakimoto et al. regarding kinematic structures of tornadoes: https://journals.ametsoc.org/view/journals/mwre/aop/MWR-D-24-0176.1/MWR-D-24-0176.1.pdf

At some point you have to admit though that the three dimensional components of a tornado's wind velocity is, well, part of its wind speed at a given point and not just the horizontal wind velocities. The wind speed at a given point is thus √(u^2 + v^2 + w^2) and not just √(u^2 + v^2).

Got it, calculate "√(u^2 + v^2 + w^2)" instead of just horizontal winds. That actually explains why me and Ethan's calculations were so different.

 

[Grand Poo Bah]

here is a list of tornadoes that threw vehicles more then 1 km away (there is quite a lot of events of being thrown 50-999 meters so ima ignore them for now)

before 2007

1. Niles - Hubbard - Wheatland F5 May 1985 | 1+ mile
2. Stratton - McCook F4 June 1990 | 1+ mile
3. Haysville - Andover F5+ April 1991 | 1+ KM
4. Bridge creek - Newcastle - Moore F5+ May 1999 | 1+ mile
5. Loyal Valley F4+ May 1999 | 1+ KM

2007+

1. Wren EF3+ April 2011 | 1.7+ mile
2. El reno - Piedmont - Guthrie EF5 May 2011 | 1+ mile
3. Rochelle EF4+ April 2015 | 1+ mile
4. Cisco EF3 May 2015 | 1+ mile
5. Capitol EF3 June 2018 | 1+ mile
6. Lake City EF3+ April 2025 | 1+ mile

Tornadoes that threw them so far that they were never found OR they were torn in such small parts no one could see it was a vehicle

before 2007

1. Jarrell F5+ May 1997
2. Chaoyang City EFU June 2005

2007+

1. Smithville - Hodges EF5 April 2011 (one was over a mile)
2. Hackleburg - Phil campbell - Athens EF5 April 2011
3. Joplin - Duquesne EF5 May 2011 (there were a lot of 200+ meter ones as well)
4. Henryville EF4+ March 2012
5. Vilonia - Mayflower EF4+ April 2014

Two trucks went missing from Matador as well. One with only the axle found, and the other with only an engine block found.

 

[WeathermanLeprechaun]

Two trucks went missing from Matador as well. One with only the axle found, and the other with only an engine block found.

View attachment 47024
View attachment 47025

Matador is the most contextually stacked violent tornado by far. I'm glad that damage is well documented because this is as clear as it gets for a violent tornado

 

[SilentShadow87]

a other thing to bring up is el reno 2013 , hit quite a lot of oil tanks.

one to bring up is this one.

I've seen that before. Unfortunately, I haven't been able to find any photos of the tanks. But between this and some of the vehicle damage, and considering the wind speed recordings, I've been starting to come back around to the camp that an EF4-EF5 rating might have been justified after all.

 

[tornado examiner]

I've seen that before. Unfortunately, I haven't been able to find any photos of the tanks. But between this and some of the vehicle damage, and considering the wind speed recordings, I've been starting to come back around to the camp that an EF4-EF5 rating might have been justified after all.

IMO It really is all about those compact dense and heavy objects being displaced long distances by sub vorticies. Those don’t rely on any form of hard to standardise variable. Like construction quality. Or the soil factor. Or the composition of a tree.

 

[CheeselandSkies]

Has anyone mentioned the Lincoln-Waverly tornado (precursor to Elkhorn) of April 26, 2024, which also derailed a train? Although to my knowledge it didn't move or loft the cars in the fashion that Enderlin did.

Haven't seen a lot on the Elkhorn tornado itself regarding its potential as an EF5 candidate. Overall I think there were probably several tornadoes in that outbreak that were stronger than their ratings (particularly Minden-Harlan), but nothing egregiously bad about the surveys. They just didn't hit the requisite DIs at peak intensity.

 

[tornado examiner]

Has anyone mentioned the Lincoln-Waverly tornado (precursor to Elkhorn) of April 26, 2024, which also derailed a train? Although to my knowledge it didn't move or loft the cars in the fashion that Enderlin did.

Haven't seen a lot on the Elkhorn tornado itself regarding its potential as an EF5 candidate. Overall I think there were probably several tornadoes in that outbreak that were stronger than their ratings (particularly Minden-Harlan), but nothing egregiously bad about the surveys. They just didn't hit the requisite DIs at peak intensity.

Those were large flat unloaded like, bin cars. Not dense heavy loaded grain hoppers.
There is still a spread of intensities you can get with a tornado derailing a train.
The most impressive feats right now are enderlin and Ashby Nebraska in recent memory too me.

I still would like to see calcs of the wind speeds needed to derail a 220ton locomotive.

 

[Ozonelayer]

I think Lake City needs to be looked at again. This is the Dodge Ram 1500, and it was lofted half a mile by the tornado. Im going to test the formula on is and see what windspeed is required, but I doubt its any lower than Low End EF-4.

 

[tornado examiner]

View attachment 47029

I think Lake City needs to be looked at again. This is the Dodge Ram 1500, and it was lofted half a mile by the tornado. Im going to test the formula on is and see what windspeed is required, but I doubt its any lower than Low End EF-4.

We now have scientific data that we can use to verify higher ratings but the chances are most nws offices are not gonna put in the leg work nws grand forks did and re-evaluations are gonna be….unlikely.
Which is, frustrating.
But I could be wrong. It may start happening and soon

 

[Grand Poo Bah]

Has anyone mentioned the Lincoln-Waverly tornado (precursor to Elkhorn) of April 26, 2024, which also derailed a train? Although to my knowledge it didn't move or loft the cars in the fashion that Enderlin did.

Haven't seen a lot on the Elkhorn tornado itself regarding its potential as an EF5 candidate. Overall I think there were probably several tornadoes in that outbreak that were stronger than their ratings (particularly Minden-Harlan), but nothing egregiously bad about the surveys. They just didn't hit the requisite DIs at peak intensity.

Even the original Fujita scale had boxcars being overturned at F2 and full derailment at F3. Granted the wind speeds were higher than the EF scale, but derailment has never been that impressive or uncommon of a tornado feat.

 

[andyhb]

Got it, calculate "√(u^2 + v^2 + w^2)" instead of just horizontal winds. That actually explains why me and Ethan's calculations were so different.

Not in this case, because the calculation in the paper itself assumes horizontal winds only.

 

[CheeselandSkies]

View attachment 47028
Even the original Fujita scale had boxcars being overturned at F2 and full derailment at F3. Granted the wind speeds were higher than the EF scale, but derailment has never been that impressive or uncommon of a tornado feat.

True. There's that well-known video of the Harvard, IL tornado of January, 2008 derailing a Union Pacific train (as it was in motion) and that tornado's EF2 rating is pretty non-controversial.

 

[tornado examiner]

So, perhaps enderlin’s case really is the outlier among all tornado related derailment throughout history.

But if it really is that easy in most case’s than…i guess they’ll have too make a major distinction between loaded and unloaded car’s if they are too add rail cars as a Di in the revised EF-scale.
As well as the type of car.

 

[andyhb]

True. There's that well-known video of the Harvard, IL tornado of January, 2008 derailing a Union Pacific train (as it was in motion) and that tornado's EF2 rating is pretty non-controversial.

IIRC this equation changes considerably if the train cars are in motion.

 

[SilentShadow87]

It tends to get overshadowed by the Pilger twins, but I'm also pretty confident that the Stanton tornado on 6/16/2014 was the most violent tornado of the day and probably should have been rated EF5. The main Pilger tornado came close, but the grass scouring and vehicle damage weren't quite as extreme.


I also feel like Coleridge could have easily been rated EF4. Even though this house wasn't well anchored, the fact that there was a scoured field and a tossed grain bin nearby heavily suggests a violent tornado imho.

 

[Grand Poo Bah]

So, perhaps enderlin’s case really is the outlier among all tornado related derailment throughout history.

But if it really is that easy in most case’s than…i guess they’ll have too make a major distinction between loaded and unloaded car’s if they are too add rail cars as a Di in the revised EF-scale.
As well as the type of car.

I meant to clarify in my last comment. It's the lofting component that is considered so impressive. Imagine moving a 200 pound dresser. It's way easier to scoot it across the floor yourself than to actually lift it and carry it somewhere. The leverage and strength it requires to do that to a 70,000 pound train car and actually carry it 450 feet is incredible.

 

[tornado examiner]

I meant to clarify in my last comment. It's the lofting component that is considered so impressive. Imagine moving a 200 pound dresser. It's way easier to scoot it across the floor yourself than to actually lift it and carry it somewhere. The leverage and strength it requires to do that to a 70,000 pound train car and actually carry it 450 feet is incredible.

But even in enderlin’s case those loaded grain hoppers that were just tipped over received an EF5 Di.

 

[Ozonelayer]

Not in this case, because the calculation in the paper itself assumes horizontal winds only.

So, just to be clear, calculate vertical and horizontal winds separately?

 

[Grand Poo Bah]

But even in enderlin’s case those loaded grain hoppers that were just tipped over received an EF5 Di.

Oh wow! I didn't realize that. Definitely changes the picture a lot. Was the Nebraska train engine moving when it was tipped?

IIRC this equation changes considerably if the train cars are in motion.

Newton's first law!