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Enhanced Fujita Ratings Debate Thread

locomusic01

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Will repost this because it came up on another forum. Just so much crap.
King Of The Hill Reaction GIF by MOODMAN
 

TH2002

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400mg sodium? Not nearly salty enough.
On the bright side, most people are gonna eat two or three WeatherWeenies™ per serving. Also, our horses would love them too much if there was too much sodium.

Weenie Hut Junior or Weenie Hut General?
Not sure, but hopefully John Robinson would be happy to take up residence at either one. Gotta love how he plays stupid when he mentions "some on the [EF scale] committee felt that a house should never be rated EF5" - namely, him.
 

locomusic01

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The bit about it having 200 mph windspeeds is also something that happened with Chapman, as it has 200mph wind speeds listed in the NOAA database. Not EF5, just high-end EF4 lol.
Yeah, it's especially silly because if you use his reasoning re: expected wind speeds, I believe (didn't check so feel free to correct me) the only DIs that have expected values in the EF5 range for the highest DOD are mid/high-rises and institutional buildings. So effectively the only way you'll ever get an EF5 in his world is if a tornado absolutely destroys a large office building or hospital or prison or something.

One might be inclined to wonder what, exactly, the purpose is of even having a rating that's almost designed never to be used.
 

ColdFront

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Yeah, it's especially silly because if you use his reasoning re: expected wind speeds, I believe (didn't check so feel free to correct me) the only DIs that have expected values in the EF5 range for the highest DOD are mid/high-rises and institutional buildings. So effectively the only way you'll ever get an EF5 in his world is if a tornado absolutely destroys a large office building or hospital or prison or something.

One might be inclined to wonder what, exactly, the purpose is of even having a rating that's almost designed never to be used.
I’m almost positive the ASCE would nitpick and find something about those buildings that would negate the rating given as an ef5 in the event it happened. See their mind blowing commentary on Joplin and Jarrell.

I know the ASCE has nothing to do with rating tornados or formulating the scale, but those same “engineering mindsets” are a big part of the Enhanced Fujita scale update.

Their commentary on Joplin:
Only 4 percent of the damage could be linked to an EF-4 tornado, which can have winds speeds ranging from 168 to 199 mph. The ASCE investigators found no EF-5 level tornado damage to buildings at all.

I ask at this point, why even have a 5?
 
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andyhb

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Ricky from NWS Chicago has an opinion on that, boom.

To the supposed lack of EF-5s since Moore, if EF-5 were adjusted down to 190+ mph, we'd have seen the "normal" amount of EF-5s over the past 10 years. Particularly with that DI and DOD for houses.

As an NWS employee, I think that the agency as a whole has lost the plot when it comes to damage ratings. Having some reference to engineering standards is all well and good, but an impossible standard to reach EF-5 has been set based off building codes that don't exist in much of the country.

We've become fixated on finding everything a tornado didn't do as opposed to judging what a tornado did do with respect to totality of damage. If a large swath of a town has catastrophic destruction, it's not the town's fault if they don't have structures built to withstand >200 mph winds. The lower bound on the DIs is used too liberally imo.

Vilonia is an example less than a year after Moore of a tornado that by all accounts should have been rated EF-5. Prior to that, there's a good case to be made that Tuscaloosa 2011 should have been EF-5. On the flipside of that, it seems likely that the post-Moore survey standards would have yielded at least a few less EF-5s on April 27, 2011.

In recent years, I think Mayflower is probably the best example of how the pendulum has swung well too far in the direction of assigning impossible engineering standards to reach EF-5.

Hopefully, the forthcoming updates to the EF scale help bring things back to a more reasonable/realistic place.
 

andyhb

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Yeah, it's especially silly because if you use his reasoning re: expected wind speeds, I believe (didn't check so feel free to correct me) the only DIs that have expected values in the EF5 range for the highest DOD are mid/high-rises and institutional buildings. So effectively the only way you'll ever get an EF5 in his world is if a tornado absolutely destroys a large office building or hospital or prison or something.

One might be inclined to wonder what, exactly, the purpose is of even having a rating that's almost designed never to be used.
Shopping malls (EXP bound DOD 9 for this is 204 mph) would also be EF5, but good luck getting that rating. That's still centralized to cities.
 

andyhb

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"We've become fixated on finding everything a tornado didn't do as opposed to judging what a tornado did do with respect to totality of damage."

This quote from Ricky particularly hits the nail on the head @buckeye05.
 

andyhb

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He's dropping more goods in this thread: https://www.americanwx.com/bb/topic/59087-mayflower-vilonia-tornado-of-2014/

I feel confident in saying that Rochelle-Fairdale on April 9, 2015 was also an EF-5. The wind rowing in the aerial photo from IEMA Air-One looks strikingly similar to that seen in some of the April 27th tornadoes. The survey process for that tornado was rushed imo - we never had an in person QRT consultation, just a virtual one. I'm not sure how that was decided upon, if the QRT felt comfortable going virtual or our since retired MIC pushed for a faster decision to stick with high end EF-4.
One of the turning points in how the pendulum has swung toward too stringent an EF-5 standard was the engineering assessment in the wake of the Joplin tornado. I I'm not mistaken, that assessment found that hardly any/none of the destroyed homes would have withstood EF-3 winds. It seems like, despite Moore receiving an EF-5 designation, that since that Joplin engineering assessment, there's been a granular focus on home construction vs. coverage of damage DI 10 with the highest DOD.
 

A Guy

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Will repost this because it came up on another forum. Just so much crap.
The second paragraph is, in my opinion, one of the main sticking points, because as I have explained before the implicit intent of the Fujita scale was to rate primarily by using a very common structure. Robinson is obviously not going to admit if he was 'the person', and that fact it got through rather than being contested is a sign of implicit agreement from the others. I wouldn't be surprised if it was someone else like Marshall though. Either way the solution is very simple, which is to move the threshold to 200 mph - which is what it should have been according to the original explanation of the equivalency between the F and EF scales.

There is an obvious bankruptcy in the idea that a house has to be of somehow 'superior' construction to get EF5 when apparently the standard of construction to achieve the 'expected' value is extremely rare. As a matter of fact it obvious to anyone in the real world that a house which has 'full load path' with straps and hurricane clips etc. is of superior construction.

The main problem here is not anything to do with the science or engineering, it is the groupthink that exists amongst the people who actually have the power over these things. This is a pretty normal thing in power hierarchies really, but it comes with the important implication that change has to come from within that system. That change might only come when the current lot retire (or die) and if they are replaced by people who think differently.
 

Bender

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Will repost this because it came up on another forum. Just so much crap.
The second paragraph is, in my opinion, one of the main sticking points, because as I have explained before the implicit intent of the Fujita scale was to rate primarily by using a very common structure. Robinson is obviously not going to admit if he was 'the person', and that fact it got through rather than being contested is a sign of implicit agreement from the others. I wouldn't be surprised if it was someone else like Marshall though. Either way the solution is very simple, which is to move the threshold to 200 mph.

There is an obvious bankruptcy in the idea that a house has to be of somehow 'superior' construction to get EF5 when apparently the standard of construction to achieve the 'expected' value is extremely rare. As a matter of fact it obvious to anyone in the real world that a house which has 'full load path' with straps and hurricane clips etc. is of superior construction.

The main problem here is not anything to do with the science or engineering, it is the groupthink that exists amongst the people who actually have the power over these things. This is a pretty normal thing in power hierarchies really, but it comes with the important implication that change has to come from within that system. That change might only come when the current lot retire (or die) and if they are replaced by people who think differently.
It's certainly a complex issue. As an outsider, I find it amusing that we're talking about the EF scale when we have the Bender scale, which is obviously superior. But in all seriousness, there are likely a number of factors that go into the decision-making process for rating tornadoes, not just the quality of construction. The whole system could use some reevaluation and updating, and it's good to see people like Ricky speaking out about it.
 

ColdFront

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The second paragraph is, in my opinion, one of the main sticking points, because as I have explained before the implicit intent of the Fujita scale was to rate primarily by using a very common structure. Robinson is obviously not going to admit if he was 'the person', and that fact it got through rather than being contested is a sign of implicit agreement from the others. I wouldn't be surprised if it was someone else like Marshall though. Either way the solution is very simple, which is to move the threshold to 200 mph - which is what it should have been according to the original explanation of the equivalency between the F and EF scales.

There is an obvious bankruptcy in the idea that a house has to be of somehow 'superior' construction to get EF5 when apparently the standard of construction to achieve the 'expected' value is extremely rare. As a matter of fact it obvious to anyone in the real world that a house which has 'full load path' with straps and hurricane clips etc. is of superior construction.

The main problem here is not anything to do with the science or engineering, it is the groupthink that exists amongst the people who actually have the power over these things. This is a pretty normal thing in power hierarchies really, but it comes with the important implication that change has to come from within that system. That change might only come when the current lot retire (or die) and if they are replaced by people who think differently.
I would absolutely love to hear his thoughts on the current EF5 drought and if anyone on those initial Enhanced Fujita scale committees ever brought up any of the issues that we are seeing take place over the past ten years.

This is straight from the horse’s mouth in the ASCE review of Joplin:

The team found no evidence of building damage from winds at 200 mph or greater, the minimum threshold for an EF-5. The study concluded that EF-5 ratings were nearly impossible to observe given the high construction quality threshold that must be met for determining that level of wind speed.

I actually have zero faith in the updates to the EF scale remedying this problem, especially if they try and make it more “engineering standard” than it already is. Not only that, but factoring in the wind duration of the storm as well could lead to a lot of nitpicking.

Are there any prominent meteorologists, like a Greg Forbes and other than Doswell, that have came out against the entire cluster **** that is the EF scale now? Were those initial steering committees for the EF scale stacked with more engineering focused stakeholders than actual climate and atmospheric scientists? Doswell doesn’t mince words on the folks from Texas Tech in his blog…
 
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andyhb

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I’m almost positive the ASCE would nitpick and find something about those buildings that would negate the rating given as an ef5 in the event it happened. See their mind blowing commentary on Joplin and Jarrell.

I know the ASCE has nothing to do with rating tornados or formulating the scale, but those same “engineering mindsets” are a big part of the Enhanced Fujita scale update.

Their commentary on Joplin:
Only 4 percent of the damage could be linked to an EF-4 tornado, which can have winds speeds ranging from 168 to 199 mph. The ASCE investigators found no EF-5 level tornado damage to buildings at all.

I ask at this point, why even have a 5?
Oh but, EF4 is 166-200 mph...
 

andyhb

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I would absolutely love to hear his thoughts on the current EF5 drought and if anyone on those initial Enhanced Fujita scale committees ever brought up any of the issues that we are seeing take place over the past ten years.

This is straight from the horse’s mouth in the ASCE review of Joplin:

The team found no evidence of building damage from winds at 200 mph or greater, the minimum threshold for an EF-5. The study concluded that EF-5 ratings were nearly impossible to observe given the high construction quality threshold that must be met for determining that level of wind speed.

I actually have zero faith in the updates to the EF scale remedying this problem, especially if they try and make it more “engineering standard” than it already is. Not only that, but factoring in the speed of the storm as well could lead to a lot of nitpicking.

Are there any prominent meteorologists, like a Greg Forbes and other than Doswell, that have came out against the entire cluster **** that is the EF scale now? Were those initial steering committees for the EF scale stacked with more engineering focused stakeholders than actual climate and atmospheric scientists? Doswell doesn’t mince words on the folks from Texas Tech in his blog…
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.
 
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