Significant Tornado Events

[Nightking2021]

When it comes to anchoring, it mostly comes down to looking at the edge of the foundation for bolts, straps, nails, or nothing at all. There's some nuance to it but it's not super complex or difficult. Roughly speaking, bolts suggest solid anchoring, nails suggest weak anchoring, and nothing suggests well...a completely unanchored house. The foundation isn't visible in the first photo you posted, so nothing about anchoring can be determined from it. There's other factors too including methods of wall stud connection (straight vs toe-nails), and poured concrete (stronger) vs cinder-block foundations (weaker).

Have a look at the photo WIL9287 posted. Here, the edge of the foundation can be seen. Note how there are no bolts and only some nails sticking out of the sill plate (the plank that is attached to the edge of the foundation). This, combined with that car sitting there undamaged, suggests that this was a poorly anchored house. Does that make sense? In any case, I can DM you with more examples if you want to know more.

Here's an EF-4 rated house from Newnan from the DAT. Note the roof is still largely intact, the trees are not debarked, the car did not move, and there is very poor anchoring. View attachment 8401

Are you talking about this house.? I don't see any evidence of anchoring on this house.

 

[buckeye05]

Are you talking about this house.? I don't see any evidence of anchoring on this house.

Yup. It's barely anchored. A few nails can be seen sticking up near the bumper of the car, but that's it. Nothing else was keeping the walls attached to the sill plates but those few nails. That's very poor anchoring.

 

[zvl5316]

1904 Moscow tornado

 

[Nightking2021]

Yup. It's barely anchored. A few nails can be seen sticking up near the bumper of the car, but that's it. Nothing else was keeping the walls attached to the sill plates but those few nails. That's very poor anchoring.

So Newnan probably should have been rated mid to high-end EF3(150-160 mph).

 

[buckeye05]

View attachment 8402
1904 Moscow tornado

Always been curious about this event. Visually, it seems like it was pretty similar to the 1974 Daisy Hill, IN F5. The few damage photos I can find suggest a pretty intense tornado. The first one below might even have a little bit of wind-rowing going on.

So Newnan probably should have been rated mid to high-end EF3(150-160 mph).

All things considered, probably so.

 

[Nightking2021]

You were talking about proper anchoring and here is a picture from Goldsby, OK on May 24, 2011. It looks like it would probably qualify for a high-end EF4 rating or even EF5 if contextual evidence supports it. That looks more like proper anchoring.

 

[MNTornadoGuy]

You were talking about proper anchoring and here is a picture from Goldsby, OK on May 24, 2011. It looks like it would probably qualify for a high-end EF4 rating or even EF5 if contextual evidence supports it. That looks more like proper anchoring.View attachment 8404

It was given a high-end EF4 rating though it probably was an EF5.

 

[Nightking2021]

It was given a high-end EF4 rating though it probably was an EF5.

Yeah it was given a high-end EF4 rating with winds of 200 mph. It is right on the threshold. It probably did qualify for an EF5 rating based on other contextual factors.

 

[buckeye05]

Yup that Goldsby photo honestly could be used as a textbook example of what good anchoring looks like. Those were both extremely violent, and it’s beating a dead horse at this point, but obviously should have been rated EF5.

One of the craziest things the Chickasha tornado did was severely damage a monolithic concrete dome home, leaving the structure severely cracked, which is incredible.

 

[Nightking2021]

Yup that Goldsby photo honestly could be used as a textbook example of what good anchoring looks like. Those were both extremely violent, and it’s beating a dead horse at this point, but obviously should have been rated EF5.

One of the craziest things the Chickasha tornado did was severely damage a monolithic concrete dome home, leaving the structure severely cracked, which is incredible.

Weren't the Chickasha and Goldsby tornadoes just right behind the El Reno tornado that day in intensity?

 

[WIL9287]

This video is a presentation from Tim Marshall, which was just last week. He said 200 mph is EF-5. He also referred to a monolithic concrete dome home in 2011 that survived but was damaged. And that it had EF-5 damage on either side of it. So it would seem as though he thinks that the Chickasha tornado was an EF-5. We also get a sneak-peak of the new Wood Frame Residence DI on the new EF-Scale in this video!

 

[buckeye05]

This video is a presentation from Tim Marshall, which was just last week. He said 200 mph is EF-5. He also referred to a monolithic concrete dome home in 2011 that survived but was damaged. And that it had EF-5 damage on either side of it. So it would seem as though he thinks that the Chickasha tornado was an EF-5. We also get a sneak-peak of the new Wood Frame Residence DI on the new EF-Scale in this video!

Wow! That is certainly some good news, especially hearing it from Tim Marshall. I wonder if we will see some post analysis rating upgrades? By that definition, Chapman and Rochelle would meet the definition for EF5 too, as they are in the books as 200 MPH EF4s as well. Hopefully the false 2014-till current EF5 drought will be amended.

 

[WIL9287]

Wow! That is certainly some good news, especially hearing it from Tim Marshall. I wonder if we will see some post analysis rating upgrades? By that definition, Chapman and Rochelle would meet the definition for EF5 too, as they are in the books as 200 MPH EF4s as well. Hopefully the false 2014-till current EF5 drought will be amended.

One would hope!

Ah yes, Rochelle, that takes me back to the old days with the original significant tornado events thread!

 

[Nightking2021]

Wow! That is certainly some good news, especially hearing it from Tim Marshall. I wonder if we will see some post analysis rating upgrades? By that definition, Chapman and Rochelle would meet the definition for EF5 too, as they are in the books as 200 MPH EF4s as well. Hopefully the false 2014-till current EF5 drought will be amended.

I think Vilonia 2014 was an EF5 as well.

 

[buckeye05]

I think Vilonia 2014 was an EF5 as well.

Oh without a doubt. It was an absolutely textbook example.

 

[andyhb]

This video is a presentation from Tim Marshall, which was just last week. He said 200 mph is EF-5. He also referred to a monolithic concrete dome home in 2011 that survived but was damaged. And that it had EF-5 damage on either side of it. So it would seem as though he thinks that the Chickasha tornado was an EF-5. We also get a sneak-peak of the new Wood Frame Residence DI on the new EF-Scale in this video!

Where in the video did he say 200 mph was EF5?

 

[Nightking2021]

Oh without a doubt. It was an absolutely textbook example.

If I remember right I think someone on the survey team said even if the house was well-built and swept from the slab that is 200 mph and is still in the EF4 category. Well Tim Marshall says 200 mph is also an EF5.

 

[Juliett Bravo Kilo]

Yup that Goldsby photo honestly could be used as a textbook example of what good anchoring looks like. Those were both extremely violent, and it’s beating a dead horse at this point, but obviously should have been rated EF5.

One of the craziest things the Chickasha tornado did was severely damage a monolithic concrete dome home, leaving the structure severely cracked, which is incredible.

Photos concerning the concrete dome (amazed it took this long to get mentioned in this thread):

This is of another dome that was in the area, but was on the outer edge of Chickasha's circulation, it provides a rough "before and after" view of the dome that was hit.



The dome after it was hit. Keep in mind that the tornado's core just missed it, so it could have been swept away if struck dead on by the tornado:





Interior views of the damage:





Aerial views of the area before and after. Note all the trees nearby uprooted and/or debarked:





Source: https://www.monolithic.org/benefits/benefits-survivability/a-testament-to-the-dome-shape

 

[pohnpei]

This video is a presentation from Tim Marshall, which was just last week. He said 200 mph is EF-5. He also referred to a monolithic concrete dome home in 2011 that survived but was damaged. And that it had EF-5 damage on either side of it. So it would seem as though he thinks that the Chickasha tornado was an EF-5. We also get a sneak-peak of the new Wood Frame Residence DI on the new EF-Scale in this video!

The 2011/5/24 survey report said that they didn't find one single house meet their EF5 criteria in this survey, either El Reno, Chickasha or Goldsby tornado, so they have to look close to contextual damage and unusual DI they can find. From this definition what they claimed, Chickasha have to be rated EF5 beacuse the contextual damage near Meadowlark Lane area was as high as a tornado can reach. All these trees/vehicle damage, concrete dome home damage, scoured asphalt, debris pattern, severe ground scouring confined in this small area add to very high confidence of EF5 intensity in this place. I'm glad to see Tim Marshall can say this. It seems that he already hold this opinion for many years.

 

[WIL9287]

Where in the video did he say 200 mph was EF5?

23:03