Dec. 10-11 Severe Weather

[DanLarsen34]

 

[IWXwx]

Good ol' Tornado Tony

[Calderon]

Paducah tweeted out another survey crew will go back to the Central City, KY area, which would be Bremen, tomorrow. 

[CheeselandSkies]

1 hour ago, Calderon said:

Paducah tweeted out another survey crew will go back to the Central City, KY area, which would be Bremen, tomorrow. 

[WeatherMonger]

[forkyfork]

pedantic nerds ruined tornado climatology

[WVU]

On 12/16/2021 at 8:35 PM, Buckeye05 said:

Since it got buried at the bottom of the previous page, I’m gonna say it again. It looks as though many of the questionable ratings we have been seeing are being caused by NWS WFOs outsourcing survey work to people with no meteorological background. That’s insane to me, and people should be aware that it’s happening.

That is 100% wrong. The NWS has never nor does it now outsource surveys to anyone. The NWS does the surveys. They might get opinions and ask for an engineer like Tim Marshall to review the findings but the last word is the NWS. The NWS is the only legal entity that can determine the rating. No one else.

[WVU]

On 12/16/2021 at 8:24 PM, largetornado said:

The bottom sill plate is missing and broken in places. I also saw another post where an anchor bolt was visible in a CMU foundation but survey noted “no connection.” 
 

this survey is bogus. 

Why is it bogus? Have you done official surveys and coordinated with the NWS?

[WVU]

On 12/22/2021 at 2:12 PM, forkyfork said:

pedantic nerds ruined tornado climatology

Who are the pedantic nerds? 

[WVU]

On 12/16/2021 at 11:47 PM, CheeselandSkies said:

While the Mayfield etc tornado may not have (at least officially, to the best of our limited knowledge of the exact nature of the 1925 event) dethroned the Tri-State Tornado for longest track ever; it did dethrone the April 24, 2010 Louisiana-Mississippi tornado (149.25 miles, another tornado that was almost certainly substantially more intense than its official 170 MPH low-end EF4, but in that case there's not much controversy regarding the rating of the actual damage observed, it just didn't hit much outside of clipping Yazoo City) as the longest-tracked tornado in the NEXRAD era.

This might be the answer you are looking for...The biggest single issue/question for us focused on Obion County, TN...was there a break in the path, or was it in fact a single continuous track that would have broken the record?  Alas, as of now it appears enough of a break to go with separate tracks.

[andyhb]

4 minutes ago, WVU said:

That is 100% wrong. The NWS has never nor does it now outsource surveys to anyone. The NWS does the surveys. They might get opinions and ask for an engineer like Tim Marshall to review the findings but the last word is the NWS. The NWS is the only legal entity that can determine the rating. No one else.

Well regardless of the validity of his statement, I'd like to know why there are so many missing DIs from tornadoes like Mayfield and Vilonia then, especially when others like Moore 2013, Bassfield, and the like are handled much differently. I'd also like to know why there is so much inconsistency for how both conventional and non-conventional DIs are applied.

[WVU]

On 12/17/2021 at 12:33 AM, Buckeye05 said:

The only one that was entirely based on ground scouring was the Philadelphia, MS EF5. It dug deep trenches into the ground, which was assumed to have been indicative of 200+ MPH winds back in 2011. Unfortunately, there isn't a "ground scouring" DI, and since NWS many survey teams are much less open to factoring in non-established DIs and contextual evidence in this day and age, such a thing is not going to be a clincher for an EF5 rating anymore. In fact, it might not be factored in at all. Also, yes, the recent Kentucky tornado did produce the same kind of scouring.

Two main reasons it wasn’t EF-5 imo: fast moving tornado struck a building with high winds that lasted only seconds, an poor building practices limited the number of high end DIs.

[WVU]

On 12/17/2021 at 1:06 AM, brianc33710 said:

Yeah Hackelburg-Phil Campbell EF5 was almost 130 mi & maxed 1.25 mi wide. 

I might of answered this earlier if so I apologize. 

The biggest single issue/question for us focused on Obion County, TN...was there a break in the path, or was it in fact a single continuous track that would have broken the record?  Alas, as of now it appears enough of a break to go with separate tracks.

[WVU]

On 12/15/2021 at 7:56 PM, CryHavoc said:

Don't forget, even if it does this, the assessors will look at building construction and manage to find fault with it.  "There was a dent in the wall from 2016 which caused a structural weakness and therefore cannot be considered worthy of an EF5 rating."

This was an EF5.  Period.  Maxed out violent wedge, long-tracked tornado accounting for numerous records including G2G, a TBSS on radar, lofted debris to 35k feet, foundations swept clean, scouring, vehicles tossed massive distances, trains thrown from their tracks.

So measurements of actual wind speeds doesn't matter (el reno 2013), radar measurements doesn't matter, buildings leveled/decimated doesn't matter, foundations swept clean doesn't matter, incredible instances of one-off damage doesn't matter...

Where is the science, here?  At what point does the EF scale become entirely useless?  It's not consistent, it's not uniform, it's not predictable, and it's changing year-on-year to be more temperamental and stringent.

We may see 1-2 EF5s in a 50 year period if this is the new standard.  The Fujita Scale is one of the few things I know in all of science that favors human-eyed-interpretations of an event over ACTUAL scientific data and measurements.

There's very little science left to it.

The EF scale was developed by a team of meteorologists and wind engineers.

[andyhb]

2 minutes ago, WVU said:

Two main reasons it wasn’t EF-5 imo: fast moving tornado struck a building with high winds that lasted only seconds, an poor building practices limited the number of high end DIs.

That first point is nonsense.

And I also don't see how the second conclusion can be drawn with large holes with no survey results along the path, blanket ratings of several spots that seem to discount the highest end damage in certain locations, and various instances of poor photography of the actual damage sites.

[WVU]

On 12/15/2021 at 7:56 PM, CryHavoc said:

Don't forget, even if it does this, the assessors will look at building construction and manage to find fault with it.  "There was a dent in the wall from 2016 which caused a structural weakness and therefore cannot be considered worthy of an EF5 rating."

This was an EF5.  Period.  Maxed out violent wedge, long-tracked tornado accounting for numerous records including G2G, a TBSS on radar, lofted debris to 35k feet, foundations swept clean, scouring, vehicles tossed massive distances, trains thrown from their tracks.

So measurements of actual wind speeds doesn't matter (el reno 2013), radar measurements doesn't matter, buildings leveled/decimated doesn't matter, foundations swept clean doesn't matter, incredible instances of one-off damage doesn't matter...

Where is the science, here?  At what point does the EF scale become entirely useless?  It's not consistent, it's not uniform, it's not predictable, and it's changing year-on-year to be more temperamental and stringent.

We may see 1-2 EF5s in a 50 year period if this is the new standard.  The Fujita Scale is one of the few things I know in all of science that favors human-eyed-interpretations of an event over ACTUAL scientific data and measurements.

There's very little science left to it.

The EF scale does not change each year. It's been the same since 2007.

Here is an article from Yale...https://yaleclimateconnections.org/2021/05/its-been-a-record-long-time-since-the-last-ef5-tornado-what-does-that-mean/

[WVU]

1 minute ago, andyhb said:

That first point is nonsense.

And I also don't see how the second conclusion can be drawn with large holes with no survey results along the path, blanket ratings of several spots that seem to discount the highest end damage in certain locations, and various instances of poor photography of the actual damage sites.

What makes you think it is nonsense? Do you have experience surveying tornadoes? You weren't part of the survey team. 

[CheeselandSkies]

[Chicago Storm]

The EF scale was developed by a team of meteorologists and wind engineers.

That’s obviously true.

However, when all reliable and known pieces of information are not used in determining the strength/rating of a given tornado (such as radar data from a DOW parked next to a tornado), the rating scale loses merit.

Edit: And to add… Given surveys that are conducted are inconsistent throughout offices across the country, overall ratings (to a degree) and especially statistical tornado counts are worthless these days.

[hlcater]

[andyhb]

24 minutes ago, WVU said:

What makes you think it is nonsense? Do you have experience surveying tornadoes? You weren't part of the survey team. 

Because a tornado's max winds are rated based on the max 3 second gust, and unless this tornado was moving >100 mph (which it wasn't), its size would expose at least certain structures to high winds (including the UK Grain Center) for a longer period than that.

Edit: maybe to say that point was nonsense was too harsh, because I do understand the angle (contrasting with something like the Jarrell tornado), but I think given that there have been a number of other fast-moving EF5 tornadoes and this one did produce a lot of higher end damage, it seems there was enough exposure for total destruction in many instances.

[andyhb]

14 minutes ago, WVU said:

The EF scale does not change each year. It's been the same since 2007.

Here is an article from Yale...https://yaleclimateconnections.org/2021/05/its-been-a-record-long-time-since-the-last-ef5-tornado-what-does-that-mean/

Of course the scale has not changed, but how it's applied does over time and depending on location.

[WVU]

3 hours ago, andyhb said:

Because a tornado's max winds are rated based on the max 3 second gust, and unless this tornado was moving >100 mph (which it wasn't), its size would expose at least certain structures to high winds (including the UK Grain Center) for a longer period than that.

Edit: maybe to say that point was nonsense was too harsh, because I do understand the angle (contrasting with something like the Jarrell tornado), but I think given that there have been a number of other fast-moving EF5 tornadoes and this one did produce a lot of higher end damage, it seems there was enough exposure for total destruction in many instances.

Here is the reason why it was not an EF5..."Two main reasons it wasn’t EF-5 imo: fast moving tornado struck a building with high winds that lasted only seconds, an poor building practices limited the number of high end DIs." I asked the question why it wasn't an EF5 and the reviewer (asked by the NWS to review the findings...and he has almost four decades of experience)  of the storm survey told me why.

 

[WVU]

3 hours ago, andyhb said:

Well regardless of the validity of his statement, I'd like to know why there are so many missing DIs from tornadoes like Mayfield and Vilonia then, especially when others like Moore 2013, Bassfield, and the like are handled much differently. I'd also like to know why there is so much inconsistency for how both conventional and non-conventional DIs are applied.

This survey wasn't handled any differently. The NWS office did the survey (as required) and an engineer (with nearly four decades of experience) was asked by the NWS office to review the findings. I asked him and this is what he said..."Two main reasons it wasn’t EF-5 imo: fast moving tornado struck a building with high winds that lasted only seconds, an poor building practices limited the number of high end DIs." He has more experience doing this than anyone I know and is frequently asked for his opinion.

[WVU]

3 hours ago, andyhb said:

That first point is nonsense.

And I also don't see how the second conclusion can be drawn with large holes with no survey results along the path, blanket ratings of several spots that seem to discount the highest end damage in certain locations, and various instances of poor photography of the actual damage sites.

That wasn't the case nor is it nonsense. The NWS office did the survey as required. The NWS office contacted an engineer/meteorologist with nearly four decades of experience to review the survey. I asked him why it wasn't an EF5 and that was what he told me. You're an meteorologist based on your profile. However I doubt you have done much in the way of tornado surveying.  This person is an expert in this field having done it for so long. The NWS has the final say of the rating by law. 

[WVU]

3 hours ago, andyhb said:

Of course the scale has not changed, but how it's applied does over time and depending on location.

How it's applied is the same regardless where you are (or when). The DAT was updated around 2020 but has been used almost since 2010. Every office has to use the DAT which does take most of the subjectivity away from the ratings.

[MidwestChaser]

5 minutes ago, WVU said:

That wasn't the case nor is it nonsense. The NWS office did the survey as required. The NWS office contacted an engineer/meteorologist with nearly four decades of experience to review the survey. I asked him why it wasn't an EF5 and that was what he told me. You're an meteorologist based on your profile. However I doubt you have done much in the way of tornado surveying.  This person is an expert in this field having done it for so long. The NWS has the final say of the rating by law. 

[WVU]

3 hours ago, Chicago Storm said:

That’s obviously true.

However, when all reliable and known pieces of information are not used in determining the strength/rating of a given tornado (such as radar data from a DOW parked next to a tornado), the rating scale loses merit.

Edit: And to add… Given surveys that are conducted are inconsistent throughout offices across the country, overall ratings (to a degree) and especially statistical tornado counts are worthless these days.

Most of the subjectivity is taken out of surveys using the DAT. I can't say all the subjectivity but as much as possible. Every office has to use the DAT (okay...maybe not Monterey, CA where they gat one tornado every five years. But even they are required). All offices and WCM's have been trained the same. If there is a question an expert is asked to review the survey. I really have not seen any inconsistencies.

[WVU]

3 minutes ago, MidwestChaser said:

Have any extra popcorn? You might need it!

[andyhb]

11 minutes ago, WVU said:

That wasn't the case nor is it nonsense. The NWS office did the survey as required. The NWS office contacted an engineer/meteorologist with nearly four decades of experience to review the survey. I asked him why it wasn't an EF5 and that was what he told me. You're an meteorologist based on your profile. However I doubt you have done much in the way of tornado surveying.  This person is an expert in this field having done it for so long. The NWS has the final say of the rating by law. 

More like I don't just blindly believe what people tell me without doing my own research first.

Tim Marshall only visited a couple of locations (Mayfield and Dawson Springs) along the path in the first place.