Severe Weather Threat 4/25-4/26, 2024 - (Thursday, Friday)

[NorthGaWeather]

So it appears the Elkhorn, NE tornado leveled a pretty large and expensive home near Prospect Hill Cemetery. I can't tell if it's actually slabbed or just separated from its sublfoor though. Here's a potential problem too...judging by Google maps, it's in a private gated community. Will the NWS survey team be able to do a survey on foot?
View attachment 26030

Yes. This is usually coordinated through the EMA or the jurisdiction having authority. As long as it is identified, they can view it. I know in Georgia, ACCG guidance for local ordinances based off OCGA give a lot of latitude to local jurisdictions and EMA directors after a disaster with entering private areas.

 

[tornado examiner]

I’d say that the Blair Nebraska tornado is easily the most powerful the state has had in a very long time…

 

[A Guy]

DOW found winds of ~224 mph in the Harlan IA tornado on Friday.

Kinda disappointed he didn't say what height it was recorded at, or whether that's a 3 sec reading or instantaneous. I read a lot of Wurman's papers last week and he's certainly quite into his theory that tornadoes' strongest windspeeds are in the corner flow region near the ground. Reading between the lines he's itching to get a 10 m agl measurement of a strong-violent tornado. Not surprising either as the research he's doing has the potential to make or break the EF scale.

 

[Tempestas Tonitrua]

Kinda disappointed he didn't say what height it was recorded at, or whether that's a 3 sec reading or instantaneous. I read a lot of Wurman's papers last week and he's certainly quite into his theory that tornadoes' strongest windspeeds are in the corner flow region near the ground. Reading between the lines he's itching to get a 10 m agl measurement of a strong-violent tornado. Not surprising either as the research he's doing has the potential to make or break the EF scale.

Yep. There’s also his paper he published a while back, and I’m paraphrasing, on how most tornados were usually assigned lower ratings by the EF scale when his measurements would actually bump them up a few spots.

 

[A Guy]

Yep. There’s also his paper he published a while back, and I’m paraphrasing, on how most tornados were usually assigned lower ratings by the EF scale when his measurements would actually bump them up a few spots.

He's not the only person with the same thinking. One of Frank Lombardo's recent papers was pointedly titled "An Approach for Assessing Misclassification of Tornado Characteristics Using Damage". That said I'm a bit iffy on his tree fall models without more definitive proof that the Rankine Vortex model is a good enough approximation of real life that the estimates are accurate.

 

[tornado examiner]

An fairly violent EF3 was confirmed near Elba Nebraska…

 

[andyhb]

 

[notsoencrypted]

That thing was just absolutely massive. It actually kind breaks my brain when looking at the photos.

 

[Shakespeare 2016]

That thing was just absolutely massive. It actually kind breaks my brain when looking at the photos.

That is what I would call a monster tornado. The most intense damage I have seen is possibly in the 170 to 190 mph range which would make it an EF4.

 

[Shakespeare 2016]

Ok found it. The first video of the EF4ish looking damage is in the Lariat Lane area. Also my suspicions are confirmed. That third completely obliterated structure I posted a screen cap of was not a house, but a large garage or workshop.
View attachment 26045

Yeah, I have been noticing slabs that were outbuildings, metal building systems, and garages.

 

[pohnpei]

Kinda disappointed he didn't say what height it was recorded at, or whether that's a 3 sec reading or instantaneous. I read a lot of Wurman's papers last week and he's certainly quite into his theory that tornadoes' strongest windspeeds are in the corner flow region near the ground. Reading between the lines he's itching to get a 10 m agl measurement of a strong-violent tornado. Not surprising either as the research he's doing has the potential to make or break the EF scale.

Height was 258m and distance from tornado is 8km which make this more impressive than first look.
And vrot of the tornado at this point weakened a lot to 63.6kt compared with 80kt+ vrot at its peak intensity. It probably past its peak intensity for a long stretch at this point and still got relatively strong winds of 224mph by DOW.

 

[A Guy]

The NSSL is producing hindcast probabilities on their 'Spring Forecasting Experiment' page, though coverage across dates seems patchy. Rather clunky site with funny, small map boundaries, but interesting to compare:

Thursday:


Friday:



Suffice to say Thursday was less active and Friday a lot more active than forecast.

(and no, I haven't the foggiest idea what the grey report markers mean)

 

[buckeye05]

I can't stop thinking about how close this outbreak came to being much, much worse than it was. The Lincoln and Eppley Airfield (Omaha) tornadoes dropped right as they were exiting populated metro areas. Had the Lincoln tornado formed a bit earlier, it would have plowed through residential areas of the city. Had the Eppley tornado formed earlier, it would have touched down pretty much in downtown Omaha. Unreal how much worse both of those events could have been. Even Elkhorn could have been worse, as it took sharp northward turns that kept in scattered subdivisions at the outskirts of the metro, rather than entirely impacting dense neighborhoods.

 

[Equus]

Yeah watching the airport tornado just drop suddenly on the news stream and thinking how amazing it was that it waited until after downtown was insane, was wrapping up before Omaha but managed to wait just long enough

 

[buckeye05]

Also, why can't I find any videos of the Rockville and Elba, NE tornadoes? Those were the two big wedges that kicked off the main part of the outbreak, but I can't find a single chaser video of them, even though I know chasers were on them. A lot of us here watched the Elba tornado live and it was huge, but I can't find anything at all video wise. What gives?

Edit: Found one. Typed in a bunch of different search terms for the Elba tornado, and could only find this by going to Jake Heitman's youtube page. What is wrong with youtube's search function.

 

[Equus]

All i get for anything weather related now is news clips, trying to find chaser videos at this point is like pulling teeth except the teeth are fifteen pages into search results

 

[buckeye05]

All i get for anything weather related now is news clips, trying to find chaser videos at this point is like pulling teeth except the teeth are fifteen pages into search results

Yeah it's borderline unusable

 

[Chris3024]

This is absolutely incredible footage of the tornado near Tennant, Iowa.

 

[andyhb]

Home with anchor bolts (poured concrete basement with stem walls) looks to have been swept away in Minden.

 

[locomusic01]

Also, why can't I find any videos of the Rockville and Elba, NE tornadoes? Those were the two big wedges that kicked off the main part of the outbreak, but I can't find a single chaser video of them, even though I know chasers were on them. A lot of us here watched the Elba tornado live and it was huge, but I can't find anything at all video wise. What gives?

Edit: Found one. Typed in a bunch of different search terms for the Elba tornado, and could only find this by going to Jake Heitman's youtube page. What is wrong with youtube's search function.

The first shot in the video reminds me so much of the monster Coldwater Lake wedge from Palm Sunday '65.

Also, Youtube search blows chunks. It's somehow gone from almost useless to, like.. actively counterproductive. There are browser extensions that can remove some of the most egregiously unhelpful stuff (like previously viewed videos and "people also search for" and whatever other crap they're throwing in there now), but it's still really, really bad.