The Greensburg, KS, EF5 Tornado of May 4, 2007: A Case Study

In-depth discussion of the Greensburg, KS, EF5 tornado of May 4, 2007. We'll discuss the meteorology behind the event before diving into the behavior and mechanics of the parent supercell and Greensburg tornado (and subsequent tornadoes), including the modes of cyclic tornadogenesis, notable radar signatures such as a weak-echo column, the tornadoes' deviant motion, and more.
Thumbnail image from R. Fritchie via Tanamachi et al. (2012).
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Chapters:
0:00 Introduction
2:35 Meteorological discussion
23:10 May 24, 2015 analog
27:09 Event progression/radar overview
31:06 Why significant tornadoes occurred despite strong CIN
35:05 Initial "splitting" storms
38:36 Change in cyclic tornadogenesis modes
42:17 Hook echo characteristics, progression
46:58 Satellite tornadoes
48:28 Weak-echo column
52:36 Deviant tornado motion
01:00:30 Occlusion/hand-off process fueled by vorticity stretching
01:03:29 Brief discussion of the tornadoes after Greensburg
01:07:51 Summary
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Resources:
"The Greensburg, Kansas Tornadic Storm: A Storm of Extremes" - Lemon and Umscheid (2008): www.tornadotalk.com/wp-conten...
"The Formation and Early Evolution of the Greensburg, Kansas, Tornadic Supercell on 4 May 2007" - Bluestein (2009): journals.ametsoc.org/view/jou...
"Mobile, X-band, Polarimetric Doppler Radar Observations of the 4 May 2007 Greensburg, Kansas, Tornadic Supercell" - Tanamachi et al. (2012): journals.ametsoc.org/view/jou...
"Significant Nighttime Tornadoes in the Plains Associated with Relatively Stable Low-Level Conditions" - Fischer and Davies (2009): nwafiles.nwas.org/ej/pdf/2009-...
"The Influence of the Shear-Induced Pressure Gradient on Thunderstorm Motion" - Rotunno and Klemp (1982): www.atmos.albany.edu/facstaff...
"Anticipating Deviant Tornado Motion Using a Simple Hodograph Technique" - Nixon and Allen (2021): journals.ametsoc.org/view/jou...
"Historic Greensburg Supercell of 4 May 2007" - Umscheid (2010): www.dupagecounty.gov/OHSEM/We...
"Radar Observations of the 3 May 1999 Oklahoma City Tornado" - Burgess et al. (2002): journals.ametsoc.org/view/jou...
US Tornadoes article on Greensburg: www.ustornadoes.com/2017/05/0...
Cameron Nixon's article on deviant tornado motion: cameronnixonphotography.wordp...

[@ReedTimmerWx]

This is fantastic content. Seems like yesterday. Great work on these convective chronicles!

[@ConvectiveChronicles]

Thank you, Reed; I appreciate it!

[@jaymoney7772]

🤯🤯🤯

[@wesleyb_92]

Much love. Never stop chasing!

[@dwightmcqueen5771]

You the man to Reed :)

[@PFA...]

This is one of the most in-depth , intelligent channels on the internet, regardless of the topic.

[@ConvectiveChronicles]

Thank you! I really appreciate that.

[@daver00lzd00d]

I'll never be able to wrap my head around a mile wide tornado, let alone these absolute beasts 2+ miles wide! what an incredible storm that was on a mission of destruction for sure

[@craigusselman546]

That was one ugly looking tornado both in looks and effect,

[@dmeemd7787]

Anyone else ever come back and rewatch these because they’re so good and so full of information??

[@ConvectiveChronicles]

Thank you!

[@michellem.8774]

I do for sure.

[@imeep30jj]

Thank you for making this. Born and raised here in gburg and still live here.

[@cook1ezz]

Nobody makes better weather analysis videos than you. I have learned so much since I recently found your channel! This video reminded me, I'd really like to see an analysis of the Parkersburg, Iowa EF5 some day!

[@ConvectiveChronicles]

Thank you for the kind words! Parkersburg is definitely on my list!

[@Phil-eu4dr]

Tre, I was in Greensburg, Kansas that morning. It was a beautiful day. I remember it being uncomfortable at an early hour, as I needed to be in Guymon , Oklahoma by noon for a job interview. I left Greensburg about half past seven , maybe closer to eight, I was westbound on 54 , and had the hammer down. I got the job, and decided to have a beer to celebrate. I went to my favorite waterhole, and relaxed. There were at least eight warnings in Guymon that night. R.I.P. those who passed in Greensburg. Quite a resilient group of people. Greensburg lives on, after being 'taken off the map' , by mother nature. God bless.

[@ConvectiveChronicles]

Wow, that's incredible! Agreed; been back to Greensburg numerous times since 2007 and they have done an amazing job of rebuilding bigger and better than before.

[@bensainsburyweather]

Hi there! Stumbled across your channel a couple of months ago and just wanted to say a big thanks for the time and effort you go into these case studies! I'm a UK-based Storm Chaser and Meteorologist and I'm heading to the US this spring to chase for the first time and these are incredibly helpful! Keep up the good work!

[@ConvectiveChronicles]

Thanks so much! Best of luck with your chasing this spring; I hope it's an active one for you!

[@sabishiihito]

I don't know which nighttime tornado video is more terrifying, Mayfield 2021 or Greensburg 2007. I'm leaning towards Greensburg as it seems between every flash of lightning the darn thing got bigger.

[@ConvectiveChronicles]

I’d have to agree!

[@sabishiihito]

@@ConvectiveChronicles and now we have another one to add to the mix unfortunately

[@zachsteiner]

@@sabishiihito Oh yeah, rolling fork. Definitely a scary one.

[@rolandmiller5456]

Nashville's at 2:00 a.m. was pretty damn scary too. You could not even see it all you heard was breaking sounds glass shattering etc.

[@rolandmiller5456]

​@@zachsteiner I can't remember the storm chaser who said that who said it but Rolling Fork was the most frightening tornado he had ever seen. I've been through that section of Mississippi when it gets dark down there it gets dark so imagine a tornado that big or Greenberg and the weird part about it is you can't really hear it until it's too late.

[@BradleyJackson]

Amazing detail, I have learned so much from your videos as to why/how these events occur. Thank you for all your work!

[@ConvectiveChronicles]

Thank you so much!

[@evirs]

That is some absolutely INSANE radar data on the Greensburg tornado-genesis... you really get a feel for how intricate the storm scale processes are and why the conditions need to be absolutely perfect for your violent EF4/EF5s to spawn.

[@giarc0]

Thank you for taking the time to produce this for all of us. Impressive work. 🌪️

[@ConvectiveChronicles]

My pleasure; thank you for watching!

[@peachxtaehyung]

Dude you're blowing up! (Rightfully so!) Congrats!

[@ConvectiveChronicles]

Thank you!!

[@weathermanofthenorth1547]

This is an awesome case study! Quite organized, and I like that you are teaching the viewers lessons and facts that they otherwise would not know. I also like that you showed how this occurred despite a strong CIN presence.

[@ConvectiveChronicles]

Thank you so much!

[@Brian.Gardner]

Another excellent analysis. I’m binge watching all your videos now. 👏

[@ConvectiveChronicles]

Thank you so much!

[@mrecto5187]

I’m trying to learn as much as possible about tornadoes and storms behaviours and even i don’t understand everything you say just yet , i can say its really educational. I will keep watching your works cuz they will definitely help me understanding what’s going on during a storm.Thank you for these videos. I greatly appreciate them. I’d love to do some storm chasing for photographies someday and i’m not taking this lightly. So again thank you and keep up the amazing work.

[@ConvectiveChronicles]

Thank you so much!

[@speakerpythia]

This is extremely comfy watching for me. Thank you for yet another amazing video.

[@ConvectiveChronicles]

Thank you for watching!

[@ezera7616]

You really outdid yourself, Trey. I learned a ton about plains setups from this video, so thank you very much!

[@ConvectiveChronicles]

Thank you so much!

[@SvrWxArchive1807]

Another banger from the man himself! Incredible. I's be interested in some more historically significant tornado events too, I know there is not much data for many of them but it would be interesting. Examples: March 18, 1925 Tri-State Tornado April 11, 1965 Palm Sunday Outbreak April 3, 1974 Super Outbreak June 3, 1980 Grand Island, NE tornadoes March 13, 1990 Hesston-Goessel Tornado April 26, 1991 Plains Outbreak etc.

[@ConvectiveChronicles]

Thanks so much! Those are all on my list. All of those are high on my list; there should be enough research papers, etc. on these events (and we have Tornado Archive to help out) that I’ll be able to fill in the data gaps.

[@StormChaserLoganParham]

Incredible work as always! Enjoyed every second

[@ConvectiveChronicles]

Thank you!!

[@Austin_Dale]

Man you are a blast to listen to. I could just listen to you talk about the structure of storms all day.

[@ConvectiveChronicles]

Thank you for the kind words!

[@betterthanmost9549]

A lot of this stuff goes over my head but I can't help but watch every upload I love it.

[@ConvectiveChronicles]

Thank you! Always feel free to ask any questions you might have on the videos; I'm happy to help.

[@deandracarter8468]

The fact that this storm spawned other large tornadoes quite quickly after the Greensburg one is just wild. Thank you for sharing this. I'm learning so much from your case studies.

[@ConvectiveChronicles]

Really happy to hear that; thank you!

[@runt9]

A phrase similar to "wiped off the map" gets applied to many towns and cities heavily impacted by tornadoes throughout the years. I heard it all throughout my youth about Jarrell, growing up in Texas it was the storm with the most notoriety. But to see a tornado, literally wider than the town itself, destroy ninety. five. percent. of the town is the only time I think that phrase appropriately encompasses what the storm did, based on what I've seen. That said, looking into the recovery and rebuilding project into a completely green city was also fascinating. This tornado was certainly insane on many levels, not the least of which reaching such an insane width, almost rivaling El Reno. As per usual, wonderful case study. I've caught up on all of them at this point and thus I can truly just get excited for each new one as they come around!

[@ConvectiveChronicles]

Thanks so much! I’ve had the pleasure of visiting Greensburg in the last year, and it was awesome to see how they’ve rebuilt as a greener, better city. The scars definitely remain with ample empty lots and traces of old foundations, but otherwise you’d never know what occurred there a decade and a half ago.

[@runt9]

@@ConvectiveChronicles Yeah one of the harrowing things I read while digging in a bit more on my own was this bit: "as the 2000 census found 1,574 residents, while only 777 were recorded in the 2010 census". Despite the powerful rebuilding effort, the population is still half what it was before the tornado as so many people had to find new places to live elsewhere. But a strange silver lining about complete destruction like that is the fact that when you have a clean slate to work with, you can be ambitious with how you build upon it.

[@crazycatlady5629]

Awesome video as always! Thanks for sharing your knowledge with us.

[@ConvectiveChronicles]

My pleasure, thank you!

[@alexrheinheimer8682]

Hey Trey, wonderful video as always! I would love to see you go through the environment of the 2011 el reno/piedmont ef5. I know Leigh Orf of my alma mater UW-Madison used that environment for his supercomputer tornado simulations,so I would assume it was a very well sampled environment. Either way keep doing what you’re doing, I’m currently a second year medical school student and your channel has been an amazing way to learn a new science when I need a break from medicine😂

[@ConvectiveChronicles]

Thanks so much for the kind words! El Reno 2011 is high on my list; Dr. Orf's simulation of this storm is a masterpiece!

[@bdunk914]

If you didn’t get the notification your request has been granted by the most knowledgeable curator of this channel! I present to you Case Studies El Reno 2011 now playing

[@cameronwood5692]

Awesome video yet again. Favorite channel on KZbin!

[@ConvectiveChronicles]

Thank you!!

[@fitfogey]

This was amazing. I’ve never heard of deviant tornado motion or some of the other terminology in this video. I just assumed that tornadoes kind of just move in a track and then can just move randomly at times so you can never just count on what the path may be. Great analysis.

[@ConvectiveChronicles]

Thank you!

[@jdedrummer4]

I always associate this tornado with the Stormchasers show on Discovery because Sean Casey predicted a tornado would hit Greensburg.

[@peachxtaehyung]

Wow really!? That's crazy

[@Boskibro]

@@peachxtaehyung wow he predicted a tornado would kit a town on the border of KS and OK!!! Nobody could have seen that coming.

[@peachxtaehyung]

@@Boskibro with it being an exact town name and the fact that this day wasn't expected to be anything big that is crazy that he predicted it lol. If it was like the event for the next day I would agree it's not really crazy he predicted it. But as I said this event wasn't forecasted to be a big day or anything

[@bigaaron]

​@@Boskibro You sound uneducated

[@Celon549]

Same here. I remember that it was Reed Timmer's crew that had gone elsewhere expecting a potential storm, only for nothing to happen, until learning about the Greensburg tornado from Casey.

[@willarasmith4893]

So glad you talked about the tornadoes that occurred after the Greensburg tornado. The Trousdale tornado tossed a very large combine tractor almost a 1/2 mile. I personally think it was the strongest of the 3 large twisters this storm produced (notice the velocity scan are off the charts at some points), it just travelled opened open land for the most part and didn't hit much. It's worth mentioning the EF scale is misleading when it comes to the power or strength of a tornado. It bases off of damage to structures on the ground. It doesn't take into account actual measured wind speeds (which, admittedly, are hard to get and/or trust). This part of the meteorological field really needs to be updated (and is currently under review from what I understand). Excellent video as always. I was waiting for this one. Watched this unfold on live TV when it happened.

[@ConvectiveChronicles]

Thank you! I agree; I do think Trousdale was stronger than Greensburg. They are in the process of amending the EF scale to include more damage indicators for rural areas, mobile radar data, etc.

[@cubby091398]

I am so happy more damage pictures have surfaced over the past couple years or I would have kept thinking the Greensburg tornado was only a marginal EF5 tornado. The new damage photos I have seen put the Greensburg tornado solidly in the EF5 category. I actually believe the other 3 huge wedge tornadoes were capable of at least high-end EF4 tornado damage. Of all the 4 huge wedge tornadoes I believe the Macksville tornado was the strongest tornado based on sweeping a well-built home away and throwing a jeep 3/4 mile and was completely mangled beyond recognition. While the Greensburg tornado was impressive I wouldn't say it was the strongest tornado ever.

[@nathanlujan1628]

This one hits close to home I grew up in Wichita but we’d always meet my grandma in greensburg to meet when we would go stay with her she lived in Oklahoma near guymon it’s crazy to pass through greensburg and see how much has changed since the tornado

[@MTS930]

After driving through Greensburg a couple years back it's amazing how well the town has recovered, but there are plenty of empty lots where people decided to move on.

[@ConvectiveChronicles]

Yep, visited there last year and had the same thoughts.

[@sb6953]

Thanks for making these videos, in all my years of living in the same city, none of us ever worried about a tornado even coming within 30 mins of us. We got hit by our first tornado in the middle of the night this year and I get terrified as soon as I hear thunder now. These videos make it all somewhat less terrifying!!

[@ConvectiveChronicles]

I’m happy to hear that! Thank you!

[@wayloncapps9480]

Love your videos. Like everyone else I find it your analysis superb! You dumb it down enough so that people like me can understand it. I’m sure that’s not easy to do. I appreciate your hard work!!

[@ConvectiveChronicles]

Thank you so much!!

[@TAStormChasing]

Another great case study. Beast of a supercell. Thanks for the upload!

[@ConvectiveChronicles]

Thank you!

[@TAStormChasing]

@Convective Chronicles Got me thinking. Is there a record that is held by a cyclical supercell with the most produced tornadoes? Have a good one 👍

[@ConvectiveChronicles]

That’s a great question…I’m not 100% sure, but I can’t think of any cases off the top of my head that come close. Of course, the number of satellite tornadoes with Greensburg kind of artificially bumped up the tally a bit. Regardless, the Greensburg storm has to be up near the top for most tornadoes produced from a single storm.

[@windwatcher11]

Reminds me of Jordan F5 a bit, the loop, the satelite anti-cyclonic; but quite a few differences, too. (More of a hi-CAPE, lo-shear event.) Great study, Trey! Piques my curiousity, as usual! You're a heckuva teacher.

[@ConvectiveChronicles]

Thanks so much! The Jordan case definitely had some similar aspects to it.

[@SpacemanSpiff17]

Banger of a case study Trey!

[@ConvectiveChronicles]

Thank you!

[@jamesbaker7166]

Thanks,I really appreciate your breaking down the mechanics of severe Thunderstorms

[@ConvectiveChronicles]

Thank you for watching!

[@imquokkacola]

I would be very interested to see you do a case study on the Elie, Manitoba F5 tornado from 2007. It's not a very well-known tornado, but it was extremely unique in its damage path and overall characteristics.

[@ConvectiveChronicles]

It is high on my list!

[@laureng6412]

I love your case studies of storms like this, they are very well researched! Could you do a case study on or analysis of the tornado that hit Raleigh NC in April 2011? That's the tornado that almost hit my house and that got me into meteorology!

[@ConvectiveChronicles]

Thank you! I believe you're referring to the April 16, 2011 event...I do have that event on my list!

[@laureng6412]

@@ConvectiveChronicles looking forward to that then!

[@wxholly]

Really looking forward to this one!

[@Cdunlapweather]

This is one I’ve been looking forward to

[@tornadoclips2022]

Same. This is the most scariest tornado in my opinion

[@ainsopholli439]

Phenomenal!! I just graduated with a meteorology degree and this is really helping me strengthen my knowledge while I try to find jobs :> Keep up the great work!!

[@ConvectiveChronicles]

Thank you so much! Best of luck with the job search!

[@quik1515]

Such a great breakdown as always! Keep em coming! Here in Kansas, we pronounce it Trues-dell if that makes sense. I chased this once it got near Great Bend and to the north east

[@ConvectiveChronicles]

Thank you; many more on the way!

[@jonasmassa23]

Hey, great video! I love your channel and how in depth you go into information. Would you be able to either do the outbreak of March 2, 2012 (which I’d prefer)(Henryville) or November 17, 2013? I’m from Indiana and those outbreaks, I remember like yesterday.

[@ConvectiveChronicles]

Thank you! Henryville is actually next up on my list! 11-17-13 is on my list, as well.

[@jonasmassa23]

@@ConvectiveChronicles Cool! Thanks for responding and ill be looking out for it!

[@dmedme9268]

Absolutely excellent work!

[@ConvectiveChronicles]

Thank you!

[@Meteor_5207]

Awesome analysis. Can you do a break down of the 2011 Chickasha Oklahoma tornado some time? Arguably an EF-5 but it's rated an high end EF-4.

[@ConvectiveChronicles]

Thank you! The 2011 OK outbreak is on my list!

[@hgbugalou]

Great review as usual sir.

[@ConvectiveChronicles]

Thank you!

[@DanRoss11]

Awesome analysis! Love all your videos, such great resource. If you ever do the Fairdale, IL high-end EF4 I'd happily contribute my photo(s) if you're interested. Great example of a supercell taking advantage of increased SRH near a warm front.

[@ConvectiveChronicles]

Thank you! Fairdale/Rochelle is definitely on my list; one of my favorite events of the last decade and an absolutely beastly tornado. Not sure when I will get to the case study, but I would definitely be interested in your photos!

[@DanRoss11]

@@ConvectiveChronicles Very beastly and scary - I lived less than 15 miles from its path at the time! I sent my email to your IG account. Look forward to your next video

[@austinmccoy9743]

Fantastic analysis as always. I have two questions that come to mind after watching: 1) So if I understand correctly based on the video, the BWER indicates the mesocyclone, and the weak echo column indicates the tornado. Is there a reason these wouldn't be coincident with each other? 2) The maximum width of the Trousdale tornado was 4.1 km (2.56 mi) according to the article you showed, so would that not make it the 2nd largest tornado in history, since Hallam was *only* 2.5 miles wide?

[@ConvectiveChronicles]

Thank you! The BWER essentially correlates to the "vault" region of the supercell aloft, part of the strong updraft that is situated at the interface between the updraft core and the inflow region of the storm. Any tornadic vortex occurs from the core updraft, which is usually situated off to the left of the BWER, hence the offset. Yes, the 4.1 km width of the Trousdale tornado would technically make the second largest tornado in history behind El Reno 2013. I think the reason it's not widely recognized or mentioned in that regard (at least among the general chaser/weather enthusiast public) is because there's really no video of it showing it at that size available, and Greensburg took the cake on that night in terms of noteworthiness. But yes, if that 4.1 km width is correct, Trousdale would be 2nd behind El Reno 2013.

[@austinmccoy9743]

@@ConvectiveChronicles Thank you for your response, that helps clear things up!

[@michaelonesty]

Hey Trey, another incredible video. May I ask: what is the source of those shortwave kinks within a larger wave? Why is the trough flow become slightly less laminar in those areas?

[@ConvectiveChronicles]

Thank you! Shortwaves are basically pools of colder air aloft. Isotherms cross the height contours within a shortwave, yielding an upper-level front. Just like on the surface map where frontal zones are situated within pressure tongues, these temperature gradients aloft cause some slight kinks in the height contours aloft, which is how we can pick out shortwaves on a 700 or 500 mb map.

[@michaelonesty]

@@ConvectiveChronicles Thank you sir!

[@UpperlevelJeffstream]

Trousdale is pronounced (Troosdale). Im from that area. Keep up the fantastic in-depth content! :)

[@ConvectiveChronicles]

Thank you!

[@Luzy_Garcia]

Dialect is important.

[@Kevinimages]

These are awesome videos, keep it up!!

[@ConvectiveChronicles]

Thank you!

[@klk1900]

So my theory on the weak echo hole part of it may be the size of the greensburg tornado. The DOW radar may 3rd event; was (3cm wavelength) -(50-150m low beam height) (Peak power: 250kw) (distance from radar: 3-8km). and the 88d was 10cm wave length (300-1km low beam height) (750kw peak power) (17-59km from radar). The resolution of the 88d nearly being 1mile x 1mile cube. Meaning it can’t see anything smaller or it can but It will be within a pixel. The greensburg tornado being 1.7miles wide +/- some tenths. The WEH may have shown up on the 88d being the tornado was bigger than that 1 x 1 mile resolution. - keep in mind the Dodge city radar KDDC @0.5Deg the beam Height:2’400KFT at greensburg being its 36miles from dodge city. That’s the lowest level it can see -- the Wichita radar beam height @0.5 degree is 9’800-10’000kft over greensburg.

[@antarcticbicycle9005]

Another day, another banger Trey

[@ConvectiveChronicles]

Thank you!

[@Brian.Gardner]

59:12 left surge almost looked like it encountered strong outflow blast from the storm to the NW.

[@michaelistheman1533]

Can you do the chetek Wi EF3 tornado on May 16 2017?, it was the longest tracked tornado in Wisconsin I believe,... the atmosphere really surprised meteorologists that day

[@ConvectiveChronicles]

I will add it to the list!

[@Rationalmethod995]

Gotta buy you a beer for this one. Excellent work.

[@ConvectiveChronicles]

Thank you so much! I really appreciate it!

[@shaunmartin2925]

Classic LLJ increase after sunset and that provided insane inflow and low level shear and supercharged this supercell to turn it into a tornado producing monster.

[@wolfywise]

The RFD surge leading to the Trousdale wedge is so prominent.

[@toniwanta82]

The tornado was 1.7 miles wide and was a wedge potentially bigger than Greensburg itself

[@StayPrimal]

Jee, its a beast. Thx for the video it will be a fun one

[@stunter4everfsls]

What a GREAT video!!!

[@ConvectiveChronicles]

Thank you so much!

[@nalla1782]

could the WEH be correlated with the size of the tornado, not necessarily just the intensity? If I remember correctly, the 2013 El Reno had an exceptionally large WEH as well, which would make sense.

[@ConvectiveChronicles]

Yes, the WEH is generally best correlated with the size of the tornado.

[@patricklaurojr7427]

Insane night imagine being in middle of Kansas with this monster coming at u all can do is hear it coming all lights out pitch black and onky way see it is from lightning ontop of being surround by 3 other monsters 1 of them was bigger. Plus after it passed Greensburg it did a crazy loop like wanted come.back at town. I wish it wasn't at night so can really get a look at it

[@junkiexl86]

1:01:00 Looks like it was in the process of weakening/shrinking as it moved into Greensburg. I can only imagine how much worse it would have been had it hit Greensburg at full strength and width, as seen south of the city.

[@ConvectiveChronicles]

It was still quite the beast and destroyed 95% of Greensburg. The EF5 damage indicators came from town, so it was still close to peak intensity as it went through Greensburg.

[@Snowstar837]

Do these "mode 2" tornadoes have anything to do with the tornado being more firmly centered beneath the meso/updraft?

[@ConvectiveChronicles]

In essence, yes. The difference between mode 1 and mode 2 cyclic tornadogenesis seems to be the result of how closely matched the motion of the tornadoes are to that of the main storm-scale updraft/downdraft. The mode 2 tornadoes occur when when their horizontal motion closely matches that of its associated updraft/downdraft. The Tanamachi et al. paper goes into detail on this.

[@SimonGruberSays]

Given that it's possible that the Greensburg Tornado was stronger than the Bridge Creek/Moore Tornado (based on the WEH visibility on radar) and, that the Trousdale Tornado was possibly even stronger still, would there be a case to be made for the Trousdale Tornado being the strongest ever recorded?

[@ConvectiveChronicles]

I wouldn’t say with certainty that it’d be the strongest ever. Would’ve been awesome to have a mobile radar on that storm post-Greensburg, we would’ve been able to get a really good look at it to make a more definitive statement. Definitely could be up near the top though.

[@ConvectiveChronicles]

@@michaelorme7501 Can't even imagine the aftermath if that were to occur

[@Michael-gi5th]

Great work man

[@ConvectiveChronicles]

Thank you!

[@aaronjones1469]

Awesome case study.

[@ConvectiveChronicles]

Thank you!

[@MightyMuffins]

I actually forgot about how active May 5th was. Strange as that falls on my birthday....over 100+ tornado reports is remarkable. Well either way this event as I mentioned in another comment section is one of the thing I remember was talked about that Fall in 07 as a Freshman METR student...well I brought it up in general convo when possible. It was interesting how some people (mostly ones that dropped the major) didn't know about it and I was stunned. I remember trying to find video of this storm and in the early days of youtube it was few and far between. Honestly, I think the other problem was there was very few chasers out there that, 1. got good video of the tornado at it's peak after dark and 2. lot of video was on potato video. The one video you have there from Weather Beat is the one I remember most fondly and they got the most famous video of the tornado and were in the most PERFECT of perfect positions to film it and they kind of had to stop too cause of the surging RFD behind the tornado I think was starting to wreck their view of the tornado and having to deal with 80mph crosswinds. I still can't imagine what it's like staring down a tornado THAT FUCKING HUGE in the dark and hell even the chasers that got the one after Greensburg. I mean that's beyond balls and to only see it lit up with lightning behind it as your only light source is INSANE. Actually, well no, there's one thing these potatoes-like video/cameras (APS-C and under) don't exactly show is that in the Midwest you can still get residual sunlight on the horizon for a good couple hours past Sunset which is cool so you could make out a faint outline in person of it but on video and camera quality at the time and settings on them not being like a full frame camera....yeah it's hard to see it, only when backlit. I forgot this storm produced 22 tornadoes and that's just freakish on it's own. I think one thing people that are current chasers or rather....post-2013 chasers that didn't chase in the Midwest from the 2004-2013 season don't understand how weird and insane it was to see wedge tornadoes....like I mean TRUE wedge tornadoes like this. It's not often these days we see tornadoes over a mile wide but man that decade or so of outbreaks had some wide and I mean WIDE tornadoes and we haven't seen that I think since that in over a decade which is strange. I think that's one thing that modern chasers don't understand that I think veteran chasers like Reed and others have the experience over....they know and have seen true fat tornadoes and in lies the danger I see and it's inevitable where we could see chasers parallel chasing a tornado that seems small but grows so fat and wide quick. I mean look at the paths from Greensburg and the others there and like what unfortunately happened to the TWISTEX crew on that tornado......there's also SO many chasers these days out there compared to these 2004-2010 days and it's only a matter of time where we see and "inexperienced chasers" (one that never have chased BEASTLY night-time fat tornadoes) see what a TRUE 1-2 mile wedge tornado can do and how insanely dangerous it is to chase that in person again....and that is the scary thing where people could be caught off guard again.

[@ConvectiveChronicles]

Yeah, I often wonder the quantity/quality of videos we'd see if Greensburg happened today. Likely would have a bunch of chasers much closer to the tornadoes and would have some epic footage. And yes, still waiting to see a return to a good frequency of very large tornadoes. Hopefully, we don't see any chaser incidents with large tornadoes in the future, but with the proliferation of chasers in recent years, it is probably bound to happen.

[@MightyMuffins]

@@ConvectiveChronicles i mean Trey unfortunately you and I know something bad is bound to happen with SOOO many out there these days. Tornadoes can do some weird freaky stuff on the rare occasions and like this and El Reno and other fat tornadoes...when they get big...they can get big faster than you can react.

[@maryjohansson3627]

Great presentation.

[@ConvectiveChronicles]

Thank you!

[@charlieeells6120]

the wind really picked up today yesterday fyi; air pressure is changing slow rapid sound.

[@olbailey8606]

This is fascinating

[@ConvectiveChronicles]

Thank you for watching!

[@scronstage]

Any chance you could do one of the Robert Lee Texas tornado?

[@ConvectiveChronicles]

Hoping to do a case study of that multi-day stretch of mesoscale days in Texas at some point

[@Spade_WX]

Hello! I was wondering if you can do an EF0-1 outbreak around the St. Louis area. It was from a large cell with 2 warnings at once. I was scared as I am in STL metro

[@ConvectiveChronicles]

I’m not sure which event you’re referring to

[@Spade_WX]

@@ConvectiveChronicles I’ll send a link

[@Spade_WX]

@@ConvectiveChronicles this one kzbin.infoplRGwfFrCDg?feature=share

[@DarkRakus]

This Supercell was crazy... insane content

[@ConvectiveChronicles]

Thank you!

[@jasonperry7970]

Im trying to understand how a downdraft rfd surge causes an even bigger tornado updraft in a new tornado? Is this like the old physics trick of dropping a basketball with a golf ball on top? Where a heavy falling airmass impacting the ground causes small airmasses on the leading edge to shoot out/up?

[@ConvectiveChronicles]

An RFD surge can help balance out intense inflow coming into the storm to allow for tornadogenesis to occur

[@krzy1867]

If greensburg was able to annihilate an entire town not even at peak width, who knows what trousdale could have done at it’s peak width

[@krzy1867]

Also the last time a defined WEH has been seen on radar (to my knowledge) is the Lockett EF3 of last year. It had a very defined WEH before hitting lockett

[@krzy1867]

Ironically also on May 4th

[@ConvectiveChronicles]

On WSR-88D? If so, that’s impressive. There are lots of cases where a WEH shows up in mobile radar data but very few on WSR-88Ds.

[@charlieeells6120]

boyz you are going to be busy fyi. godspeed and may you find your way.

[@tornadoclips2022]

Ohh this tornado gives me chills every time I hear the name. Most scariest tornado in my opinion

[@colin7244]

17:34 thats what im saying the drought really makes the eml too strong and can just cause the whole event too not even produce a single thing which is a nuclear cap or a less intense drought with a more isolated to scattered eml would be the set up we would want to see for a great plains severe weather event

[@mitchconner2021]

With all the RFD and inflow surges it was like the storm was breathing ya know? Weather is crazy.

[@donovanburrell2354]

Hi, The Greensburg tornado is the perfect night time twister

[@colin7244]

Was the cap during this event as strong or stronger than the april 27th one?

[@ConvectiveChronicles]

It probably was stronger, it just didn’t matter too much because of such strong low level shear with a mature supercell ongoing.

[@colin7244]

@@ConvectiveChronicles no wonder why that supercell was all by itself and produced 3 violent tornadoes and the second one of the 3 could have been an ef5 if it obviously hit a well constructed structure but im glad the other 2 ef3’s were out in open field terrain

[@nathanlujan1628]

You should do the Andover tornado that happen last year or the one that happened in the early 90s or the haysville Kansas tornado of 99

[@ConvectiveChronicles]

All are on my list!

[@nathanlujan1628]

@@ConvectiveChronicles look forward to them sir

[@JPDrums1990]

I am not a meteorologist, storm chaser or a trained storm spotter by any stretch of the imagination; I am just a severe weather enthusiast but if I were chasing that night and saw the outline of that monster, I’d high tail it and get the heck outta there.

[@cs77smith67]

I know your stuff so lete ask u, what would it take to make a tornado 🌪️ 3 miles wide with winds over 🌬️ 350-420 MPH?

[@ConvectiveChronicles]

Lots and lots of streamwise vorticity with strong low level instability

[@cs77smith67]

@@ConvectiveChronicles wow you're so smart 🤓 I wonder 🤔 what would make those types of conditions come together? And if it ever happen in the past? I'm sure it has I bet

[@ConvectiveChronicles]

@@cs77smith67 It would have to be a really potent system...April 27, 2011 is about as close as we have gotten to a "perfect" event, but we'd probably still need more potency than that.

[@spencertaylor2580]

When/where was this??

[@ConvectiveChronicles]

Did you even watch the video? Even just glance at the video title?

[@FreshEDMMusic]

Let's goo! Content

[@Ithaca-vv5dy]

Where is the best place to learn how to read a sounding?

[@ConvectiveChronicles]

I have a full video series that breaks down all you need to know about how to read soundings: kzbin.info/aero/PLnjboQ2ku8GDI9DGcqR8d9sr0sZKhH-qX

[@MrBlueboy6666]

trey you rock

[@tupacalypse88]

That's a beast daymnn

[@Maplelust]

absolute monster!

[@darkdreamer921]

I love your videos, but you sound like Brian Griffin with a slight cold.

[@ConvectiveChronicles]

This may be the best comment I have ever seen.

[@kricetispies732]

Plz teach me more!

[@JustinLHopkins]

It’s pronounced ‘trewsdale’ lol. I’m from Kansas. Just helping you out. 😊

[@ConvectiveChronicles]

Thanks…yeah, I’m not from the Plains, so I get place names wrong all the time…

[@myria9644]

hey thats my state

[@beezlebub3955]

Yassssssss!!!