02/28/07 DISC: KS/MO

[afischer]

NWSTOP has rated the Colony-Lone Elm KS tornado a strong EF1, with a path length of nine miles and path width of 200-300 yards (briefly up to 1/4 mile).

http://www.crh.noaa.gov/crnews/display_story.php?wfo=top&storyid=6353&source=0

[Jeff Snyder]

Was this the "violent wedge" that I was hearing about, or was that another tornado? IIRC, there was another tornado reported farther ENE (in EAX's CWA), but I'm not sure which one was invoking the dire language in the warning texts and severe weather statements?

[Kenny Drake]

Well I think there are plenty pictures of the "violent wedge" floating around. I may be wrong, but I dont think any wedge tornado will be weaker than an EF2. The tornado afischer mentioned was probably another one. I remember looking at radar Wed evening and there is no way the supercell with the "violent wedge" was only putting down an EF1, the hook echo was almost as classic as the 5-3-99 echoes prior to hitting Moore.

[afischer]

I was within a mile of the Colony-Lone Elm tornado when it initially developed. It started as an ugly multiple vortex and then started changing shapes, sometimes looking like a wedge. It looked rather weak to me.

The stronger wedge seemed to be a separate tornado that developed in Linn County around 735pm. This is the one that did more significant damage and took on a solid wedge appearance north of Blue Mound. And Jeff is right, that is EAX's CWA... should be interesting to see their survey when it comes out.

[Chris Hayes]

Well I think there are plenty pictures of the "violent wedge" floating around. I may be wrong, but I dont think any wedge tornado will be weaker than an EF2. The tornado afischer mentioned was probably another one. I remember looking at radar Wed evening and there is no way the supercell with the "violent wedge" was only putting down an EF1, the hook echo was almost as classic as the 5-3-99 echoes prior to hitting Moore.

Size of a tornado doesnt matter when it comes to strength. Two extremes of this are the Pampa and Happy Texas tornados. The Pampa tornado was narrow but very intense, and rated F4. The first Happy Texas tornado of 5/5/02 was a borderline wedge tornado, but it was very weak. If you watch it on video, it has very littel visible rotation.

[Brian Stertz]

Yes that is correct...the Linn Co. tornado was indeed in the very strong or possibly violent category . Damage video shows that houses were swept from foundations. Sure looks EF4 damage to me...but construction of the houses was not exactly known. The big tornado also seriously mangled a sizeable power sub-station and brought down the adjacent high tension lines/towers. I imagine the damage survey will be forthcoming shortly from the NWS Pleasant Hill. I believe this nasty Linn Co. tornado was the third tornado segment cycle of the very intense supercell (at least after watching the SR velocity images that night).

[afischer]

Yes that is correct...the Linn Co. tornado was indeed in the very strong or possibly violent category . Damage video shows that houses were swept from foundations. Sure looks EF4 damage to me...but construction of the houses was not exactly known. The big tornado also seriously mangled a sizeable power sub-station and brought down the adjacent high tension lines/towers. I imagine the damage survey will be forthcoming shortly from the NWS Pleasant Hill. I believe this nasty Linn Co. tornado was the third tornado segment cycle of the very intense supercell (at least after watching the SR velocity images that night).

I haven't reviewed radar yet from this event at all yet but this makes sense to me. I was out of position for the tornado near Neosho Falls, but when I got out ahead of it north of Iola I didn't see any tornado whatsoever. (On that note, there seem to be conflicting reports w.r.t. what happened between Neosho Falls and Colony; should be interesting to see a damage survey if ICT comes out with one). Anyway, it appeared to me that the storm cycled a brand new tornado there east of Colony which is supported by the TOP storm survey. Then between about 7:20 and 7:35 (though some of that time I was out of position again), I didn't see any tornado whatsoever. A radar loop I saw on Fox 4 news the day after seemed to show the storm cycling a new meso at that time, which would correspond with the down time between tornadoes. Then the third tornado was apparent in a hurry shortly after 7:35pm in Linn County.

The damage north of Blue Mound was extensive (what appeared to be a small home completely blown apart and spread across the highway), but like Brian said we don't know the quality with which the home was built.

[Wesley Luginbyhl]

The rating on the Colony tornado doesn't surprise me. We saw a lot of power flashes, but in all my video stills the funnels are still pretty far of the ground and there is no debris visible in the air (about 7:01). There was definitely a fresh smell of torn up vegetation in this area when we drove through. The mulivortex that followed to the East of Colony might have been a little bit stronger than the Colony considering it duration it was down (about 10 mins by my video, 7:05 to 7:14) and size. When we stopped to try and set up tripods at 7:15, it had lifted but the was large bowl lowering beginning to take shape. This was the beginning of the Blue Mound tornado. After this point there was atleast a large lowering spotted everytime the lightning flashed. The east road we were using was closed so we had to drive North which put us within a couple miles of it. There were points when we came over hills you could see a lowering that was atleast a 1/4 mile wide and was 90% of the way to the ground. It looked to be skimming the surface at this point. The large lowering then made obvious connection to the ground as well as having atleast 1 satellite tornado. I really expect the Blue Mound to be atleast EF-3 by what we saw that night and the the video of the damage shown on tv. Thats just my opinion.

[Scott Blair]

Afischer is correct in his assessment regarding the "wedge" tornado within the Topeka CWA. The tornado within our CWA was weak for the most part per damage survey and photo analysis. I was present during the reported wedge tornado and I observed what most individuals observed which was a concentrated updraft region (per tornadic circulation) that was characterized by lots of updrafting/rotating scud. I'm skeptical this tornado ever truly wedged out for any great length of time, but more likely filled in at times with the appearance of a wedge tornado sporadically during lightning flashes. With lightning serving as the only existing light, it made it quite difficult for the observers present. If this was a true wedge tornado, I would have expected to see much more significant/consistent evidence in the way of photos, which just isn't the case.

Now Brian is also correct with regards to the strong/violent strength within WFO Pleasant Hill's CWA. This tornado will likely be rated an EF3/4 from what I understand. It appeared this tornado was stronger, perhaps due to INVOLF baroclinic boundary interaction and strengthening LLJ. Hard to say.

SFB
http://www.targetarea.net/

[fplowman]

Im very confused with this chase. Part of my issue was i didnt have radar feed in the vehicle on this one. i started driving south kinda towards coffeyville when i seen the initiation begin south around chanute..

I shot back north, chasing by structure and site. Listening to the NWS radio it said there was a thunderstorm targeting through Yates Center

So i starategically drove as fast as i could North on 169 and went west through Leroy ( 58 hwy ). I set up about 3 miles to the West of Leroy.

I filmed a wall cloud and a lowering coming straight at me. It was High precip and Hail from dime to a little larger than quarter followed.

I become somewhat un nerved as the hail came down and we jumped in the car and drove into Leroy ( 58 Hwy ) to take cover somewhere from the larger hail. I must say I dont remember the time but it was dark.

Right after the hail subsided we proceded East back towards 169 hwy

The hail was litering the HWY ( 58 ) at this point and appeared as if it had snowed for almost the entire path to 169 Hwy. Im unsure if this is one storm cell with multiple mesos or it took a turn more Easterly.. The NWS basically had it on a more N - N - NE path.

When a mile or so from 169 Hwy on 58 Hwy We noticed what folks are calling the Colony Wedge in the lightning. It was my belief at the time this was the same storm or meso we initially intercepted west of Leroy.

About midpoint between Leroy and Colony We could smell a strong odor of Pine trees (prior to seeing the supposed wedge in colony)that were obviously uprooted. Ok so my question is was it winds from the outflow from Colony bringing this to us or was it at the time as we thought we were in the damage path of this tornado.

We thought the later.. we thought the storm we intercepted West of Leroy dropped the tornado shortly after Leroy on a more easterly path and then did what it did in Colony.

Either way im with Scott Blair on this that the scud and updraft appeared to POSSIBLY be a giant tornado.. And after seeing the pics here in this thread we can definetly asume that it was.. But with the limited visibility mostly due to darkness etc.. We couldnt be definetly sure what we were seeing was a wedge a mulit votice tornado or whatever at the time.

Hopefully my post doesnt confuse anyone but shed some light of what I experienced.

[Mike Parker]

Scott and afischer are dead on in their assessment of the nights events in and around the city of Colony. Scott you are very accurate in stating that it was very difficult to judge accurately what the tornado/wall cloud was doing at any specific moment due to the blackness of the night. There was literally NO indication of any structure at all until lightning would back light the storm. From my location (exactly 3 miles south of Colony) it was almost impossible to detect ground circulation. The amount of visible light during most flashes was so quick that unless you had your eyes trained right on the storm it was hard to pick out exact details of the tornado. As you can see from my pictures in the REPORTS section, the tornado had the appearance of a wedge and then, within the next lightning flash or two, it had lifted completely up as it passed HWY 169 and entered Colony. I could never detect any rotation due to the fact that there was not enough constant light to judge movement by. I cannot testify to the "violence" of the rotation. All I could do was report what I could see at that moment.

Now that the sun has risen and the damage/lack of damage can be seen and judged, maybe the description of a "wedge" might not be the most accurate of adjectives. All I do know is that from the very limited amount of information available to me in the field (basically my eyes) I believe that the description of "wedge" was appropriate at that time for describing the tornado east and west of Colony but not directly over the town. Now, I was not the one that called ICT or any other NWS office but I did use the term "wedge" in my report here so that is why I have chimed in.

I went out and looked at the damage around Colony yesterday and to my untrained eye, it appeared that the damage path was spotty. It seemed that the tornado might have been hopscotching around the country side. Obviously, if that is the case, then this was not a true "wedge" tornado.

The scary part to me is that as the tornado/wall cloud/elevated mulitvortex/whatever you want to call it was moving into Colony, the radio was reporting the tornado to be everywhere BUT where it was. It is truly unfortunate that there was damage but thank God there was not injuries or deaths. Bottom line is that night chases are not conducive to accuracy in reporting sometimes. I would cut a little slack to those who may have used terminology that was a little dramatic for the occasion. It was a surprise to be chasing such a wild storm to begin with and an honor to be witnessing such an act of mother nature.

[fplowman]

Does anyone have a radar pic or data of this event? Preferably with stormtrack info i would like to see it so I know what the hell happened to me in relation to my experience west of Leroy and then again at Colony...

[Mike Parker]

I managed to get a couple of grabs. Both of these were right on top of Colony.

http://i14.photobucket.com/albums/a331/weathernut07/02-28-07.png

http://i14.photobucket.com/albums/a331/weathernut07/02-28-07SRV.png

[afischer]

As you can see from my pictures in the REPORTS section, the tornado had the appearance of a wedge and then, within the next lightning flash or two, it had lifted completely up as it passed HWY 169 and entered Colony.

Are you sure the tornado initially touched down west of Colony?

I was maybe 2 miles south of town, looking in every direction... the mesocyclone was so high-based and flat that I thought instead I was seeing some sort of inflow tail stemming from an HP supercell. I couldn't see any signs of rotation when the lightning flashed. I guess it's possible it touched down as I ventured into the town and had my "back turned." That would explain how I somehow got through town without seeing the tornado (especially if it temporarily lifted while skirting the south side of town).

About halfway down the street through Colony, leaves (lots of them) were literally floating in the street a few feet off the ground. Then they began accelerating toward my car as stiff northeast winds picked up. I became alarmed and gunned it out of town, thinking this was inflow into a tornado behind me. In fact it was strong cyclonic flow on the back side of the tornadocyclone. (Just east of Colony I saw the tornado about 1 mile to my east-northeast.) Not my most shining moment as a chaser, but I was convinced I'd fallen well behind the meso when I first ventured into Colony due to the lack of structure.

[fplowman]

Are you sure the tornado initially touched down west of Colony?

I was maybe 2 miles south of town, looking in every direction... the mesocyclone was so high-based and flat that I thought instead I was seeing some sort of inflow tail stemming from an HP supercell. I couldn't see any signs of rotation when the lightning flashed. I guess it's possible it touched down as I ventured into the town and had my "back turned." That would explain how I somehow got through town without seeing the tornado (especially if it lifted while skirting the south side of town).

About halfway down the street through Colony, leaves (lots of them) were literally floating in the street. Then they began accelerating toward my car as stiff northeast winds picked up. I became alarmed and gunned it out of town, thinking this was inflow into a tornado behind me. In fact it was strong cyclonic flow on the back side of the tornadocyclone. (Just east of Colony I saw the tornado about 1 mile to my east-northeast.) Not my most shining moment as a chaser, but I was convinced I'd fallen well behind the meso when I first ventured into Colony due to the lack of structure.

Afischer

Read my account on page 1.. I feel that it did set down - and then possibly reorganize ??????

Only reason for this was the wall and black lowering west of Leroy and then the smell of pine trees in between leroy and colony.. maybe about half way in between... We slowly drove towards colony trying not to enter the hail core if you want to call it that.. As we sped up we would get hail.. slow down.. it would subside.. strange..

Man I cant tell .. I feel like Dirty Harry.. " in all the excitement was it two twisters or only one? Do you feel lucky? lol

[Mike Parker]

I am not 100% sure, no. Like I said, it was nearly impossible form my location to see ground circulation. All I could see was millisecond flashes of what "appeared" to be a rather wide looking tornado that looked to be on the ground. I went back to the exact location that I assumed the tornado would have crossed 169 and I saw no visible damage. I did notice that west of Colony is a rather hilly and treeless terrain. There is nothing there to damage even if it was touching down. I do know it was most definitely not on the ground as it went into Colony. That is plain as day from my video. You can plainly see cars that are traveling on 169 between me and the wall cloud.

Andy, which way did you exit Colony? Was it East? If you were on that blacktop road heading east then you barely escaped the tornado as it touched back down. There is plenty of damage starting about 2 miles east of Colony and just a quarter mile north of the blacktop.

[Michael O'Keeffe]

This is a picture of the apparent wedge, west of Colony. I am about 1-2 miles south of Neosho Falls here. To me it looks more like dust than scud. IMO i don't think that is hail either because that is right where the clear slot is and the hailcore is being illuminated behind the tornado.

http://i84.photobucket.com/albums/k3/wolverines028/2_28_20078_10PM_0001.jpg

[afischer]

I am not 100% sure, no. Like I said, it was nearly impossible form my location to see ground circulation. All I could see was millisecond flashes of what "appeared" to be a rather wide looking tornado that looked to be on the ground. I went back to the exact location that I assumed the tornado would have crossed 169 and I saw no visible damage. I did notice that west of Colony is a rather hilly and treeless terrain. There is nothing there to damage even if it was touching down. I do know it was most definitely not on the ground as it went into Colony. That is plain as day from my video. You can plainly see cars that are traveling on 169 between me and the wall cloud.

Andy, which way did you exit Colony? Was it East? If you were on that blacktop road heading east then you barely escaped the tornado as it touched back down. There is plenty of damage starting about 2 miles east of Colony and just a quarter mile north of the blacktop.

Mike, yeah, I took the main drag (300 St SW or whatever) through Colony and stayed on it... it remains a paved road over to Lone Elm. I encountered that damage along the road a couple miles east of town via two downed powerpoles (one powerline hanging diagonally across the road) and two barbed wire fences stretched across the road. I was delayed about five minutes here.

I wouldn't be surprised if it did touch down SW of Colony (and I somehow missed it), then "skipped" over the southern outskirts of Colony. After it did the powerpole-snapping and I saw it for the first time... it was hardly even showing any rotation... just looked like ominous scud fingers hanging from a high-based flat mesocyclone... so it coulda been "skipping" then, too. Looked better later on (around 715)... like an actual tornado, that is. lol

[Mike Peregrine]

I will say that this particular storm was pretty challenging from a spotter/chaser perspective. The reason for this in my mind amounts to the fact that the meso was very large, and any lightning was occurring in the precip core off to the northeast for the most part, putting it a ways off from the tornado at any given time. Sheet lightning seemed weak to me (especially for the size storm we were working with), and in general the lightning was sporadic. I got like one or two decent freezes from video (hasn't been posted yet), which shows what it was like - since I had that camera trained on it for like 10 minutes. If I hadn't known exactly where I was in relation to the tornado, it would have been really difficult to spot. My guess is that the situation was pretty similar further upstream where you guys initially intercepted. I'm anxious to see EAX's assessments.

[Mike Parker]

There seems to be a theme I am detecting. I have talked to two separate chasers that were basically in Colony as the storm approached. Both said that they could not see anything west of them. One of the chasers (he is a member of this board and can chime in if he wishes) moved a few miles south and could plainly see the meso. The other chaser stayed there and never saw the meso until it literally was on top of them. So, for some reason, if you were looking west form Colony, the view of the storm appears to have been obstructed by something but by moving just a bit south, things became in focus. Just an observation that may or may not be relevant.

[Darin Brunin]

I guess I might as well throw in my opinion........

We got back to highway 169 and were in Colony probably 3-4 minutes before the rotation got there. I totally agree with Andy that when it was on the west side of Colony there was no structure to be seen and we were saying "WTF is going on here" Just as it started to move over Colony a new wall cloud developed and a tightly wrapped funnel maybe 1/4 of the way to the ground formed over the city or just east of it. So in my opinion the storm was cycling for a few minutes before it approched Colony. I haven't looked at radar of it yet so that is just my guess of what happened. We then moved east out of Colony on 350th road and saw the tornado touch down for the first time right on or just a little north of 350th road 1-2 miles east of Colony. If you look it up on Google Maps, it's the gravel road that goes east of out of the north side of Colony.

Now for the description.....I don't think that it really matters what shape the tornado was....A tornado is a tornado and will do equal damage no matter the shape of it is. Before the tornado formed there was definitely a lot of scud underneath the base and we even used the word "scud bomb" when looking at it. Then a definite funnel emerged on the right side on of the wall cloud and that was when we called it a tornado because the other two "vortices" on the left side really looked raggedy and weak as seen in the photo below but still had circulation beneath them. When it first formed it was definitely a multivortex.

http://tornadolive.com/multivortex.jpg

After we were stopped by powerlines down across the road at SW Grant we watched the tornado morph into what I called a barrel kind of stovepipe and then it grew even a little larger from what I can tell as it moved east away from us. It was getting big enough that I could see why someone might call it a wedge but in my honest opinion it seemed like it was changing shapes everytime that there was a flash of lightning to illuminate it so trying to coin it with one term is definitely not the right thing to do.

Whether someone called it violent or not at the time shouldn't have been taken seriously then and shouldn't now because in the heat of the chase it is easy to get over excited as well all know.

Darin

[Scott Olson]

I would have really enjoyed chasing this beast but It wasn't too bad watching it unfold on radar. As it entered Missorui it displayed behavior of a very mature supercell, in some instances forming having a new updraft couplet form to the east in just a single scan. I'm going to try and do a full recap of the first part of the supercell's journey using the saved L2 data and the information you all have provided. I hope to have this together tonight or by tommorow.

[Wesley Luginbyhl]

Here is a picture from west of Colony looking east towards Colony. There are power flashes every couple of seconds at this point and it looks like one in the picture (maybe?). This was about 2 or 3 minutes after the tornado report came out. The funnel on the right i believe is the main event. You can see see the clear slot just to the right, above it.
http://photos-977.ak.facebook.com/ip002/v67/197/119/9609344/n9609344_33219977_2056.jpg (http://ou.facebook.com/photo.php?pid=33219978&id=9609344)

Here is a picture from maybe 10 seconds later. You can see obvious scud filling from the left. Whatever it is, is very low to the ground.
http://photos-980.ak.facebook.com/ip002/v67/197/119/9609344/n9609344_33219980_2941.jpg (http://ou.facebook.com/photo.php?pid=33219981&id=9609344)

That big mass hanging down did not last long, but the multivortex followed about 5 minutes later well east of town.

[Scott Blair]

Darin Brunin wrote:
Now for the description.....I don't think that it really matters what shape the tornado was....A tornado is a tornado and will do equal damage no matter the shape of it is.

ALSO...

Whether someone called it violent or not at the time shouldn't have been taken seriously then and shouldn't now because in the heat of the chase it is easy to get over excited as well all know.

I couldn't disagree more with the above statements. Listen folks, specific/detailed reports of exactly what is occurring with a tornado are critical to the NWS mission to save life and property. If there is any degree in question to what you're observing, then DO NOT jump the gun and label something that isn't...especially if you are reporting something in. I don't care if somewhat is excited or not...calm down...make a GOOD observation...and then call in a QUALITY report. There is NO excuse for saying I was overly excited at the time...oops...sorry about that report. That report has already been implemented into the warning decisions at the local NWS offices. Bad reports for whatever reason bring down the warning process as a whole. For those newer chasers out there, please take the time to carefully examine what you're observing.

Just my two cents from a chaser/radar operator perspective.

SFB

[Dick McGowan]

Darin Brunin wrote:
Now for the description.....I don't think that it really matters what shape the tornado was....A tornado is a tornado and will do equal damage no matter the shape of it is.

ALSO...

Whether someone called it violent or not at the time shouldn't have been taken seriously then and shouldn't now because in the heat of the chase it is easy to get over excited as well all know.

I couldn't disagree more with the above statements. Listen folks, specific/detailed reports of exactly what is occurring with a tornado are critical to the NWS mission to save life and property. If there is any degree in question to what you're observing, then DO NOT jump the gun and label something that isn't...especially if you are reporting something in. I don't care if somewhat is excited or not...calm down...make a GOOD observation...and then call in a QUALITY report. There is NO excuse for saying I was overly excited at the time...oops...sorry about that report. That report has already been implemented into the warning decisions at the local NWS offices. Bad reports for whatever reason bring down the warning process as a whole. For those newer chasers out there, please take the time to carefully examine what you're observing.

Just my two cents from a chaser/radar operator perspective.

SFB

Since when did Mr. Brunin say that he called in a report to "your office." ?

Does it MATTER if it is a wedge or a stovepipe? A tornado is a TORNADO and regardless, people should take cover.

You can't sit here and tell me that Mr. Smith won't take cover for a rope tornado, but will for a wedge. Give me a break.

PS: Darin never reported anything to your office (neither did I), and if you are going to sit here and ridicule chasers for what they OBSERVED, then maybe you can just rely on your spotters next time.

[Mike Peregrine]

Scott O. - it would be great to see that. I've only seen a couple of radar grabs so far that someone had posted in the NOW thread. Also - Wesley's photos reminded me of something else that I feel like may have gone on more than once with that storm, and that is incomplete condensation funnels, or at least debris clouds that were obscurring the base of the tornado at times, which seems to happen a lot at night. It's possible that there were times that multiple funnels were producing enough debris to make multi-vortex indistinguishable from a 'wedge.' It would be good to try and figure out what was going on with the storm during those times. I've even wondered just after the first cycle, if some heavy precip may have been wrapping tightly. Scott's radar might help.

This storm was definitely cyclic, and it seemed to produce tornadoes that lasted for a few minutes, quickly occluded, followed by new tornadogenesis downstream. There appeared to be long periods of time when the storm was 'taking a breath' and regaining its composure, possibly ingesting some of its own outflow for a bit and then going back to tapping into the somewhat marginal moisture available to it. My brother was nowcasting and just as he would think the storm was in a weak cycle, I would see it get its act together again and reorganize (the time lag/discrepancy between radar and ground truth was really apparent). This was really noticeable at one point when the storm moved east of Adrian. The meso became disorganized for a while just east of 71 highway, but about ten minutes later it became noticeably organized again. The lightning picked up and the base really tightened up again. It wasn't long and the meso became obscurred and things calmed down. The third strong cycle that I observed came again north of Urich, where the storm tornadoed again.

[Jeff Snyder]

I've uploaded *.rv3 files from EAX and ICT for some of the time the supercell was churning across se KS. You can access these at http://www.tornadocentral.com/now/Feb28/ ... Check out the EAX folder and file keax_20070301_015312.rv3 , which will show you the BR1 of the supercell as it was immediately north of Linn, KS. Hook-o-rama! Just right-click the file(s) you want, and do "Save As". Then, you can just just drag it into the GR3 window (e.g. open up My Computer, move to the folder in what you saved the files, and drag the file(s) into the GR3 window). For a teaser:

http://www.tornadocentral.com/now/Feb28/0228LinnKSsupercellBR1.png

[Scott Blair]

Dick,

I never suggested anyone in particular on this list called the office I work for. The problem with Darin's statements highlight an underlying problem with an attitude that reaches far past this event. Unfortantley, we did receive numerous calls from similar observations that have been posted on here, which was not the best descriptions for the ongoing event. And I understand Darins statements might have been more directed towards the current thread. With that said...

Is it not obvious why it is important to properly describe a tornado??? Give ME a break! You, as a chaser (if you plan to aid in the warning process), should focus on prodiving the NWS with the most accurate information possible. There is a major difference between a wedge (large tornado) and a rope...both from an impact and warning standpoint. Even the call-to-action statements within the warnings will reflect this. Also, understanding what phase a tornado is in contains helpful information to the radar operator/office to better visulize what's truly occuring.

My posts do not attempt to anger anyone, but simply educate those interested in the importance of accurate information into the NWS. I do not apologize if someone takes this personally and fails to see I'm simply providing insight into the importance of quality contributions to the local NWS offices.

[afischer]

I couldn't disagree more with the above statements. Listen folks, specific/detailed reports of exactly what is occurring with a tornado are critical to the NWS mission to save life and property. If there is any degree in question to what you're observing, then DO NOT jump the gun and label something that isn't...especially if you are reporting something in. I don't care if somewhat is excited or not...calm down...make a GOOD observation...and then call in a QUALITY report. There is NO excuse for saying I was overly excited at the time...oops...sorry about that report. That report has already been implemented into the warning decisions at the local NWS offices. Bad reports for whatever reason bring down the warning process as a whole. For those newer chasers out there, please take the time to carefully examine what you're observing.

Just my two cents from a chaser/radar operator perspective.

SFB

Excellent advice.

I think Darin was more responding to the dissenting views within this thread regarding what the Colony tornado really "was," though... not advocating irresponsible or exaggerated reporting of severe weather to NWSFOs.

[Mike Parker]

Scott, could you give us examples of what kind of reports you were getting? I agree that IF one decides to call a NWS office that the report should be accurate. However, if a chaser calls in and says he or she sees something and that turns out to be inaccurate, IE.. wedge vs rope.. would you prefer not to have the report at all? I am just curious. I don't call in reports so I have never taken the time to figure out what is most helpful for you guys.

[Darin Brunin]

The problem with Darin's statements highlight an underlying problem with an attitude that reaches far past this event. Now for the description.....I don't think that it really matters what shape the tornado was....A tornado is a tornado and will do equal damage no matter the shape of it is.I was referring to the discussion on here. I didn't say that I was overly excited and never called in any reports to the NWS office because I was on the phone with a TV station in Topeka reporting back to them....but I figured that someone probably was when they called in the report or posted it on here and I was simply saying that calling a tornado violent is foolish without seeing damage...especially at night. Whether it or any other tornado is violent should not have any bearing on whether you issue a warning because you obviously know that an EF0 can kill someone. I am not disagreeing with on reporting tornado sightings but that you have to be careful with what you hear and I hope that you wouldn't use someone calling a tornado violent at night in a storm lacking lightning in the warning decision process.

As far as the shape goes...I was talking about people on here being critical about "where is that so called wedge tornado that occured the other night" Whether the people were right or wrong in calling it a wedge tornado does not matter when looking back on the event because people were probably excited that they saw a big tornado and whether it meets one's "wedge classification status" or not, you should ultimately take their word for it because they were there afterall.

[Scott Blair]

Mike,

An excellent question! Obviously in a perfect world, we strive to have every report as accurate as possible. However, there are times when visual observations are extremely difficult to observe. If one encounters such a case, still call into the NWS to report the event...BUT please make it clear there is a certain degree of uncertainty from your viewpoint on what precisely you're observing. From there, the NWS and the observer can piece together whatever clues/information exists. There is no harm for admitting a certain degree of uncertainty from what is being observed...just so long as it's stated and no assumptions are made.

We happily welcome every report we receive and are quite grateful for those that find a little time to pass information along.

SFB

[Mike Peregrine]

EAX has posted their event summary here (http://www.crh.noaa.gov/crnews/display_story.php?wfo=eax&storyid=6417&source=0).

I can't believe how close I actually was to that tornado, just about a half mile now that I'm looking at the map. Good grief - I had no idea.

[Scott Blair]

Darin,

I agree. The difficulty comes when an office receives multiple reports of a large violent tornado, followed by a stream of damage reports. Usually we don't know the scope of the damage. The tough part is when sending an update statement or new warning...the choice must be made do we classify this as "a large damaging tornado?" If it actually isn't, then we have just provided poor information and cried wolf to all our users. Of course, every situation is different and hence why the quality/accuracy of reports aids us in the warning process.

From a side note...I've always been under the impression a wedge tornado is defined by those tornadoes that appear to be at least as WIDE as they are TALL (per SPC). I'd certainly welcome any other insight.

SFB

[Mike Parker]

Holy crap!! All that was left was the basement. They walked away with no physical injuries but I bet they have some emotional issues after that.

[Jeff Snyder]

The pictures of the house removed are quite impressive. From the pictures (which never tell the entire story, such as method by which the walls were anchored, etc), it certainly looks like DoD 9 or 10. The expected winds for both DoDs (for Damage Indicator / DI / 2 -- one- or two-family residences) is in the EF4 range (170 and 200mph, respectively). See page 25 at http://www.wind.ttu.edu/EFScale.pdf .

For those wondering what "engineering quality" constitutes, there is an example on the WDTB presentation at http://www.wdtb.noaa.gov/courses/EF-scale/lesson2/player.html ... In particular, watch "frames" 15-18 (and note how the type of fastening between wall stud and sill plate/foundation strongly affects the "strength" of this part of the frame, with a clip being at least several times more resistant to upward forces than straight nailing). Another example is on 'slides' 40-41 (from the Hallam tornado). In the picture from the recent event, the damage looks worse than the damage seen on slide 41 (which was DoD9, airing towards the lower-bound winds given that the studs were singly, straight-nailed). An EF4 seems like a pretty good guess, depending upon just how well the home was built (possibly EF3 if it was poorly built). I'd at least open the possibility of EF5 if it weren't for the fact that it looks like the front wooden steps on the right of the picture are intact. I'd imagine that winds strong enough to cuase EF5 damage (>200mph) would at least destroy some wood steps.

[Eric D B'Hymer]

I believe i called in an accurate report to ICT from what i observed from my position. I reviewed my tape and i was very calm and accurate as to what i was reporting. I also told the person who answered my position and the probable position of the tornado. The report came out that the tornado was in my position and not where i desribed it to be which i understand happens in stressful times. I have shown my video to others and my report from page one is very accurate, and after talking to other chasers and spotters that were within 3 miles of my position, i have concluded that my report was quite accurate. I have also looked at the damage photos, good thing that the colony area is small and sparsely populated. Had this gone through any city in Allen County, the results would have probably been fatal due to the total lack of a spotter program, guess its a good thing i was home on this date. Im not going to get into this debate on damage, i am not into damage assessment, i am just glad no one was injured and hopefully my report saved lives and thats all i care about.

[Mike Parker]

Look, I totally believe Eric's report to ICT was dead on from what he was seeing. I was one mile north of his location and saw the same images he was seeing. Honestly, if you had seen this (link to pic) (http://i14.photobucket.com/albums/a331/weathernut07/wedgelg.jpg) for a split second of a lightning flash, what would you think it was. It appears as wide as it does tall to me.

Truly, Mike Peregrine is correct in saying that getting a visual on this thing was very difficult. I think Eric did the right thing and if I were in his shoes, I would have done it the exact same way.

In fact, I would like to thank him for calling it in, rather than persecute his description.

[Kiel Ortega]

The pictures of the house removed are quite impressive. From the pictures (which never tell the entire story, such as method by which the walls were anchored, etc), it certainly looks like DoD 9 or 10. The expected winds for both DoDs (for Damage Indicator / DI / 2 -- one- or two-family residences) is in the EF4 range (170 and 200mph, respectively). See page 25 at http://www.wind.ttu.edu/EFScale.pdf .

For those wondering what "engineering quality" constitutes, there is an example on the WDTB presentation at http://www.wdtb.noaa.gov/courses/EF-scale/lesson2/player.html ... In particular, watch "frames" 15-18 (and note how the type of fastening between wall stud and sill plate/foundation strongly affects the "strength" of this part of the frame, with a clip being at least several times more resistant to upward forces than straight nailing). Another example is on 'slides' 40-41 (from the Hallam tornado). In the picture from the recent event, the damage looks worse than the damage seen on slide 41 (which was DI9, airing towards the lower-bound winds given that the studs were singly, straight-nailed). An EF4 seems like a pretty good guess, depending upon just how well the home was built (possibly EF3 if it was poorly built). I'd at least open the possibility of EF5 if it weren't for the fact that it looks like the front wooden steps on the right of the picture are intact. I'd imagine that winds strong enough to cuase EF5 damage (>200mph) would at least destroy some wood steps.

Nicely done Jeff...another thing I would point out are the trees (though it's hard to tell which way we are looking relative to the tornado motion). One pic has a small tree (near the house) that is snapped about 60% up its height. In another pic, a bigger tree has it's trunk snapped to...and most of the other trees are chopped up pretty good. But, there is a utility pole still standing b/w the house and the trees. Looking at the house itself, the sill plates look like they were barely moved (suggesting straight nails IMO). Also, some sill plates are missing as you look around the foundation...which makes me wonder about how well the sill plates were attached to the foundation. I would give this damage pictured here a EF-3.

[Scott Olson]

2/28/07 Radar Analysis, a multimedia presentation:

(http://www.axisofnature.com/1/Default.wmv)DOWNLOAD (http://www.axisofnature.com/1/Default.wmv) - High Quality version (reccomended)
OR
Streaming (http://www.youtube.com/watch?v=C3uyXZIQJm4) (YouTube)

[Alex Lamers]

Any word on what that tornado was rated? It's been nearly a week. Did they have to call in the special survey team?

[Kiel Ortega]

Any word on what that tornado was rated? It's been nearly a week. Did they have to call in the special survey team?

No they didn't call in a special team. I talked with a person in the know around NSSL...the people who surveyed from the EAX office posted a lot of pictures and solicited opinions from some people. I had heard they were set in their rating (and no, I will not say it :)), so I don't know what the delay is. From what I posted earlier, I found out the home (picutred on the EAX site) was pretty well built with bolts in the bottom plate about every 3 feet, toe nailed studs and vertical straps b/w the walls and roof. Also heard that grass was scoured in one area. Still confused by the utility pole though...

[Jeff Snyder]

No they didn't call in a special team. I talked with a person in the know around NSSL...the people who surveyed from the EAX office posted a lot of pictures and solicited opinions from some people. I had heard they were set in their rating (and no, I will not say it :)), so I don't know what the delay is. From what I posted earlier, I found out the home (picutred on the EAX site) was pretty well built with bolts in the bottom plate about every 3 feet, toe nailed studs and vertical straps b/w the walls and roof. Also heard that grass was scoured in one area. Still confused by the utility pole though...

That's interesting. I was under the impression that the QRT is called for all assessments when a violent tornado is suspected to have caused some of the damage. From what you've said and what I've thought (see my previous post on Pg3), it certainly sounds like it was a violent tornado.

[Alex Lamers]

No they didn't call in a special team. I talked with a person in the know around NSSL...the people who surveyed from the EAX office posted a lot of pictures and solicited opinions from some people. I had heard they were set in their rating (and no, I will not say it :)), so I don't know what the delay is. From what I posted earlier, I found out the home (picutred on the EAX site) was pretty well built with bolts in the bottom plate about every 3 feet, toe nailed studs and vertical straps b/w the walls and roof. Also heard that grass was scoured in one area. Still confused by the utility pole though...

Thanks. I can understand why you can't give out the rating. :) It did look pretty solidly built so I was very curious to see what they went with. I'm guessing they are just getting everything thoroughly done before they release the info, which in all honesty is probably a good idea. I guess I can wait another couple days! :D

AJL

[Evan Bookbinder]

OK, now that the release has been made official, I can finally speak. The tornado which tracked across Linn county KS has been rated an EF4.

Because this is the first violent tornado under the new scale, I had my survey results and photos analyzed and discussed at length with the QRT and EF scale experts to make sure everything was indeed correct. With the NSSW in Norman and then the Alabama/Georga tornadoes, tracking everyone down took some time. We apologize for the delay, but I think you all can empathize with the fact that no matter the rating, this poor family lost everything.

Thankfully, he received our warning about 25 minutes in advance and took shelter in his basement. He was most thankful and a good-hearted person I know the entire community will rally behind.

We got video from an off-duty AWC forecaster who was coming up the from the S out of Blue Mound -- it's a biggy. What's amazing is that there's no evidence of the tornado "increasing" in size from touchdown, as one would typically expect. This may be due to the extreme low LCL heightsand incredible shear -- (DPDs were on the order of 1-2F from a nearby weather station with low level SRHs estimated at > 1000!!). It basically goes from a wide funnel with multiple tendrils to a large wedge in very short order.

Evan

[John Peters]

Any news on the path width/length? The tornado appears very large in those video stills. It's a miracle that it managed to essentially remain in open country.

[Verne Carlson]

Hi Evan,
Who was the off-duty NWS employee who shot the footage? I would like to contact them for possible inclusion in the Storms of 2007 DVD. Anyone else who got video from this night please PM me.
thanks,
Verne

[Evan Bookbinder]

Verne,

That person is on this forum -- it's up to him if he wants to get ahold of you. The video dub we got was VHS and extremely grainy -- although more than sufficient for our purposes. If his original is digital, then even I would love to see it!

John,

The path length based on connecting all my GPS survey points was about 24 miles. Greatest width (subjective between damage and video) is between 1/4 and 1/2 mile wide. There was just so "little" to hit, but we should have areal photos shortly which should help determine how much of that wedge was actual tornado.

Evan

[Rich Thompson]

We got video from an off-duty AWC forecaster who was coming up the from the S out of Blue Mound -- it's a biggy. What's amazing is that there's no evidence of the tornado "increasing" in size from touchdown, as one would typically expect. This may be due to the extreme low LCL heightsand incredible shear -- (DPDs were on the order of 1-2F from a nearby weather station with low level SRHs estimated at > 1000!!). It basically goes from a wide funnel with multiple tendrils to a large wedge in very short order.

Evan

Evan,

What did you use to estimate the > 1000 m2/s2 SRH? I've reviewed the SPC mesoanalysis graphics, and I don't see anything larger than 300-500 m2/s2 (which is pretty large) for either 0-1 km or the effective inflow layer. We were using an estimated storm motion from 240-250 degrees at 25-30 kt in our SRH calculations.

Rich T.

[afischer]

For anyone wanting to create a modified sr-hodograph for this event, the wind profiler data may be helpful. For instance, ambient 500m agl winds of 40-50kts were sampled, per Neodesha KS profiler.

http://locust.mmm.ucar.edu/case-selection/dates/20070228.html
http://locust.mmm.ucar.edu/case-selection/dates/20070301.html

[Mike Peregrine]

Doesn't look like anyone has posted the link yet, but the additional page with rating information, vid caps and radar imagery can be found here (http://www.crh.noaa.gov/crnews/display_story.php?wfo=eax&storyid=6482&source=0).

[Alex Lamers]

I figured that this would be rated a violent tornado when I saw the pictures of that one house. Interesting that it is the first EF4. I guess that makes sense but it just seems like since we've been discussing the EF scale for a year or so now that the scale was implemented a long time ago!

No apologies needed either, it's good to have the rating process done thoroughly!

Also, it is pretty miraculous that this large tornado essentially remained in rural, open country. I think we can all be thankful for that.

Finally, I'm a bit shocked that our first EF4 tornado occurred in such a setup. When we set out from the NWC here in Norman to go chase NC OK we weren't anticipating the entire event basically to be restricted north of the KS border. Best instability and moisture by far was over NC OK. Of course by the time we got up there the cu that had been bubbling up had essentially fizzled. I guess we underestimated the northward extent that the warm, moist air mass would push.

KCNU metar trends (SE KS) pretty much tell the story:
KCNU 281952Z AUTO 20016G20KT 10SM CLR 24/M02 A2943
KCNU 282052Z AUTO 21014G22KT 10SM CLR 26/M04 A2939
KCNU 282152Z AUTO 18019KT 10SM CLR 24/03 A2937
KCNU 282252Z AUTO 17019G25KT 10SM CLR 22/11 A2937Winds back to a more southerly direction and the dewpoint rises from 25F at 3 pm to 52F at 5 pm. Next time I will examine the advection of the air masses more closely before heading out! :D

AJL

[Mike Peregrine]

Also, it is pretty miraculous that this large tornado essentially remained in rural, open country. I think we can all be thankful for that.


Amen to that. If this had happened even 20 miles north of where it was, it could have been disasterous. Even if it had been just a couple miles off the track in either direction, it would have been in line for some small towns. Having that intense of a tornado this far north so early in the year is what amazes me the most.

What a crazy storm ... >1000 m2/s2 is insane. Was the storm influencing the local environment somehow? That's a crazy big SRH number.

[Eric D B'Hymer]

Winds back to a more southerly direction and the dewpoint rises from 25F at 3 pm to 52F at 5 pm. Next time I will examine the advection of the air masses more closely before heading out!



Alex, i was truly amazed that this dewpoint shift happened myself, i live in Iola 20 miles north of KCNU and i had read the MD that the SPC had out about 2 0r 3 pm and i was like no way, it staed the dryline would retreat to the west as it was stalled on the KS-MO border in the afternoon. Then about 5 the wind switched from sw to the s -se and it got humid real fast and thats when the elk county storm started.

[Evan Bookbinder]

Evan,

What did you use to estimate the > 1000 m2/s2 SRH? I've reviewed the SPC mesoanalysis graphics, and I don't see anything larger than 300-500 m2/s2 (which is pretty large) for either 0-1 km or the effective inflow layer. We were using an estimated storm motion from 240-250 degrees at 25-30 kt in our SRH calculations.

Rich T.

Rich, I find it a tough number to swallow, and these were given by my SOO who had gone back through the data. I'm not sure how they were calculated, but I do plan on doing an extensive analysis and making sure that correct calculations were being made. I didn't mean to haphazardly throw numbers out there, although 1000 is not unprecedented (measured at the Haviland, KS profiler May 7 2002 when a large wedge passed very close to the site).

I will be in contact with you and Glen once I get some time to analyze the data. I think, as Glen pointed out, the DPDs were more realistically like 4-5F in the inflow region. Calculated Storm motion was IRL, 240 @ 30-35 knots. I guess the key to insane low level SRH calculations would be the sfc wind vector. I noticed that SGF's 04Z sounding has a > 500 SRH with a surface wind of 150/10 (150@10) knots. Some of the mesonet data in the vicinity of this surpercell suggests that the wind vectors immediately south of the FFD boundary were from the E/NE. Now, of course we'll never know the true inflow wind as I'm not aware of any chasers who were in this location, but we've all chased enough storms to know that these winds can be 20-40 knots greater than the ambient flow ahead of strong supercells, which could lead to some insane low level SRHs.

Evan

[Glen Romine]

I'd just add that, and I presume that Rich was thinking along the same lines, that the moisture depth for this event probably was much less than 3 km. Effective helicity therefore is going to use a much shallower layer (more like 0-1 or 0-1.5 km at best if there was some local moisture pooling), and so even with the impressive LLJ strength as noted at SGF at 04 Z, you probably struggle to get much better than 600 SRH, and probably more like 400-500, which is still near the top of the significant tornado range of values.


Glen

[Evan Bookbinder]

Glen,

I certainly couldn't argue for more than 1KM, not only from SGFs sounding 2 hours later, but visual evidence of the supercell base at dusk and other data (RUC) that showed an equally low LFC and dwpt values which really tanked above that shallow moisture surge.

I don't have a sounding analysis program here worthy of John Hart's, but I'd be curious as to what values are achieved with 210@50 kts at 1km, a storm motion of 240@30 kts, and then anti-cyclonically curving the hodograph back to a sfc wind using several different values of between 10 and 40 knots with winds nearly due east. Given the sporadic tree damage laying from NE to SW we encoutered surveying the FFD region of the storm, I wouldn't be surprised to see the near surface winds channeled toward the higher end there.

A few chasers who have been privately conversing with me noted that this supercell had an extremely long and persistent inflow tail extending east of the storm, which not only justifies a mesonet ob that was to the S&E of the supercell, but in my opinion provides a better estimate of the near-surface inflow vector.

It's tough to eyeball from a hodograph, but I wouldn't be surprised to see this in the 600-700 range -- 300, 500, 700 it's MORE than enough.

Rich, our SOO says that she sent all the data down to the WDTB, so you guys should be able to access it from there.

Evan

[afischer]

If this discussion is to continue or if someone is going to try to construct a proxy sr-hodograph for this event, I believe the distinction needs to be made between whether you're constructing an ambient environmental sr-hodograph... or an sr-hodograph that is representative of the inflow sector of the storm (i.e., in really close proximity to it, where storm scale processes can obviously enhance low-level SRH). I'm sure an inflow-sector hodograph could be very interesting (Shamrock after-dark storm of 05/15/03 comes to mind, with ESE inflow winds gusting to near-severe levels)... but personally I think the ambient value would be of more use. I'm not familiar with what would even be a significant value of SRH in a particular level (e.g. 1km) if you're talking strictly inflow sector. (I haven't seen any observed hodographs in a tornadic supercell's inflow sector, or studies doing proxy soundings in a tornadic supercell's inflow sector).

I haven't reviewed the event closely, but my gut feeling is that there was nothing in the ambient environment itself that would favor surface winds backed to anything better than SSE. (As has been noted, the 1km SRH was still likely very favorable for significant tornado potential). IIRC, the synoptic warm front surged up to the KC metro area by afternoon. Pressure falls helped to back the surface flow in the warm sector (within which the storm ultimately tracked, along the northern edge of the low- to perhaps mid-50s Td's) between 21 and 00 UTC, which most certainly helped increase the 1km SRH (along with the strengthening 500-1000m agl flow per profilers). But again, unless we're talking about an inflow-sector hodograph very near the storm, I don't see why you'd wanna use anything more backed at the surface than 150 degrees or so. This corresponds fairly well with what I observed around Blue Mound while looking north (gusty winds generally at my back).

If mesonet obs indicated easterly winds and surface dewpoint depressions near zero immediately south of the FFD, then that'd be fine to use for your low-level hodograph and modified RUC sounding... but again, as long as you make the distinction that it's the inflow sector SRH and inflow sector MLLCLs etc, rather than the ambient SRH/MLLCLs.

My 2 cents.

[Evan Bookbinder]

Ultimately, I think we must realize that there is no "correct" answer and we're simply trying to get empirical proxies for things we simply can't measure yet. Moreover, the supercell updraft (tornado) is ingesting air from several different source regions...ambient, RFD, FFD, all of which are locally enhanced along the storm-scale boundaries produced by these colliding airstreams. I think we're all being ignorant to some degree by assuming that one of these is the greatest contribution to buoyancy/shear. All 3 must "play nice" so to speak to get this perfect balance we're after.

So in reality, I think maybe we're trying to too deeply classify things, where in reality there's a lot more subjectivity then saying "this storm had 528.34 J/kg of CAPE" or "it was 600 SRH, not 700". Rather, I think using rough proxies we can ascertain with some reasonable certainty whether a given environment supports supercells rooted in the boundary layer. If yes, and a supercell develops, how do the contributions from these various airstreams support tornadogenesis? To what extent can we measure/proxy them? Are these some rough values that lend toward weaker/stronger tornado potential? I think Rich Thompson and Jon Davies (just to name two), have made immense progress in this area in the past 3-5 years, and we can only hope that the funding for a Vortex II will ultimately help to answer many of the remaining questions.

More questions than answers I realize, but I'd hate to see us getting too caught up in "it was a surface wind of 152 degrees at 13 knots must have been right because that gives SRH value of XXX which produced the violent tornado". I'm equally guilty of this, when in reality the atmosphere doesn't care what the "value" is, just that the balance of moisture, lift, buoyancy and shear are manifested in such a way to support this "entity" that we're all after.

Some food for thought I guess.

Evan

[Reed Timmer]

I haven't seen much discussion on how INCREDIBLE this storm looked just before sunset. I don't know how this wall cloud did not produce...although some faint dust vorticies can occasionally be seen below the wall cloud/funnel.

I just finished a highlight clip of this event...which is dominated by the pre-sunset action.

http://youtube.com/watch?v=-FI1OYyI4Kg

[Evan Bookbinder]

That's pretty incredible Reed. Nicely done and I appreciate the slowdowns to highlight the lightning illumination of ol' Bertha. Out of curiosity, you guys appear to show absolutely no emotion during your video. What kind of boring chasers are you anyways? :p

In all seriousness, could you contact me privately? We'd like to obtain this video if possible for examples of nighttime spotting.

Evan