Australian Severe Weather Forum

Also on the map, you can note the tornado track curling back to the left during its weakening and final demise, indicative of the mesocyclone occlusion (Also obvious on May 12, 2004 Jimmy - gosh I feel like I am liivng in the past after looking at tomorrow's convective outlook haha). Also, note how the 2nd tornado track assumes more of a path towards the right while growing very wide, possibly reflecting a further right deviation in the track of the mesocyclone (right move) as it became more and more intense and the vertical pressure pertubation was enhanced. No doubt, the mesocyclone was exceptionally intense during this second tornado.

My meteorologist chaser friend who lives in Oklahoma said to me that this tornado was the most awe inspiring yet most shocking thing he had seen in 6 years of chasing tornadoes.  He had never, ever seen anything so ruthless - even from the Moore OK outbreak - the meso and speed of rotation was just unearthly.  These events apparently coincide with the La Ninya every 10 years or so with uncanny regularity.  Almost all of the outbreaks have had similar weather patterns and just as many supercells spawning multiple tornadoes.  Truly why we are so interested in severe weather.  So many questions and not enough answers from Mother Nature!

Mike

Here's a photo of the Jarrell tornado just prior to it absolutely destroying the Double Creek housing sub-division near Jarrell  http://www.nationalgeographic.com/ngm/9807/popup7.html

Love the shot, David.  I've done some research on the thing but never really saw a decent photo of it.  I have a fellow workmate from western Texas.  We were talking about tornadoes and he mentioned the Jarrell tornado.  He was living close to the town during that time.  His recollections of seeing the thing had a fairly negative impact on him psychologically.  He's seen his factory wall peeled off like a sardine can from an F2 and seeing the Jarrell tornado still has an affect on him. He steers clear of any large hailstone producing supercells because he's fully aware that there may be a tornado around at any time.

I think every one including the meteorologists at the NWS are grateful also to the chasers that film and give reports - it's this kind of gratitude that makes what we do even more important to the whole spectrum of storm observation.

Mike

Not my implication Jimmy, what I was meaning was that the second larger wedge was quite likely stronger than the first, however fortunately it did not encounter other towns before it weakened(and another tornado formed, from the look of it its cyclic mesocyclone formation).

The damage swathes of these two tornadoes are immense and amazing, If indeed the first funnel lifted and moved to amalgamate with the second, It is indeed likely that the second tornado was far more powerful than the first.

I guess this all comes back to the respect for severe weather: really this is a terribly frightening situation, incredibly powerful tornadoes moving through towns in the dark, and we as chasers must understand these dangers, and use the images and knowledge we find to help better protect those in the line of danger. Really seeing images such as insane tornado chase videos are all very well, but it misleads the public into believing that they are safe, only to have an event such as Greensburg come along.

Maybe a poorly constructed train of thought, but it gets what i mean across: I blame sleep deprivation due to assignments.

Such good posts.  Sometimes we get complacent about severe weather and as most of us do at times when there's not much intense events happening here or abroad.  When they do happen it really gets the minds clicking over and reflecting back on past events and comparing them.

It proves beyond a doubt that these significant storms are just so complex and not always 'text book' after all.  Sure they have all the characteristics etc, but as they have proved these supercells are a scientists/meteorologists dream when they happen.  So much information gathered from start to finish and added to that the storm reports from chasers doing the right thing and takng notes of specific things about the tornadoes, rotation, structure and the like.

Fortunately technology makes it easier, but there's nothing like the human element to document footage so that the experts can review and enhance everyone's knowledge.

Who knows, they might even reclassify these 'rare' supercells to another level because of the information.  Instead of your classic, LP and HP they might even prefix it something else!

Never ceases to amaze me that even the experts say that tornadoes are 'rare' with supercells - which is true to some extent as not all produce them - but having over 200+ in most seasons makes you wonder if they're not that rare at all!

Mike

Just to add to Mike's final point there are actually over 1600 tornadoes in the United states each year(reported not sure if all confirmed, particularly for F0s damage assessment sometimes not done).

Yes sorry, John.  I meant 'localised' tornadoes in one particular area.  I understand there's that many just about every year.  My train of thought was on the spate of current events.  My fault!

Mike

Hi,

Just in connection with this discussion, I have pictures of Greesnburg taken during our brief survey at the following link:

http://www.australiasevereweather.com/forum/index.php?topic=443.msg3367#msg3367

Regards,

Jimmy Deguara

Hi John, just in relation to your comment about possible asphalt ripped up - what draws you to that possibility?  Is it just the darkened colouration in the image at that location?  I must say I spent 2hrs slowly driving most of the streets in Greensburg (yes I was Jimmy's chaffeur for the day) and saw no asphalt damage.  Just curious to know if you have heard more?

Hey all,

Well done on the great photos for Greensburg and other Tornadoes.  I was also in USA chasing from May 12th until May 19th, unfortunately it was the week where not many storms formed, let alone Tornadoes.

One of our drivers John took these amazing photos the week after our tour,
http://www.nc911.com/Misc-Photos/storm_chasing_2007_greenburg,ks.htm, one of their guides was a TV Media Reporter, they were allowed into Greensburg for photos.  What a devastating site to see, to see these photos, really shows the enormous power a EF4 or EF5 does have.  From the people I have talked to in relation to this, I do believe its a EF5.  During our chase, saw many towns affected by many other smaller EF3 Tornadoes, even these caused magnificent damage to structures. 

Greensburg, nothing left to salvage.   http://www.kansas.com/626/  Here are some other photos and reports of Greensburg. 

I look forward to seeing Greensburg rebuilt in the near future. 

Thanks
David

Certainly some thought provoking images David.  The raccoon also got my attention!  The great thing about towns like these after major disasters is that they pull together and become even stronger community wise.  Adversity brings out the best in people, especially terrible destruction such as what they encountered.

It will be most interesting to read all the conference/data reports of this event in the months ahead that the NWS, NOAA and experts alike will be compiling.  EF5's are rare and systems like these are rarer. 

I for one will be enthralled by the results and reports when they come out.  thanks for posting the pics, certainly gives a scope to the damage.

Mike 

Hi David Carroll,


Although I respect your point of view, the statement above if I understand it correctly seems almost contradictory. Also please tell us who you talked to about this that made you arrive at this conculsion. Further, you supply images from the media person - which of these perhaps convince you of EF-5 damage?

The EF-5 rating was derived using 3 points of damage within the town. One of these points that still remained was also used by another experienced assessor of damage and this person only sees EF-4 damage from the same assessment. For each point that makes me suggest an EF-5 damage factor, I saw other adjacent damage that makes me rethink lower.

Another thought crossed my mind: could the massive amount of debri carried with the tornado being so large have created 'impact' of incredible damage suggestive of higher damage usually associated with EF-5 when perhaps there may have been EF-4 damage/wind scale?

Getting back to the damage of power poles - most were leaning over but not snapped - even within the town. In the tornado that hit White Deer 29th May 2001, all power poles were snapped bar 1. Of course one can correctly argue the strength of the poles but really would not an EF-5 rated tornado have snapped power poles?

I guess I am not an expert but the damage simply did not add to what I had percieved to be EF-5 rating from descriptions such as those in May 3 1999 and Jarrell, Texas in 1997. What David Croan may be saying that there may have been multivorticies that could have created regions of locally EF-5 'maximum rating' (please correct me of I am wrong in my assumption David).

Regardless of the arguments in this debate, the damage is of mass scale I personally had not observed.

Regards,

Jimmy Deguara

I think re the damage is something no-one can strike out as cut and dry.  There are so many factors that scientists and meteorologists do not not know about wind factors in and around these storms simply because assessing damage from tornadoes has not been proven as 'a matter of fact' - it's all theoretical based on wind, debris, structures and the like.  Smaller EF2 tornadoes have been 'assessed' as having EF4 damage simply because of the structures it has hit in its path and likewise EF4 tornadoes have done damage similar to lower rated tornadoes.

I think David was just expressing the view that from what he's seen and likewise yourself Jimmy, that we're not experts and even the experts rated it as high EF4 or low EF5 (if there is such a thing!).

I did not read his comments as contradictory at all - he mentioned either EF4 or 5, that's not contradictory, that's a viewpoint of what he has seen personally. 

It gets back to the same question of relevance, is it EF4 or 5 damage - nobody knows, that's why the scale is set the way it is, it covers a range between these two.  You answered his comment when you mentioned the amount of debris carried by the tornado may have caused EF5 damage - that may well be the case - if the tornado was on the ground for so long who knows what carnage was arond the vortex area - it would be agreeable to say that the more debris in the area most likely would have caused considerably more damage.

You could ask all the residents of Greensburg what they thought and you'd get mixed answers.  Truth is we'll have to wait and see what the reports say on the event, but it's important to understand that just because residents say it was EF5 or other experts say EF5 or EF4 is irrelevant so far because no-one has the answer.

Mike

Mike,

Rather than get off topic, read carefully what I have suggested as being 'almost' contradictory and don't assume what comments I am referring in his statement:


Further, Mike I think you will find that scientists have developed this lastest Enhanced Fujita Scale it being far more thorough. Mike in your generalised assessment of my post, you incorrectly quoted what I was alerting to. So perhaps if I was not clear, I will perhaps elaborate on my question: is it possible that the amount of debri carried around may have caused EF-5 damage despite perhaps the wind strengths causing EF-4 damage?

I await comments from David...

Regards,

Jimmy Deguara