Was the Tuscaloosa Tornado an EF5? Examining Aerial Damage Photographs

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Image of the Tuscaloosa tornado as it roars towards the Rosedale community. Seven people were killed in two apartment complexes and a home adjacent to the videographer. (Video by Ever Duarte)

□ The tornado that left a streak of devastation through Tuscaloosa and the suburbs of Birmingham during the 2011 Super Outbreak has become one of the most well-known tornadoes in history. It became, at the time, the costliest single tornado on record, and easily the most photographed tornado to date.

The National Weather Service took particular care in selecting a rating for the Tuscaloosa tornado. There was tremendous public pressure for an EF5 rating, and surveyors spent more than a week analyzing and reanalyzing the damage path. The area of particular interest was the Tuscaloosa suburb of Alberta City, where the most intense damage occurred. There was much disagreement, and one survey team awarded the damage an EF5 rating, but the NWS eventually classified the tornado as a “high-end” EF4.

Many people were surprised at the decision. The tornado most certainly would have received an F5 rating on the old Fujita Scale, but the new Enhanced Fujita scale has different and somewhat more stringent rating standards. It is important to note the differences between the Fujita Scale and the Enhanced Fujita Scale, as the Tuscaloosa tornado likely lies squarely in between the two categories.

Below are aerial damage photographs that follow the tornado’s path of destruction from Tuscaloosa to suburban Birmingham. Particular attention is paid to areas where EF5 damage may have occurred.

Click on each photo to enlarge.

As the tornado entered the heavily urbanized southwest side of Tuscaloosa, it devastated two large apartment complexes and caused seven fatalities. A dozen buildings were leveled at the Rosedale Community (bottom left), and a section of the Charleston Square Apartments (top right) was flattened, hurling two college students to their deaths. Perhaps the most impressive footage of the tornado was captured by Ever Duarte from an apartment immediately out-of-frame at top center.

A high concentration of fatalities occurred in the Cedar Crest neighborhood, where large, well-built homes were completely flattened. Forest Lake (visible to the left) may have provided the tornado a brief respite from ground friction.

Hurricane force inflow winds shattered windows and uprooted trees four blocks away from the EF4 damage swath. The storm’s massive appearance on video was largely due to the low cloud bases typical of supercells in the Deep South. Compared to most violent tornadoes on April 27th, the tornado was quite narrow as it passed through Tuscaloosa – all of the worst damage was confined within a 150-yard wide streak. After exiting town, the tornado widened considerably.

The tornado strengthened as it crossed University Boulevard into the suburb of Alberta City. An apartment complex was completely leveled and a large food store (lower right) was swept completely away. There were multiple fatalities in a home just north of the store. Damage in this area was extreme, and an F5 rating on the Fujita Scale was likely appropriate. On the Enhanced Fujita Scale, damage in this area was borderline (but not clearly) EF5 in intensity.

Wider view of the damage around 25th Street. Large, multi-story buildings were obliterated and grass was partially scoured from the ground. The Tuscaloosa tornado was very fast moving and caused most of its damage in less than five seconds.

Video of the tornado from 2406 University Boulevard. The swath of possible EF5 damage passed less than a block east of this location.

Close aerial view of the devastated school near University Blvd. The grass scouring within the streak of worst damage is consistent with a tornado of EF5 intensity, but the damage to the flattened school was deemed to be of high-end EF4 intensity due to the presence of undamaged light poles just south of the main building. (Image by Tim Marshall)

Close aerial view of the devastated Alberta Elementary School. The grass scouring within the streak of worst damage is indicative of extreme intensity. Upon reviewing the damaged school, Tim Marshall awarded an EF4 rating as he found that there were “no ties between the walls and the foundation” (AMS, 2011). (Image by Tim Marshall)

View of the Tuscaloosa tornado over Alberta City. The tornado was likely near maximum intensity at this time. (BamaUAMS)

The tornado was near peak intensity as it passed over the Chastain Manor Apartments, where two residents died. A survey team headed by the National Science Foundation considered the damage to the newly built apartment complex to be of EF5 intensity (LaDue, Marshall, 2011). Two additional survey teams, however, considered it to be “high-end” EF4 damage. The southern building’s second floor, which was at ground level on the uphill side of the complex, was swept cleanly away to its cement floor. The structural anchorage was to code, but not considered “superior” in quality.

One of the UA survey members standing above the remains of a bathroom in the Chastain Manor Apartments. The plumbing fixtures were ripped from the floor, one of the damage indicators that led this particular team to award an EF5 rating. (Songer, 2011)

Close aerial view of possible EF5 damage to the Chastain Manor Apartments. A small but well-constructed club house, just out of frame at bottom, was also swept completely away. Grass around the complex was damaged, but not completely scoured. Considering the speed and size of the tornado, the damage to the apartments likely occurred in only a few moments by instantaneous gusts in excess of 200mph.

After devastating the Chastain Manor Apartments, the tornado tore through a neighborhood along County Road 45. There were multiple fatalities on Crescent Lane as homes were swept from their foundations.

Boats from a business along Keene Street were turned into large projectiles as the tornado struck homes on 5th Street NE. Two homes at bottom center appear to have been swept completely away. The Enhanced Fujita Scale requires that a home of “superior construction” be swept cleanly away for an EF5 rating to be applied. The homes in this area are typical of most frame homes and therefore not adequate to gauge EF5 intensity. The tornado was expanding as it passed through this area and the core of intense damage widened to over a quarter mile in width.

The home at bottom right was likely the one mentioned in the NWS survey as having been swept completely away near Holt Peterson Drive. The house was obliterated in EF5 fashion, but tree damage nearby was not consistent with winds of EF5 intensity. The tornado was a mile wide as it passed through this area. Due to the mountainous terrain, the damage pattern became complex and erratic. Less than a mile northeast of this area, the tornado destroyed a railroad bridge and hurled a 34 ton steel support-truss 100ft uphill.

After exiting the Tuscaloosa metropolitan area, the tornado plowed through 35 miles of unpopulated forestland. Aerial imagery of tree damage suggests that the tornado maintained EF4+ intensity and widened to over a mile in width. Very few tornadoes maintain peak intensity for more than a few miles, nevertheless for

After exiting the Tuscaloosa metropolitan area, the tornado plowed through 35 miles of unpopulated forestland. Aerial imagery of tree damage suggests that the tornado maintained EF4+ intensity and widened to over a mile in width. The tornado, along with several others in the 2011 Super Outbreak, left one of the largest swaths of violent tornado damage ever documented.

After ripping through miles of sparsely populated forestland, the tornado encountered a coalyard rail depot, overturning all but two of the heavy cars. One car, which weighed 36 tons, was hurled 120 yards (visible at center). Eyewtiness statements suggest the car was thrown in one toss as opposed to being rolled. This is the longest distance a railroad car has ever been move, and possible evidence of EF5 winds, as well as an extremely powerful updraft (Knupp et al., 2012)

The tornado encountered a coalyard rail depot just southwest of Pleasant Grove, overturning all but two of the heavy cars. One car, which weighed 36 tons, was hurled 120 yards (visible at center). Eyewtiness statements suggest the car was thrown in one toss and not rolled (Knupp et al., 2012). This is the longest distance a railroad car has ever been moved by a tornado and possible evidence of EF5 winds. Damage in the suburbs of Birmingham also reached borderline EF5 intensity, particularly in a narrow swath of devastation through Concord.

The Birmingham suburbs of Concord and Pleasant Grove both experienced borderline EF5 damage. Well-constructed homes were swept completely away and groves of large hardwood trees were almost completely debarked.

The Birmingham suburbs of Concord and Pleasant Grove both experienced borderline EF5 damage. Well-constructed homes were ripped from their foundations and large hardwood trees were almost completely debarked.

Had the Tuscaloosa tornado occurred back in the 90’s, it would have achieved an F5 rating. The EF-Scale, however, has stricter guidelines that differ from the Fujita Scale. People often erroneously believe EF5 tornadoes are weaker than F5 tornadoes since the former’s estimated wind range begins at 200mph and the latter commences at 261mph. The wind ranges are simply estimates and cannot be taken at face value. The EF-Scale was developed under the assumption that the Fujita Scale overestimated tornadic wind speeds.

All things considered, the tornado likely falls in an unusual place – above the threshold of an F5 but just below the threshold of an EF5. Damage in Alberta City, however, was more impressive than the worst damage caused by some official EF5s, such as the Greensburg, Kansas, tornado of 2007. One inherent limitation with tornado damage scales is the lack of emphasis on wind duration – a variable which, with the addition of multiple vortices and transient wind features, is nearly impossible to calculate. Considering the small size and fast movement of the Tuscaloosa tornado, it is quite likely the tornado had winds significantly higher than other large and more slow-moving EF5 tornadoes. The four tornadoes that were awarded EF5 ratings during the 2011 Super Outbreak, however, were unusually powerful and caused noticeably more intense damage than the Tuscaloosa event, so an EF4 rating may have seemed most appropriate in context.

Above is one of the few videos taken within close proximity of the tornado in Alberta City. The Chastain Manors Apartment Complex was located only a quarter mile south of the videographer’s home.

38 thoughts on “Was the Tuscaloosa Tornado an EF5? Examining Aerial Damage Photographs

  1. I think it’s clear what happened. When Dr Forbes made his trip to Tuscaloosa, he declared it to have many instances of EF5 damage and would rate it as such. Enter Tim Marshall. Just to show everyone who’s boss, he chose to call it a “high end” EF4. I think his motives were obvious.

  2. Interesting how the home near Holt Peterson Drive was obliterated in EF5 fashion, but tree damage nearby was not of EF5 intensity, yet the Wheatland tornado didn’t debark trees at all, but got an F5 rating. Or did I misread something about how the scales function?

    • The home on Holt Peterson Drive is shown in more detail in Tim Marshal’s article about discriminating EF4 and EF5 damage. Shrubs around the home were left standing seemingly without much damage, and the home was reasonably but not especially well-built.

      The Phil Campbell tornado did not completely debark trees in some places with EF5 damage. Yet the overall vegetation damage was extreme and likely indicative of EF5 winds. I once thought it had something to do with the wind duration – that tornadoes that only lasted a few seconds did not have enough time to rip all the bark off trees, but the Smithville tornado of 2011 caused some of the most extreme debarking ever photographed and it had a very narrow, fast-moving core.

      It could be related to the tree species, particularly when comparing two tornadoes that touched down in different regions like the Tuscaloosa and Wheatland events. But overall it remains a mystery.

      • I guess good ole Tim has never heard of a multi-vortex tornado. You know, the kind that can cause EF-5 damage while something next door is left untouched. I think Marshall stepped in after the whole web-connected world had already declared it an EF-5 and squeaked, “Naw it ain’t. It’s just a high end EF-4 cause I said so. I don’t keer what dummies like that ancient Greg Fords says.” Marshall….I wonder if his uncle got him the job. lol

  3. So, Rainsville was awarded an EF5 rating based on the damage at that one home, correct? Because the vegetation hardly showed any traces of being affected at all. Is it possible that forward speed could contribute to damage in some ways (with Smithville, the insane forward speed of 70mph+ would probably create a sledgehammer effect, for lack of a better phrase)?

    • Rainsville was awarded an EF5 rating for more than just 1608 Lingerfelt Road, but that home may have been the primary reason. Other large, well-built homes were swept away on the same street, which the tornado sort of followed for half a mile. There was also pavement and sidewalk scouring farther north, and some streaks of vegetation scouring. The Rainsville damage path was very different than the Tuscaloosa tornado – much more erratic and likely the result of sub vortices.

      I did a post specifically on the Rainsville tornado, I’m not sure if you’ve seen it yet.

      And as for the sledge hammer effect, I do believe that can lead to some of the worst damage in most violent tornadoes. Even the huge Joplin tornado was broken up by small, intense vortices – as can be heard in the Fastrip video.

    • Well I have read from Grazulis that the winds on the right side of a tornado essentially have the tornado’s forward speed added to the rotational speed. It’s the same reason the right eye wall is usually the worst part of a hurricane.

  4. I would love to see more analysis or comparing of EF4 Tuscaloosa to EF5 Greensburg… I have to admit, for a huge, slow-moving tornado I thought that while the Greensburg damage was horrible, it isn’t as bad as some of this, and this happened in literally 5-10 seconds as opposed to a couple of minutes. As slow as Greensburg moved and for it’s size I would have expected to see more Jarrell-type damage.

    • I believe the Tuscaloosa tornado, as well as the Ringgold, Arab and Shoal Creek events, were more powerful than Greensburg and a host of other official F5 tornadoes – examples being the ’98 Birmingham tornado and the ’70 Lubbock storm.

  5. So perhaps a low-end EF5 rating might be appropriate?
    I noticed that the wind estimates for the official EF5 tornadoes in this outbreak were not much over the EF5 threshold in the range of 205-210 mph but your analysis seems to indicate that they were substantially stronger. Also, with the mention of tree damage not being consistent with EF5 winds, wouldn’t that not be as applicable in this case since this tornado was multivortex?

    • My article leaves it on the fence. But I’d probably side with a low-end EF5 rating.

      The wind speed estimates for EF5 tornadoes should be taken with a grain of salt. I imagine that no matter how intense a storm is, it will be surveyed as having been either 200, 205 or 210mph. The highest they seem to go is “210mph+.”

      I believe that instantaneous gusts in EF5 tornadoes are generally in the range of 240 to 320mph, but many (not all) researchers would disagree with me. Comparing damage caused by straight-line winds known to have reached 200mph for long durations (Hurricane Andrew) and the damage caused by tornadic winds lasting only seconds makes me feel very confident in my belief. I’ll avoid explaining this more thoroughly now as it would take paragraphs.

      I believe the Tuscaloosa tornado had an inner core in Alberta City with winds around or above 250mph. That’s purely speculation, but I have my whole life’s research as the foundation of my beliefs. The Smithville and Phil Campbell tornadoes would have had even higher winds.

      As for the tree damage, that was only in reference to that area near Holt Peterson Drive. Large trees were almost completely debarked/de-branched in Alberta City and Concord, which is indicative of probable EF5 intensity.

      • I’d be curious to learn more on this eventually. I recall that thing on hurricanes with similar winds in a discussion involving possible underestimates of winds in the Enhanced Fujita Scale. This actually reminded me of something I found mentioned by Grazulis, but nowhere else, that the vertical component of tornadic winds makes them more damaging than simple horizontal winds at similar speeds. Is this true?

      • Yes, vertical winds are much more likely to cause damage than horizontal winds for two reasons:

        1. Structures as well as things in the natural world (trees) are made with some awareness of high winds as they are quite common in every corner of the world. Strong vertical winds are much more rare (pretty much only happening in tornadoes) and defy gravity, which is the driving force holding most buildings together. Vertical winds, therefore, much more easily cause structures to fail as they act on areas not normally stressed during straight-line winds.

        2. Vertical winds lift debris into the air and can carry it for some distance, unlike horizontal winds. The pieces of debris become battering rams that cause more structures to fail, thereby creating even more airborne debris. Vertical winds can also lift and drop things multiple times, such as cars, causing them to slowly granulate.

        The irregular and rapidly fluctuating movement of air in tornadoes also increases opposing stresses on buildings and thereby increases the chance of structural failure.

        Most EF5 tornadoes have sub-vortices or one central vortex (eg. Smithville) that likely obliterate homes in one big explosion, much like a nuclear shockwave mowing down a row of houses all at once. The Smithville tornado’s swath of EF5 damage was often only 30 yards wide, and the tornado moved at 70mph, so the EF5 winds would have lasted only one second.

  6. The EF scale, as well as the old Fujita scale were/are extremely flawed. You correctly point out the effect of duration of winds on damage, but one other thing to consider is the amount of debris. A tornado that has more debris to work with, and has longer duration, can do more damage with lower speed winds than a tornado that hits a farm house in the country without much debris, moving much quicker (thus less duration on the structure) with higher wind speeds. I would like to see tornadoes rated totally different, but that would take up a page and a half describing it, but let’s just say that it wouldn’t be much different than how you’d rate a figure skater, or other athlete who gets awarded points for certain aspects of their performance, and then get an overall rating.

    • Forget the flaws inherent in measuring damage and wind speed, what I would like to know is why we only assign a single rating to each tornado. For example, the Moore 2013 tornado was on the ground for 17 miles and yet only one small section of town near the Briarwood School sustained EF5 damage. For all intents and purposes, the Moore 2013 tornado was a solid EF4 with only a short burst of EF5 intensity. Yet, because of that short burst, the entire tornado event is now rated as an EF5. Tornadoes shouldn’t be rated using the “F” or “EF” scales because their winds and intensities are not consistent over the course of the storm.

      • It makes sense to rate tornadoes on the single most intense instance of damage, much like all other natural disasters. An earthquake with a magnitude of 9.0 on the MM scale should be rated a 9 even if more than 95% of all areas affected by the earthquake experienced ground motion consistent with a weaker event. A hurricane with winds of 180mph (always the peak winds are in a small area) should not be given a lesser rating because most areas experienced significantly weaker winds. Same with tornadoes – all EF5 tornadoes cause EF5 damage in a relatively small area – but that constitutes the full damage potential of the storm.

        Eric – the amount of debris is important but difficult to standardize (like everything else) because increased debris and increased ground friction from tightly packed homes and trees can decrease the surface winds as well.

      • I draw upon my experience in sandblasting. I can take the exact same piece of painted steel and run my gun across it with varying factors, but at the exact same pressure, and get different results. If I am about out of blasting media, it only takes a little paint off, even through there’s the same amount of air – maybe even more – coming out of my gun. If I run my gun across the steel quickly, it doesn’t do as well of a job as it would if I went across it slower. If I go too slow, it can actually start to scour and pit the steel – depending on hardness.

        That’s all using the exact same pressure. When I see tornado damage, I look at it like that sandblaster. I think of the amount of debris in the tornado smashing against other stuff, and I look at the amount of time that the tornadic winds impacted the area. It appears to me that the big difference between Moore and Tuscaloosa was the speed at which the tornado moved across the ground, thus limiting the exposure to the most violent winds in the Tuscaloosa tornado. Both had sufficient debris to draw from, and both had sufficient wind speed and strength in the first place.

        If you look at the guess-timated wind speeds of the Tuscaloosa tornado vs. the Moore tornado – there isn’t much difference. Just a few MP/H makes the difference in this case between an EF-4 and an EF-5 rating. The Moore tornado will go into the record books while the Tuscaloosa tornado will get lost in the shuffle. There are plenty of lists of EF-5 (F5) tornadoes, but I haven’t seen a list of EF-4 tornadoes done in the same manner. Yet – the Tuscaloosa tornado had more aspects of it that were extraordinary than the Moore tornado. The Tuscaloosa tornado formed when many other tornadoes were sapping the atmosphere. The Tuscaloosa tornado took more lives, and was on the ground for nearly 70 miles! Not that I guess it matters, but on tape, the Tuscaloosa tornado was visually more impressive with it’s extra vortices and unlike the Moore tornado, I saw huge debris lofted in the air with the Tuscaloosa tornado. Considering that the Tuscaloosa tornado was booking right along, it’s amazing the damage it did. If had moved as slow as the Joplin or Moore tornado, I think it would have easily been rated EF-5, however, one other thing bothers me.

        If you don’t have a structure hit that allows for an EF-5 rating, then you can’t get an EF-5 rating. That’s the trouble with the Tuscaloosa tornado, they didn’t have a structure with “exceptional” construction get hit with the direct winds. The apartments were swept clean, but they said it wasn’t “exceptional” construction. So in the end, it’s just a guessing game. That is unless you have a Doppler on Wheels and measure the wind speed, in which case you can get an EF-5 rating without having to have the damage – even though the EF rating system specifically says it is based upon the damage. It’s a mess.

  7. Funny how some of you mention Tim Marshall. He and Gary Woodall are responsible for rating the Westminster, Texas tornado a high-end F3. Why? Because there were objects directly in the damage path near the F4 damage that were untouched or barely moved. I think Tim Marshall has done some very good things but I feel like this survey was nothing but a crock. Here is a write up by Gary Woodall which is also a crock as well. It is the very first post. http://www.stormtrack.org/forum/showthread.php?9188-Many-Factors-In-Rating-A-Tornado. Yet, Tim Marshall supported the EF5 rating for the Greensburg tornado and this recent El Reno tornado which IMO didn’t do anything in comparison to the Westminster tornado.

    • Tim Marshall is one of the most experienced damage surveyors out there. He is also very conservative, for the most part, and relies heavily on structural anchorage indicators when conducting his surveys. This can be an effective way to downgrade highly overrated tornadoes (La Plata tornado of ’02).

      It is undeniable, however, that there is quite a bit of inconsistency in the rating standards. I haven’t seen his first-hand observations of the El Reno tornado anywhere, but I would completely disagree with him if he felt it deserved an EF5 rating.

      Also, if other surveyors overlook ground scouring and empty foundations due to there being several undamaged objects on a property (car that wasn’t moved) – well, that completely ignores the whole concept of suction vortices and the erratic nature of tornadic damage in general.

  8. I think it is ok to be conservative but that survey was completely a crock. I would have gave the Westminster tornado an F4 rating without a second thought. An F4 rating may even somewhat conservative based on the damage it produced. You said you would have went with an F5 rating. I do agree with Tim on rating the Tuscaloosa a high-end EF4 but I do see some of your arguments for an EF5 rating based on some of those damage photos. Yes, the La Plata, Maryland tornado on April 28, 2002 was a big mistake when F5 damage was only proven to be F2 damage. This another thing I agree with Tim on is to check surrounding areas as well as the home damage.

    • I basically agree with the high-end EF4 rating for the Tuscaloosa tornado – particularly in the context of the outbreak as there were several even more intense tornadoes the same day. But had that tornado occurred on its own, without the context provided by Phil Campbell and Smithville, it would have received an EF5 rating (certainly looked worse than Greensburg). The tornado is sometimes overlooked due to it not receiving a top rating, but it caused EF4/borderline EF5 damage from Tuscaloosa all the way to the Birmingham suburbs 60 miles to the northeast. It was an incredible meteorological phenomena, as were perhaps a dozen other tornadoes that day.

      • Tornadoes aren’t supposed to be rated in comparison to one another. 100 years from now, the Tuscaloosa tornado will be largely overlooked because of its rating. They just don’t make many lists of EF-4 tornadoes. The Tuscaloosa tornado actually was more intense than many other EF-5 tornadoes, especially when you consider the amount of damage it did moving across the earth at the speed it did. The damage it did was done in a shorter amount of time than say, the Joplin tornado, which moved very slowly across the ground. The Tuscaloosa tornado was on the ground for many, many miles compared to more recent EF-5 tornadoes. When you also consider that the Tuscaloosa tornado had to fight for energy from all those other tornadoes in a sense, it makes it even more amazing. It’s not like it was a lone supercell that had all the energy to itself. What killed the EF-5 rating was that they said the construction wasn’t superior. This is just a wild assumption, but I would bet if Josh Wurman had his DOW truck there, it might have been rated higher. But then, I’d be complaining about another “Doppler indicated” EF-5………..I just wish they’d overhaul how they rate tornadoes.

      • Eric – I agree with a lot of what you said. I don’t think the Tuscaloosa tornado will be overlooked, however, due to the extent of the damage, the number of fatalities and the dozens of incredible films taken of the storm. The 1896 East St. Louis tornado, the 1936 Gainesville tornado and the 1979 Wichita Falls tornado remain well-known despite receiving F4 ratings (although the previous two were well-known for years before they were categorized).

        Additionally, there were more than a dozen other tornadoes that were as violent as the Tuscaloosa tornado on 4/27. I wonder what the films would have looked like had the Phil Campbell, Smithville, Philadelphia, Trenton, Rainsville, Shoal Creek, Uniontown etc. tornadoes passed through Tuscaloosa.

  9. I just came across this. Fascinating. If this isn’t reason enough to scrap, or at least re-think the current tornado rating system, then I don’t know what is. Even the NWS says it’s subjective when they rate these things. I can understand that, but there are some things which aren’t subjective, like the width of the tornado, tornado track length, time of day, and many other things that make a tornado significant. I mean really – a high end EF-4 and a low end EF-5 are only a couple of MPH different in wind speed, but a world apart in how they are viewed. It’s time for something new.

    http://www.weather.com/news/tornado-central/new-engineering-study-finds-no-ef5-damage-joplin-20130610

    And I still say the Tuscaloosa tornado was more impressive than many other EF-5’s that I’ve seen footage of. I would agree that the tornadoes that happened on 4/27/2011 were some of the most impressive I’ve ever seen footage of. Truly awe inspiring storms happened that day.

  10. I do agree with you Eric that the Tuscaloosa tornado was probably more violent than the Greensburg tornado. When the Greensburg tornado was rated an EF5 I was quite shocked. The Tuscaloosa tornado was also almost as wide as the Greensburg tornado though that doesn’t mean anything about intensity. Most of the structures in Greensburg were frail but it only takes one instance of EF5 damage for the tornado to be rated EF5. The Tuscaloosa tornado aerial view damage IMHO looks more impressive than the Greensburg tornado aerial view damage. The Tuscaloosa tornado also did more impressive ground scouring and more complete tree debarking than the Greensburg tornado. Like Max said in one post that he believes intense ground scouring as well as extreme tree debarking should be just as much considered as building damage. I completely agree with that.

  11. I think because of the deaths & the very high-profile of the Tuscaloosa tornado, similar to the 1979 Witchita Falls Torndao, will not get lost in the history books but live on mainly because of their intense damage and both were very high-end EF-4 storms that were right on the brink of EF-5 status. Tom Grazulis in “Significant Tornadoes” stated that in spite of a lot of opportunity, the 79 Witchita Falls tornado did no visible F5 damage. Not sure about that, as I am not very familiar with that storm, but it sure was close to F5 in my opinion.

    I think the Tuscaloosa tornado similarly was very very high end EF-4, and I feel more confident in saying it probably did reach EF-5 strength. The Tuscaloosa tornado reminds me a lot of the 1991 Andvover Kansas tornado in terms of appearance. The motion was tremendous & I would bet the surface winds did reach over 200 mph at points. I think of all the recent high profile tornadoes, Tuscaloosa is under-rated and should have been given EF-5 even if just based on the ground scouring & tree-debarking.

    • From all the imagery I have seen, including the entire aerial damage survey, the Wichita Falls tornado was a low-end F4 tornado. Very few homes were completely leveled and none were swept away, partially or completely. The majority of the damage in the core of the storm was F3, with scattered instances of F4 damage.

      This seems particularly true since the tornado hit more than a thousand homes yet caused only five deaths in residential structures. The Tuscaloosa tornado, which was equally as visible and preceded by the same period of warning, caused 30+ deaths in homes in Tuscaloosa and caused significantly more intense damage in 1/10th the time.

      • I’m curious about that, especially after the evacuation controversy of the El Reno tornado. I know 25 of the deaths from the Wichita Falls tornado were in vehicles an you say five were in residential structures, so what of the 12 remaining direct fatalities?

      • I’m not sure where the other 12 deaths were, but some were in apartment buildings (Tom Grazulis said in Significant Tornadoes that only five deaths occurred in homes) and the others must have been in businesses or out in the open.

  12. To one of your older posts on the Smithville tornado on 4/27/11 moving at 70mph and doing EF5 damage over a 30yd swath. Could it be possible for a tornado to be only 25-50yds wide and move along at 80-90mph and still do EF5 damage? The idea of that would blow my mind because that tornado would probably be packing winds well over 300mph.

    • It’s definitely possible. The 2011 Philadelphia tornado was moving around 55mph when it left a streak of extreme ground scouring (comparable to the dimensions of the storm’s EF5 potential) only 20 yards wide.

      It would be rather difficult to have an EF5 tornado move in excess of 80mph, however.

  13. Just out of curiosity, have you looked much into the Ringgold, GA EF4 of April 27, 2011? I wasn’t able to visit the area after the tornado, even though I lived less than an hour away, but just based on one photo, I was a little surprised it wasn’t given a higher rating. Now, obviously I wasn’t there and have no way of determining construction quality, but it appears that not only were foundations swept clean, there was a bit of ground scouring and concrete pulled from the ground.

    The damage certainly appears more significant than other tornadoes that have received an EF5 rating (Greensburg, KS comes to mind), but at the same time, damage doesn’t appear quite as intense as the likes of Joplin, Moore, Smithville, etc.

    What is your opinion?
    Here’s that photo: http://www.srh.noaa.gov/images/ffc/catoosa088.JPG

    • The Ringgold tornado, much like the Shoal Creek, Cordova and Uniontown tornadoes on the same date, were given EF4 ratings but definitely deserving of an F5 rating on the original scale. The NWS only awarded the damage in Cherokee Valley (the area depicted in the image you linked where 7 fatalities occurred) an EF4 rating with winds of 175mph – it was across the border in Tennessee where they considered the damage to be “high-end” EF4.

      Considering the fast forward movement of all the high-end EF4 events on 4/27 and the largely rural nature of their paths, it is likely all of them were capable of causing EF5 damage. I believe at least 7 or 8 tornadoes were capable of causing EF5 damage during the outbreak.

  14. I was in Tuscaloosa that day, I watched the tornado as it tore through 15th & McFarland. The damage it did, despite how fast it was moving, was nothing short of extraordinary. Despite it (unjustly) being rated a high-end EF4, the Tuscaloosa/Birmingham Tornado of April 27, 2011, will not soon be forgotten. This is true for many reasons, but the three main ones are: 1) It killed 64 people 2) It was on the ground for 70-80 miles 3) It is without a doubt the most photographed tornado in history up to this point.

    • I agree with you to a large extent, but I am also happy the EF-Scale is as stringent as it is. With the new rating system, you know with certainty that the top-rated tornadoes are the worst of the worst. I don’t believe a high-end EF4 rating should be disregarded – it’s just about as intense as they come and does nothing to lessen the violence of the storm.

      The fact that the Tuscaloosa tornado caused a massive swath of borderline EF5 damage for 40+ miles is almost unprecedented. As I say in the article, the storm would certainly have received an F5 rating 15 years ago.

  15. Causes ef5 damage to houses and buildings but nt to some trees gets ef4 rating what a joke, damage is damage regardless if its superior construction or doesnt have hurricane clips/tips, the clips wil get torn out anyway

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