Just listened to this, couple thoughts. Maybe lowering the EF5 threshold to 200 or 190 would fix part of the problem, but that only solves one of the two heads of this monster. The other problem of the assigned wind speeds being 50-100 mph low is still present, and probably gets exacerbated by this change.
In my opinion there's three problems that are intermixed in various measures in dicussions around the EF scale:
1: The theoretical threshold of what should constitute a '5', was changed for no apparent reason other than personal feelings, meaning all else being equal it's harder to get EF-5. I think people sometimes don't grasp this one very well. But even when they do it quite reasonably frustrates them, because there's no good basis for it. At all. And it leads to absurd situations - as Lyza's paper points out, possibly none of the EF-5 rated tornadoes are ratable as such on their structure damage alone.
2: The windspeed estimates for a given level of damage may be too low. To me this is a bit seperate from 1 and 3, in that it's about much more about the fundamentals of damage for a given windspeed. Whereas most arguments arise from damage allegedly being different in intensity to its appearance on its face. This point also has the minefield of the fact structure failure probably occurs across a range of windspeeds, rather than in one discrete 5 mph increment.
3: Bias in how the ratings are done, with a tendency towards nitpicking any given damage indicator towards a lower windspeed due to alleged issues in construction or other excuses, whilst ignoring features that may indicate a higher windspeed. I note that the original EF-scale paper is rather scant in its definitions of what 'well constructed' means, and while NWS personnel will have their own training material that presumably provides more, it's not much good to anyone who can't access it. Furthermore there's clearly plenty of room for personal interpretaton as seen by inconsistencies between offices.
I'd say the last reason is the major cause for contention. We sometimes have tornadoes that would have been rated as violent without a second thought before now being EF-3. Even if it's 'correct' (disputable) it's not consistent with prior ratings. If people see a structure rated 'all walls down' when it's been entirely swept away, or see WFOs rate something outside the prescribed windspeed ranges, it's no surprise they object. The last tornado to receive the 200 MPH 'expected' windspeed was Rochelle - a decade ago. Despite many instances of houses being swept away since then, apparently none was well constructed enough to get the
expected value.
While you can make the argument that eveyone's home are poorly built, that rather ignores the original intent of the scale (to make an indicative estimate by using a common structure). I'm more sympathetic to the opposite argument. The engineering centred community that has collectively lead to this situation has an unrealistic idea of what 'well constructed' should mean. I'm not saying we need to go all the way back to the anchor bolted = F5 approach, but when the point's reached that the 'expected value' is highly
unexpected it's time to start asking whether it's useful.
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