HurricaneJosh

Back to the meteorological aspects (sorry!)... Do y'all know when the Springfield NWS office plans to release the complete, detailed survey and official max wind estimate? How long does it usually take after a big event like this? I'm just very curious to hear the final metrics with regard to intensity, size, etc.

No. No, I can't, honestly. I also can't imagine a huge neighborhood reduced to rubble in two minutes. It's all very surreal. This is the truly ugly side of this thing which so fascinates all of us here. These are really upsetting stories-- I almost wish I didn't read them. You might find that you're having "survivor's guilt", which sometimes happens to people after catastrophes like this. It's completely normal, but if you find that you're having trouble with it, you can perhaps talk to someone. There's nothing wrong with that.

Well, JoMo can look at it philosophically. He's a weather dude and he experienced firsthand what I'm convinced is one of the most important American weather events of then past century. I really think this is up there historically. It's a truly chart-smashing sort of event. This will be a benchmark event that's referred to and compared to in countless discussions and media stories 50 and 100 years from now.

Ah, OK. That makes sense. Thanks. So you were in the yellow zone but you feel like you had EF0? Even that, though. D*mn. It's just nuts how close it passed to you-- maybe the strongest tornado in modern U.S. history. You must be having serious gratitude, dude.

Wow. That is just crazy. I can see how these places become unrecognizable to you. Without even the trees, there are just about zero visual cues to help you make the connection. I noticed on the contour map-- the one we were discussing so vigorously this morning-- that the tornado passed just S of downtown and might have grazed it. Did the downtown area have any damage from inflow winds or anything?

That makes more sense. So you were in the yellow area? Wow-- awful close, dude. I think you're right, but how else can we compare historic events? Or are you saying we can't? Agreed. But the trend since the early 1970s has been to lower estimates down from the previous nuttiness-- so an estimate of 250 mph sounds weird. P.S. When I was in grade school-- in the late 1970s-- textbooks still said that winds in tornadoes reached 400-600 mph. I kid you not.

The official estimated max winds in Greensburg and Parkersburg-New Hartford were 205 mph. Where did you get those higher values? I agree with you-- that 225 mph seems like a more reality-based value for Joplin, simply because the higher value (250 mph) would be a whopping 25% higher than other EF5s-- something which is hard to believe. P.S. Good point-- that these are simply estimates. Lord knows how accurate they really are. I'm sure there's a wide error range when talking winds this high.

Yeah, the death toll is bizarre in light of these other events-- especially Topeka, which rammed through downtown and killed less than 20 people! Curiouser and curiouser, this one.

Thanks, Tony. Yeah, I've been wondering about the 250 mph estimate. If I read correctly, they described the speed as "instantaneous" or something like that, which lead me to believe that the 3-sec value (upon which the EF scale is based) would be lower-- right? I am having a hard time getting my head around the idea of a tornado with winds 25% stronger than Greensburg and Parkersburg. I mean, that doesn't even make sense to me. Like you, I am kind of shocked to hear a figure like that even mentioned in the "Enhanced Fujita Era". It looks like this really might be a contender for strongest surveyed tornado. Just wow. Just bizarre.

I see JoMo lurking. JoMo, were you in one of the colored areas? If so, which one?

Everyone-- Check out this map: http://maps.google.com/maps?f=q&source=embed&hl=en&geocode=&q=http:%2F%2Fwww.crh.noaa.gov%2Fimages%2Fsgf%2Fevents%2F2011may22%2FJoplin_damage_path_all.kmz&aq=&sll=37.05253,-94.475199&sspn=0.20276,0.299034&ie=UTF8&ll=37.057369,-94.478302&spn=0.131512,0.219727&t=p&z=12 Uncheck all of the boxes except F5. Then zoom in real close and look at how many houses and buildings this presumed EF5 area encompasses.

Yep. Tony's about to post-- curious what his opinion is.

Yeah, see above. winterymix pointed out the menu on the left, where you can check and uncheck the isotachs to make them appear and disappear. But, you're an expert in this stuff. Do you believe the EF5 damage area is that large and solid?

OK, cool. I looked at it and I see what you're saying. When you check and uncheck the EF5 checkbox, that inner isotach appears and disappears. So, we now know they did, in fact, mean EF5. That mystery is solved. It doesn't change my skepticism a bit. I can only assume that map is meant as an extremely rough approximation.

Correct, there were other instances of F5 damage in that storm. My point is simply that when there are instances, they're highly localized. The Parkersburg-New Hartford tornado produced EF5 damage in two towns very far apart-- but the instances were isolated. Ugh-- me, too!

I wouldn't say it's obvious, due to the confusion Re: the colors. (See our discussion above.) Also, I strongly doubt that that is what occurred on the ground. It might have been the strongest tornado in the history of the USA. Even so, I don't buy solid EF5 damage over that large an area.

I see tornadotony lurking. I'd like to hear his opinion-- he's an expert on this topic. Tony?

As an example of what I'm talking about... This is is from the preliminary survey of the Moore, OK, tornado. Even with that one, it was only a small handful of homes that received F5 damage: THE WORST DAMAGE SEEN ALONG THIS ENTIRE PART OF THE PATH WAS IN THE EASTLAKE ESTATES... NORTH OF 134TH AND BETWEEN PENN AND WESTERN. ENTIRE ROWS OF HOMES WERE VIRTUALLY FLATTENED TO PILES OF RUBBLE. FOUR ADJACENT HOMES ON ONE STREET WERE VIRTUALLY CLEANED OFF OF THEIR FOUNDATIONS... LEAVING ONLY CONCRETE SLABS. THESE HOMES EARNED THE F5 RATING...

I understand why you reach that conclusion-- because it's logical, given that there are 5 colors in the legend and 5 colors on the map. I'm wondering if maybe that inner isotach equals high-end EF4 vs. lower-end EF4-- like a half-grade indicator. I know that might sound ridiculous, but I find it almost impossible to buy the idea of an EF5 damage area being that large, when for every other F5/EF5 historically, the instances were just a house or two or maybe a handful of homes at one end of a subdivision.

Weird. On my computer the colors don't match, even when I zoom in real close. EF5 in the legend is a heavy, brick red, and there is no such color on the map. Also, look at the size of that area-- it is huge. There would need to be solid EF5 damage to over 50 or maybe even 100 homes to justify that isotach if it means EF5.

I see the slightly darker "inner" isotach as well-- but the problem is that the colors on the map don't match the colors on the legend, so it's hard to know what values these shades map to. Even with this tornado, I would be skeptical Re: the idea of a continuous, unbroken swath of EF5 damage going for several miles like that.

I was wondering about those values (225 and 250 mph). Two things: 1) I heard that those were "instantaneous" speeds, whereas a tornado is rated as per the highest estimated 3-sec value-- so I wonder if perhaps those peak values wouldn't count as the official value (sort of how a hurricane is referred to by its max 1-min wind, not peak gust). 2) I am having a hard time imagining that the official max estimated wind speed for this tornado would be a whopping 12-25% higher than the Greensburg and Parkersburg values (205 mph). That would be almost inconceivable. But then again, maybe it really was that unique of an event.

Yep. Personally, whenever I see a shot of a neighborhood mowed down, my assumption is always F4/EF4 unless the engineers on the ground specifically cite instances of EF5 damage. In this case (Joplin), the survey team determined at least four EF5 instances, whereas in Tuscaloosa, they didn't find any. It just goes to show that we can't tell just looking at a few photos. The popular litmus test-- "Was the house swept off its foundation?"-- isn't even sufficient evidence in itself, as we saw in La Plata, MD. Back to Joplin... I really do hope they do some very detailed plotting of the damage-- so we can see just how extreme this event was.

Not to disagree here, but I don't think it's possible to make a determination of continuous EF5 damage from a casual glance at a single aerial shot. If it were that easy, they wouldn't need to send in the dudes to do the ground surveys. Also, like I mentioned above, EF5 damage is usually determined to have occurred in spot instances-- not a continuous swath. What we definitely do see is a continuous swath of very heavy (EF3+) damage.

Yep-- I looked it up after that discussion last night. It's d*mn impressive to see that many EF5 instances, but this in itself does not suggest that the EF5 damage was continuous between these points. That would be astonishing. (But then again, nothing surprises me about this one anymore.) I hope they do a really detailed damage-swath map-- like this gorgeous one they did for Parkersburg-New Hartford: http://www.crh.noaa.gov/images/dmx/parkersburg/Final-small-PDF-PARKERSBURG-NEW-HARTFORD-IOWA-EF-5-TORNADO.pdf (Notice on this one how the EF5 instances are just dots in a swath of EF4 damage.) I also hope in the final survey they settle on a specific max value for the winds-- rather than just "in excess of 200 mph". I'd like to know how this compares with Greensburg and Parkersburg-New Hartford (both of which were estimated at 205 mph).