HurricaneJosh

I've been in a bunch of quakes, and like weather events, each one is really unique-- feels completely different. The Northridge quake was extremely violent and very vertical-- you really felt things going up and down, in a fast, jerky motion. We had one a year or two ago that was mellow and horizontal-- like slipping on ice-- it just felt like everything was sliding. Each one is its own thing.

We might be talking about different things. P and S waves cause two different types of motion and are used to locate the earthquake's center: http://en.wikipedia.org/wiki/Seismic_wave Re: shallow quakes... The shallow ones tend to have a sharper, edgier feel, I've found.

Yes. Usually the first waves are more mild and they give you a chance to duck and cover before the heavier stuff comes. Now, if you're right at the epicenter, you just get slammed all at once, and there's no difference-- whereas the further you are from the center, the more time there is between the P and S waves.

Wow-- not bad for this region.

Wow-- it sounds like FEMA has really stepped up to the plate. The temporary housing sounds really nice. Awesome to hear when things are working right in this country!

It's nice to see a more detailed report, although I'm disappointed they still haven't assigned a max wind-speed value to the event.

Yeah, that happened to me. I grew up in NY and within two years of moving to L.A., the city had its biggest and most violent quake in well over over a century (Northridge 1994). Scared the crap out of me.

That's my feeling as well. The core circulation seemed to be embedded in a large envelope of heavy rain and damaging winds that extended well beyond that core.

I didn't feel uncomfortable because this is a weather forum and of course we're going to analyze these events from a technical standpoint. However, if the folks who were affected by this disaster (JoMO, Joplinmet, etc.) would like, perhaps we can make a separate thread for technical analysis, so this one can be more about disaster recovery and human-interest topics. It's a big enough event that perhaps it needs separate threads for these subtopics. I'm cool either way. Anyone have a preference?

Does anyone know when the NWS will come out with the complete, detailed survey of the event? I imagine we'll need to be patient-- an event of this magnitude requires a sh*tload of time to piece together and analyze-- but I was just curious if anyone knew. I'm particularly interested in what the max wind estimate ends up being-- to see if they go over the 210-mph benchmark we've seen with a couple of other EF5s.

OK, so not nearly as short as we all first thought. Wasn't the initial estimate like 4 mi or something like that? We all couldn't believe such a strong tornado could be so short-lived. 22 mi makes a lot more sense. Also, does anyone have a clear idea of the circulation's translational speed as it passed through Joplin? I had thought it was very fast-- that it barreled through at well over 40 mph-- but the big article posted above (several pages back) said it was more like 10 mph. Any thoughts, anyone?

Agreed. But what about the hospital, Walmart, and Home Depot? Those structures structures all survived to some degree, and I believe they would all at least partially withstand 210-mph winds-- so I would think they could give clues Re: higher speeds-- no?

The EF scale has been used for 4 years now, and the sample set of EF5s is very small. From this sample set, I haven't seen any value over 210 mph mentioned. Given this, it seems logical that the low-end would be restricted to 205 mph, or else every single observed EF5 is "low-end", and the descriptor therefore has no meaning. If the reports start mentioning tornadoes with winds of 230 mph, then perhaps I could consider 210 mph "low-end" as well. Right now, though, 210 mph seem to be the "high end".

Personally, I consider 140 kt low-end Cat 5 and 145 kt borderline low-end/medium. But that's beside the point, because with 'canes, it's totally different. Although the SS scale is open-ended, hurricane winds are actually be measured (as opposed to exclusively estimated based on damage), and based on this, we have a good idea of the upper limit in the N Atlantic, which seems to be ~165 kt. So although the scale is open-ended, decades of recon data give us a pretty-clear upper limit. Given this, one can say: 140-145 kt = low-end 150-155 kt = medium 160-165 kt = high-end With tornadoes, this is all theoretical. With the new EF scale, which has only been applied for a few years, we really have no idea what the upper limit is, and so saying "low-end" or "high-end" doesn't make sense. Twenty years from now, surveyors can come to the conclusion that tornado wind speeds really can't exceed 220 mph-- in which case, 210 mph wouldn't be "low end"-- whereas if they estimate some tornadoes have winds of 250 mph, then 210 mph would be "low-end".

Since the scale is open-ended, there can be no high-end.

But then why even say "low-end", if that's the norm? P.S. I would consider 205 mph low-end, but not 210 mph or more. Given that each scale range is only ~30-35 mph, I would consider 10 mph above the threshold well into that range.

Weird-- I'm almost disappointed with that assessment! We were all expecting this one to break some kind of record in terms of estimated wind speed.