Joplin, Missouri Tornado Assessment - recommendations

[B-Rent]

Eh, the siren really doesn't benefit someone like me anyway. I usually stay informed when I know severe wx is possible/happening. Chances are I know about the warning before the siren even goes off.

True story. I had a huge post wrote about sirens, cell phones, sociology, and the such. I hit F5 on the wrong screen and lost it. Suffice to say I can sum it up like this:

Sirens suck. Cell phones are the new medium that needs explored. The NWS needs to focus on sociology and psychology of warnings.

[Kenny G]

Lone Oak, Kentucky - a suburb of Paducah, Kentucky - blows their siren for fires. If there is a fire or car accident then they set the siren off in order to alert their volunteer firemen. There used to not be cell phones - texting - other methods to reach people. Thus the siren. They continue this practice to this day. It is extremely frustrating. I don't know how many people ask me why the sirens are going off. As you can imagine it is not uncommon to have a car accident or fire during a thunderstorm (lightning, slick roads, hydroplaning).

I have little doubt that people are going to lose their lives because of this practice. It is just a matter of time before the confusion occurs during a tornado event.

Same for my small town of Berryville, VA. The day I moved in I asked my landlord if we were having a tornado. She said it was for fires & accidents. I agree with you. There would be major confusion.

[CT Rain]

My personal beliefs, based partially on this ongoing work, is that the error bars are probably a large fraction of an EF scale. The work I just linked is the first real attempt to verify surveys with scientific wind measurements. As you can see, the results are shockingly poor. In fact, I would advocate changing from 6 EF categories to 3: weak, moderate, severe.

I do not agree with estimating wind measurements to the nearest 5 mph from surveys alone, I do not believe there is evidence that surveys provide that type of precision.

This.

I think this is probably the only accurate way to describe the damage. I don't know the value in trying to determine the difference between EF3 or EF4, etc.

[AtticaFanatica]

This.

I think this is probably the only accurate way to describe the damage. I don't know the value in trying to determine the difference between EF3 or EF4, etc.

The argument against it is that it ruins the climatology, but since you're moving backwards essentially, you can re-categorize previous ratings.

I don't see the point of having a climatology if the data within it are as bad as it seems like they are. I'd normally wait for the work to hit peer review, but I know enough about this stuff that I know the work is solid.

[HurricaneJosh]

But even if you only have three categories, that wouldn't completely solve the problem, as trying to tell to classify a borderline moderate-severe tornado would theoretically present the same challenges as trying to classify a borderline EF3-EF4.

[CT Rain]

But even if you only have three categories, that wouldn't completely solve the problem, as trying to tell to classify a borderline moderate-severe tornado would theoretically present the same challenges as trying to classify a borderline EF3-EF4.

But assigning 6 ratings gives a false impression of precision, IMO.

[HurricaneJosh]

But assigning 6 ratings gives a false impression of precision, IMO.

Perhaps. But on the flip side, only three broad categories means that you could have situations where what we now call a low-end EF4 and a high-end EF1 could both conceivably receive the same classification: strong. In that case, you have to wonder what the value of such a broad scale is.

Anyhoo, tornadoes are not my area of expertise, so I defer to you guys. Like I said, I'm just glad that with tropical cyclones, we actually can class them into one of seven categories with reasonable-- if not airtight-- certainty.

[AtticaFanatica]

But even if you only have three categories, that wouldn't completely solve the problem, as trying to tell to classify a borderline moderate-severe tornado would theoretically present the same challenges as trying to classify a borderline EF3-EF4.

you'd get a much higher % of tornadoes correctly rated

[AtticaFanatica]

Perhaps. But on the flip side, only three broad categories means that you could have situations where what we now call a low-end EF4 and a high-end EF1 could both conceivably receive the same classification: strong. In that case, you have to wonder what the value of such a broad scale is.

That's justifiable when the actual ratings are EF1 +/- 1 rating and EF4 +/- 1 rating which is what they actually are; the survey pretends it's "low end EF4" and high end "EF1", when we really don't know that.

[AtticaFanatica]

Josh, OT a bit, but since it's my area, I thought I'd mention it, you should look into the mobile radar obs of hurricanes. They see some pretty cool stuff, like "wind streaks", local enhancements in the flow over very small areas.

[HurricaneJosh]

That's justifiable when the actual ratings are EF1 +/- 1 rating and EF4 +/- 1 rating which is what they actually are; the survey pretends it's "low end EF4" and high end "EF1", when we really don't know that.

I'm talking theoreticals here. What I mean is that the range that "moderate" covers would be so huge, I wouldn't really know what is meant by that classification, except that it's definitely not a Joplin tornado and definitely not a little pencil vortex that breaks off tree branches. If you're comfortable with that lack of specificity, so be it.

[AtticaFanatica]

I'm talking theoreticals here. What I mean is that the range that "moderate" covers would be so huge, I wouldn't really know what is meant by that classification, except that it's definitely not a Joplin tornado and definitely not a little pencil vortex that breaks off tree branches. If you're comfortable with that lack of specificity, so be it.

I see what you're saying. That's the tradeoff I guess, I don't feel comfortable with the ratings now, because when I hear "EF3" tornado, I know, based on the work done on the matter, that there's a good chance (40-50%?) that the rating is wrong. I'd rather be more accurate even if it's an admission that our precision is not what we once hoped.

[HurricaneJosh]

I see what you're saying. That's the tradeoff I guess, I don't feel comfortable with the ratings now, because when I hear "EF3" tornado, I know, based on the work done on the matter, that there's a good chance (40-50%?) that the rating is wrong. I'd rather be more accurate even if it's an admission that our precision is not what we once hoped.

OK, gotcha. I guess it is kind of a trade-off either way.

[BeauDodson]

It seems like part of the problem is that there are way too many tornado false alarm warnings being issued. 70% or something like that? I am in the camp that wishes they would do severe thunderstorm warnings for squall line events and simply mention that there could be brief tornadoes. Save the tornado warnings for the higher end events - the well defined radar indicated tornadoes - the spotter verified tornado warnings. We have seen sooooo many of these blanket tornado warnings this year - mostly with the squall line events. Sure you might capture a small/brief/weak tornado but is that worth it - is it saving lives? Are we tuning out tornado warnings because there are just so dang many of them?

I used to think tornado emergencies were a bad idea. Now, though, I wonder. After what has happened this year. It is a slippery slope with warnings. Do we need super severe thunderstorm warnings for the derecho events that produce widespread 80-100 mph winds?

I don't know. There is no easy answer. We are dealing with sociology when it comes down to it. What will make people take shelter - what won't. If people need more than one verification point in order to make that decision then we need to take that into account. And I believe we do. We tell people to tune into local media - watch the wall to wall coverage - alert them about the higher end event days - tell people on high risk days to pay special attention.

I am not sure what the answer is when it comes to blowing the outdoor sirens. Regardless of what we would like people to believe (that outdoor sirens are for people outdoors) we have way too many people who use them as their warning device. They could have their own personal warning system for a few bucks - the NOAA All Hazards Weather Radio. It also has a siren and some models can be programmed for tornado warnings only. The Midland WR 300 being one of them.

Love that radio.

[AtticaFanatica]

So you're cool with a lower POD? Because that's where we are with the science.

[The Great Zo]

Remember that trying to use the high FAR as an argument against squall-line tornado warnings is somewhat disingenuous. Due to the nature of the simplicity of the official metrics, large tornado warnings actually tend to favor a lower FAR (one weak tornado verifies the entire warning).

Perceived false alarm is much more applicable when discussing the social science of these things, but there's practically no way to quantify that (although some sort of areal false alarm statistic would help). Obviously, squall-line warnings are a big part of this issue.

Independent of the statistics, the current state of the science (as it relates to using WSR-88D and TDWR systems) does not allow for much further improvement on the accuracy of tornado detection. This important fact was left out of many news articles about the Joplin assessment, which unfortunately left the FAR number to stand on its own as an incomplete and unflattering reflection of NWS performance.

[JoMo]

It seems like part of the problem is that there are way too many tornado false alarm warnings being issued. 70% or something like that? I am in the camp that wishes they would do severe thunderstorm warnings for squall line events and simply mention that there could be brief tornadoes. Save the tornado warnings for the higher end events - the well defined radar indicated tornadoes - the spotter verified tornado warnings. We have seen sooooo many of these blanket tornado warnings this year - mostly with the squall line events. Sure you might capture a small/brief/weak tornado but is that worth it - is it saving lives? Are we tuning out tornado warnings because there are just so dang many of them?

I used to think tornado emergencies were a bad idea. Now, though, I wonder. After what has happened this year. It is a slippery slope with warnings. Do we need super severe thunderstorm warnings for the derecho events that produce widespread 80-100 mph winds?

I don't know. There is no easy answer. We are dealing with sociology when it comes down to it. What will make people take shelter - what won't. If people need more than one verification point in order to make that decision then we need to take that into account. And I believe we do. We tell people to tune into local media - watch the wall to wall coverage - alert them about the higher end event days - tell people on high risk days to pay special attention.

I am not sure what the answer is when it comes to blowing the outdoor sirens. Regardless of what we would like people to believe (that outdoor sirens are for people outdoors) we have way too many people who use them as their warning device. They could have their own personal warning system for a few bucks - the NOAA All Hazards Weather Radio. It also has a siren and some models can be programmed for tornado warnings only. The Midland WR 300 being one of them.

Love that radio.

Springfield had an 85% FAR in 2010 until May 22nd 2011.

This summer on Aug 10th, there was a squall line that produced an EF-2 tornado which killed someone in a mobile home in Locust Grove, OK. The thunderstorm was only severe warned with "winds of 70 MPH" in the warning.

[Hoosier]

The squall line/blanket tornado warning issue isn't an easy one. I don't know if there's any data out there to support this but it seems like these are particularly prone to becoming rain wrapped (which of course heightens the danger). They may tend to be weaker than discreet supercellular tornadoes but there are certainly plenty of instances of significant tornadoes happening in squall lines. I guess my concern with reducing the number of blanket tornado warnings is where it would stop. If you never tor warn a squall line, you'd willfully ignore a lot of tornado events.

[B-Rent]

The squall line/blanket tornado warning issue isn't an easy one. I don't know if there's any data out there to support this but it seems like these are particularly prone to becoming rain wrapped (which of course heightens the danger). They may tend to be weaker than discreet supercellular tornadoes but there are certainly plenty of instances of significant tornadoes happening in squall lines. I guess my concern with reducing the number of blanket tornado warnings is where it would stop. If you never tor warn a squall line, you'd willfully ignore a lot of tornado events.

Many of our sqall line events, are over nighters anyway, so I don't think the rain wrapped-reduce viz really works in that arguement.

[thewxmann]

The squall line/blanket tornado warning issue isn't an easy one. I don't know if there's any data out there to support this but it seems like these are particularly prone to becoming rain wrapped (which of course heightens the danger). They may tend to be weaker than discreet supercellular tornadoes but there are certainly plenty of instances of significant tornadoes happening in squall lines. I guess my concern with reducing the number of blanket tornado warnings is where it would stop. If you never tor warn a squall line, you'd willfully ignore a lot of tornado events.

I think we should implement some type of "squall line warning" that differentiates linear systems from discrete cells. This squall line warning would warn for damaging winds and brief spinup tornadoes.

[B-Rent]

I think we should implement some type of "squall line warning" that differentiates linear systems from discrete cells. This squall line warning would warn for damaging winds and brief spinup tornadoes.

No offense, but that sounds about as handy as an alert tone for a warning, and a long tone for on the ground. The public still after 30+ years doesn't get the diffrence in a watch and a warning. How should they know what the hell a squall line warning means?

[AtticaFanatica]

I think we should implement some type of "squall line warning" that differentiates linear systems from discrete cells. This squall line warning would warn for damaging winds and brief spinup tornadoes.

I think this is a very bad idea.

[on_wx]

I think we should implement some type of "squall line warning" that differentiates linear systems from discrete cells. This squall line warning would warn for damaging winds and brief spinup tornadoes.

They already do that?

* AT 1043 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A

SEVERE SQUALL LINE CAPABLE OF PRODUCING BRIEF RAIN-WRAPPED

TORNADOES IN ADDITION TO WIDESPREAD STRAIGHT LINE WIND DAMAGE.

ALONG A LINE EXTENDING FROM 6 MILES SOUTHWEST OF SCHOOLCRAFT TO 6

MILES NORTHWEST OF CONSTANTINE TO 4 MILES NORTHEAST OF BRISTOL...

AND MOVING EAST AT 50 MPH.

As opposed to the more typical...

* AT 324 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A

SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO...NEAR

HOPEULIKIT...MOVING NORTHEAST AT 30 MPH.

[thewxmann]

No offense, but that sounds about as handy as an alert tone for a warning, and a long tone for on the ground. The public still after 30+ years doesn't get the diffrence in a watch and a warning. How should they know what the hell a squall line warning means?

We have warnings for just about everything now, so adding one isn't going to screw over the public. And what I meant wasn't exactly a "squall line warning" verbatim (since 99% of the public won't know what a squall line is), just a warning designed specifically for QLCS damaging-wind spinup-tornado situations.

[thewxmann]

I think this is a very bad idea.

Care to elaborate as in why?

[AtticaFanatica]

Care to elaborate as in why?

Any warning that attempts to differentiate tornado intensity is not supported by the available science. A "brief, spin-up" EF-0 tornado can kill you, either warn for the tornado or don't, it's an unnecessary distinction that cannot be accurately made and does not serve the public.

[The Great Zo]

Any warning that attempts to differentiate tornado intensity is not supported by the available science.

While I agree that radar science is limited (with respect to tornado detection), certainly there are clear differences in the radar depictions of an EF4 or EF5 like Tuscaloosa or Joplin, and a squall line whose elements contain little to no discernible rotation. Sure, these are extremes, and being too explicitly specific in the grey area in between is only possible to a certain extent. However, distinctions in threat level can be made in some cases, and the service assessment's proposal for an impact-based, tiered warning program is clearly in support of this.

[Stebo]

I think we should implement some type of "squall line warning" that differentiates linear systems from discrete cells. This squall line warning would warn for damaging winds and brief spinup tornadoes.

I would be against this, because there have been instances of squall lines producing EF-2 and 3. It is just hard to delineate strength right now with radar representation. Plus we have seen EF0s and 1s kill people before so we should treat all tornadoes as being equally dangerous.

[Amped]

Easy, Cellers and probably sirens when the tornado warning happens and a second siren when you are in the clear.

But Joplin faired pretty well, my initial death toll guess was too high by a factor of 10.

[AtticaFanatica]

While I agree that radar science is limited (with respect to tornado detection), certainly there are clear differences in the radar depictions of an EF4 or EF5 like Tuscaloosa or Joplin, and a squall line whose elements contain little to no discernible rotation. Sure, these are extremes, and being too explicitly specific in the grey area in between is only possible to a certain extent. However, distinctions in threat level can be made in some cases, and the service assessment's proposal for an impact-based, tiered warning program is clearly in support of this.

I was referring to prior to genesis.