James Spann speaks to the media and the NWS concerning

[Eskimo Joe]

When Spann talks - people listen

Quite an amazing meteorologists

Article

http://www.alabamawx.com/?p=48699

Clips from the article

I ask the NWS to consider stopping the use of tornado warnings when trying to catch small spin-ups within a squall line (or QLCS). These tornadoes rarely last more than a few minutes, and are next to impossible to detect in advance. And, in most cases, the greatest damage from a QLCS is from widespread damaging straight line winds, not tornadoes.

and

*NOAA Weather Radio must be upgraded to the polygon warning system soon, or it will become obsolete.

Sure, it is the best thing we have now, and I still promote it heavily. But, why hasn’t NOAA upgraded their system so the receiver manufacturers can produce models with GPS included so they sound only when the receiver is a in a warning polygon? If something doesn’t change soon, the private sector will be the ones that push the warning process into the new technological era.

and

*Social media is not a time waster or a novelty, it is a lifeline during severe weather, and must be used by TV meteorologists.

Lives were saved April 27 by pushing tornado information to the masses through Facebook and Twitter. Seems like many old school news directors think this stuff is for high schoolers. How wrong is that; these social media services are mainstream and reaches across all demographics.

And, you just can’t throw up a Twitter or Facebook account and expect to be successful. It takes years of conversation and interaction with followers to grow your numbers and reach critical mass.

Broadcasting is now a conversation. The people that follow you on Facebook and Twitter aren’t idiots… they are our friends that can offer a treasure trove of information during active weather and any kind of breaking news event. They follow you, you follow them. Most media people just don’t get it.

More in his article above...

I consider him the best on-air met during an outbreak. There is a video of him on YouTube during the Superstorm of 1993 and he was nothing short of spectacular.

[Master of Disaster]

Beau, I put this on your Facebook post. Ill just copy and paste here:

About 2 years ago, I gave a speech to a bunch of Chinese engineers at the University of MD. When I asked them what kind of public warning system they use, they told me there are no warning systems. When I asked what they do for a dam break,they told me it is head of each households responsibility to notify their neighbor. When I asked what if he doesn't do that. They replied, he goes to jail and that is the best scenario. Americans need to stop acting like a bunch of babies, stop crying about how they need more warning and just act when told to do so.

[JoMo]

I disagree with him about scrapping the sirens. The rest of what he wrote was pretty good though.

I have a weather radio I don't use because it scared the crap out of me one night for a Flash Flood Watch........

[Master of Disaster]

I disagree with him about scrapping the sirens. The rest of what he wrote was pretty good though.

I have a weather radio I don't use because it scared the crap out of me one night for a Flash Flood Watch........

I agree with him about the sirens. When I first reported to this position. I was an avid siren supporter. But to many jurisdictions use them to notify their volunteer fire departments. We took our sirens out of service several years ago and havent looked back. Where I live in Adams Co, they still use them, and I have a hard time trying to figure out what they mean when they go off. How is someone less involved in public warning suppose to understand.

Here is an article about it:

County Leaders Debate Early Warning Weather Sirens

“We have to depend on people to check on their neighbors . . .”

• <LI class=readerComments>

read comments (0) <LI class=readerRecommends>recommended ( 0 ) <LI class=printPage>print this pageemail this page

Share This Article:

ShareThisPublished on: Thursday, June 02, 2011

By Lauren McLendon and Gina Cairney

When it comes to emergency preparedness in Maryland, several regions throughout Maryland laud the effectiveness of siren alert systems. But some officials in this county do not see a use for such systems in this area considering the successes of technology-based warning systems.

“We want to be able to reach all groups [of people] in the best possible way,” said Montgomery County Fire and Rescue Cpt. Beth Sanford, who added that the county would benefit more from a proactive alert system as opposed to a reactive system, like sirens.

According to Tony Loconte, public warning coordinator in Montgomery County’s Office of Emergency Management and Homeland Security, the county discontinued its siren alert system in 1993 due to “expensive maintenance” and because people were “confused” about what action to take when the sirens blared; the sirens have since been removed.

“I am in no position to judge the effectiveness with respect to an air siren system that we stopped using 17 or 18 years ago,” Councilman Roger Berliner said about the issue. “If our homeland security people and public safety officers believe that that would be appropriate, I would be more than happy to entertain that. I have not heard from them or anyone else with respect to this matter so my views at this point are open to what the experts advise.”

Experts, like Chris Strong, a warning coordination meteorologist for the Baltimore-Washington area unit of the National Oceanic and Atmospheric Administration (NOAA), say there is no blanket answer to the problem.

“Each county's jurisdiction has to look at the pluses and minuses for that area," Strong said.

Across the state — which has been hit by 96 tornados since 2000 — officials have a range of tactics for dealing with emergencies.

In Harford County, there are approximately nine sirens that are used at fire stations to alert people of natural disasters, according to Susan Ayers, a Harford County emergency planner.

"We put out brochures and storm guides," Ayers said about how the county educates people about what the different types of sirens denote.

In Calvert County, Department of Economic Development spokesman Mark Volland said a siren system is tied in with the area’s nuclear power plant “in case of nuclear-related emergencies.”

According to Volland, the sirens have not been used for weather-related emergencies, but the county is evaluating the possible use of sirens for such purposes, in addition to nuclear emergencies.

Similar to Montgomery County’s “Alert Montgomery” emergency notification system, Volland said Calvert County has a code-red system that utilizes text messaging and phone calls to alert the public of any emergencies.

“We want to be prepared ahead of time, instead of waiting for something to strike first,” Volland said.

Other regions in Maryland adopted additional emergency preparedness procedures post-disaster.

In 2002, a tornado touched down in Charles County, leaving a trail of destruction in La Plata. While the tornado started out as an F1 on the Enhanced Fujita Scale, it left some damage that was as devastating as that associated with F3- and F4-level twisters, according to a report on the NOAA website; the Enhanced Fujita Scale rates tornados based on their speed and the severity of the damage they cause on a scale of zero to five, with five being "incredible."

Since then, the town has installed sirens to alert residents in the event of future weather emergencies. According to Lt. Wayne Watson of the La Plata Police, the first siren was a donation from the Wailing Engineering Company, the company contracted by the town to maintain the system. Based on a 2003 quote provided by Watson, the four additional sirens the town purchased cost about $22,000 per tower. Yearly maintenance costs total about $10,000 per year and cover everything from repairing any damages to performing tests on the equipment twice a year.

Although La Plata and Calvert County claim to benefit from having an emergency siren, some within the more urban Montgomery County suggest otherwise, instead asserting that technology-based alert systems are more efficient in alerting the public of any emergencies.

Montgomery County spokeswoman Donna Bigler said one of the benefits of Alert Montgomery is its flexibility. She added that the type of information people want to receive can be customized to fit their unique needs, like traffic updates, school closings and weather emergencies.

“It’s incredibly useful,” she said.

According to Bigler, sirens make sense in places like Joplin, Mo., but in urban areas, they would be less efficient and redundant with the myriad of alert systems already in place, such as through the county website, Twitter feeds and Facebook updates.

“For people who don’t have access [to such technologies], we have to depend on people to check on their neighbors who they know are without that kind of access,” Bigler said.

Montgomery County Public Schools spokesman Dana Tofig said the system’s public information offices have emergency radios and phones in the office that are used to communicate with schools during a natural disaster.

“We use e-mail, ‘quick call’ and the radio to notify schools about any emergencies as soon as we get the information,” Tofig said. “We do whatever planning we can. Safety is our No. 1 priority.”

Between 01/2000 and 02/2011, 96 tornadoes reported in Maryland State

2000 - 10

2001 - 12

2002 - 14

2003 - 9

2004 - 21

2005 - 0

2006 - 3

2007 - 2

2008 - 8

2009 - 10 2010 - 5

http://www.thesentinel.com/mont/Search/siren-follow

[AtticaFanatica]

Tornado sirens are extremely useful if used correctly. Just because some towns don't use them correctly doesn't mean the system should be scrapped. It means they should learn how to use them correctly.

[tornadotony]

I disagree with the QLCS TOR comments because, as mentioned in the comments section of the article, QLCS tornadoes can be quite violent. Hell, at least one of them from the morning of 4/27 was almost EF4. The rest I can pretty much agree with.

[Master of Disaster]

Tornado sirens are extremely useful if used correctly. Just because some towns don't use them correctly doesn't mean the system should be scrapped. It means they should learn how to use them correctly.

Use them correctly or upgrade them too a multi tone system with certain tones reserved for specific events?

[Memphis Weather]

Just my opinions of course...

I don't advocate getting rid of TORs all together in these situations...but I have to agree with James Spann that TOR warnings along QLCSs have gotten completely out of hand in the last couple of years. The NWS is trying to catch every possible EF0 or EF1 along a squall line that may already producing those winds to begin with...and its leading to...in some cases...double the TOR warnings per year at some WFOs...and most problematic...warnings that span an entire linear system. You can clearly see this happening at MEG (Memphis) in the last two years...and this year especially...and I don't hide the fact that I absolutely loathe it.

There are cases where QLCS Tornado Warnings are necessary...where intense and persistent circulations develop and stronger or long-lived tornadoes are possible. Locally...the 1987 W. Memphis and 1994 Germantown Tornadoes were from QLCS systems...not supercells. However...trying to keep POD at a high rate to catch every little tornado out there (that wasn't even being surveyed a few years ago) is not worth the sacrifice we're seeing in the FAR. I can't say for sure of course whether its caused complacency in specific events this year...or perhaps will in possible future events...but I've gotten to where I cringe every time a QLCS is moving into this area...because I know what's coming.

As far as the sirens...I don't know if they should come down all together but improvements should be made...but that's difficult because it can be different how they sound for every city...town...county...etc. Here in Shelby County...the EMA sounds the sirens county-wide for the entire length of a tornado warning...even if the polygon covers just one-square mile of the county. And this year...Shelby County has had 18 tornado warnings (with not one confirmed tornado in the entire county...mind you)...and I have to think fatigue over either the TORs and/or the sirens is going to set in during the next event where it may be a real situation. The vast majority of the TORs have been in QLCS events...where rotation was weak and brief...at best...and was gone often by the time the warning was issued. As somebody who has worked with MEG in the past (as a student volunteer) and couldn't be a bigger fan of theirs (and the NWS)...I found myself just shrugging my shoulders at what they were doing on several occasions this year...which I hated to do.

[JoMo]

I agree with him about the sirens. When I first reported to this position. I was an avid siren supporter. But to many jurisdictions use them to notify their volunteer fire departments. We took our sirens out of service several years ago and havent looked back. Where I live in Adams Co, they still use them, and I have a hard time trying to figure out what they mean when they go off. How is someone less involved in public warning suppose to understand.

Here is an article about it:

http://www.thesentin...ch/siren-follow

After the May 22nd tornado hit Joplin, many areas were without power as well as landline service. Also, cell phone towers had been damaged or destroyed and all circuits were busy and phones would drop calls. The only thing we had to rely on when there was a tornado warning on May 24th was the sirens and a battery powered radio and the people giving timely information on there. (it was actually a mobile siren since our siren over here is probably several counties away, having been taken out by the tornado. heh)

I've talked to people and read a lot of interviews about people hearing the sirens and taking shelter. Other people simply ignored the sirens, having become used to them. I've also heard a lot of stories of people making cell phone calls to loved ones telling them to take shelter because there's a tornado.

[Bozart]

Spann's advice about Weather Radio is golden. A new generation of receivers that always know where they are, and sound alarms only for their polygon, would be a revolution -- a device that people could take on the road, to the lake or cottage, without having to re-program all the time. NWR monitoring could at last be usefully built into car radios, too -- or any consumer device.

I agree with Spann that smart phones and social media are crucial to the future of warning dissemination. I love my smart phone, and the alerts it brings me. However, I have to pony up $85 a month for that privilege, and my smart phone depends on private firms to send the warning products. A Weather Radio is a modest, one-time expense; and since warning people against surprise disaster is a basic, core public-safety function of government, people should have access to official warnings without having to pay private monthly subscription fees.

Private alert companies might well lobby against Weather Radio modernization. They'd view a host of location-smart consumer devices monitoring the NWR signal as a business threat. But really, consumers would probably want both -- NWR alerts, and their subscription services. As others have noted, people favor multi-source confirmation.

[Hoosier]

I've been a witness to the blanket QLCS tornado warning in my backyard on at least 2 occasions this year...in both of those cases, numerous tornadoes were discovered with several of them rated EF2. I agree about possible warning fatigue and I'm not sure what the answer is. The problem with no QLCS tornado warnings is that when a tornado touches down and does significant damage (even if only for a brief period), then the inevitable "we had no warning" is sure to happen. Hell, you hear that even when tornado warnings are issued with good lead time. I'm not saying I'm the biggest fan of blanket warnings but I certainly support their usage in situations where the background environment is very favorable for tornadoes.

[The Dude]

I ask the NWS to consider stopping the use of tornado warnings when trying to catch small spin-ups within a squall line (or QLCS). These tornadoes rarely last more than a few minutes, and are next to impossible to detect in advance. And, in most cases, the greatest damage from a QLCS is from widespread damaging straight line winds, not tornadoes.

This is a very good point. We need to have something to distinguish a warning based on a radar-indicated potential for small spin-ups, and warnings based on spotter-verified violent tornadoes on the ground. Perhaps we could use Tornado Advisory for the former and Tornado Warning for the latter, or simply expand the use of Tornado Emergency to cover the latter.

[usedtobe]

I've been a witness to the blanket QLCS tornado warning in my backyard on at least 2 occasions this year...in both of those cases, numerous tornadoes were discovered with several of them rated EF2. I agree about possible warning fatigue and I'm not sure what the answer is. The problem with no QLCS tornado warnings is that when a tornado touches down and does significant damage (even if only for a brief period), then the inevitable "we had no warning" is sure to happen. Hell, you hear that even when tornado warnings are issued with good lead time. I'm not saying I'm the biggest fan of blanket warnings but I certainly support their usage in situations where the background environment is very favorable for tornadoes.

I agree with his statement. It's easy to criticize warning but right now the technology is not there to tell whether a vortex signature has an F2 associated with it. That's a big rub. As to whether the high FAR led to deaths in the super or Joplin outbreaks, I've got my doubts. In both cases the NWS had talked up the potential for a significant outbreak well in advance. When you get EF4 or 5 tornadoes, you're in a heap of trouble unless you can get under ground. I guess I disagree with some of the implications made by Spann.

Without a doubt the NWS does overwarn but I'm not sure with the current technology whether not warning is the way to go. People have to make there own judgements about risk. Even with perfect warnings with no false alarms, I have a feeling some people would not take action as tornadoes have sucha small scale the odds of getting hit are low. The trouble is if you live in a mobile home and get hit with a tornado, you're probably going to get hurt of killed.

I agree about the need fro improvements to NOAA Weather Radio. It would be nice if the alert system had a GPS with it an only alerted the owner if a tornado warning was in that county of the one immediately upstream. Of course having a GPS might make it cost too much and might be viewed as competition with the private sector.

[Master of Disaster]

I agree with his statement. It's easy to criticize warning but right now the technology is not there to tell whether a vortex signature has an F2 associated with it. That's a big rub. As to whether the high FAR led to deaths in the super or Joplin outbreaks, I've got my doubts. In both cases the NWS had talked up the potential for a significant outbreak well in advance. When you get EF4 or 5 tornadoes, you're in a heap of trouble unless you can get under ground. I guess I disagree with some of the implications made by Spann.

Without a doubt the NWS does overwarn but I'm not sure with the current technology whether not warning is the way to go. People have to make there own judgements about risk. Even with perfect warnings with no false alarms, I have a feeling some people would not take action as tornadoes have sucha small scale the odds of getting hit are low. The trouble is if you live in a mobile home and get hit with a tornado, you're probably going to get hurt of killed.

I agree about the need fro improvements to NOAA Weather Radio. It would be nice if the alert system had a GPS with it an only alerted the owner if a tornado warning was in that county of the one immediately upstream. Of course having a GPS might make it cost too much and might be viewed as competition with the private sector.

Excellent points overall.

[Memphis Weather]

Simply...a balance has to be found on Tornado Warnings. As said...I'm not personally advocating no TORs on QLCS-only events. Strong/deadly tornadoes do occur within them. But it can be better accomplished I believe than putting out a Tornado Warning for dozens or even hundreds of square miles as a "just in case" measure...which I have personally seen in this CWA this year...as well as others. But...its not as simple as just ignoring these completely and just hoping no tornado touches down...as the alternative could have disastrous results. So...again...there just needs to be a balance...and I feel the balance has shifted too much in one direction recently.

We have at least one Television Weather Personality in Memphis...who is the chief of that station...and is by far the most watched and trusted TV station/personality in this region...who will go on-air and tell his broadcast audience that certain Tornado Warnings can be ignored...and no Tornado is to be expected...and has gone as far as to call the local NWS office and their warnings "useless" and "ridiculous". And he has done this many times in the last couple of years...in multiple events. In fact...he has done this with every event with tornado warnings this year except 4/26 and 5/25...the two High-Risk days in this region. While this is an extreme case and the issue between that person and the local WFO is a lot deeper than simple blanket Tornado Warnings (I have some personal knowledge of this situation)...its clear with Spann's comments that there are a lot of trusted people in the broadcast community who are starting to get more frustrated with the warning process in recent years than they have before...and the NWS needs to keep a good relationship with these people because more than the NWS directly...that's where the general public is getting their weather information from and perhaps basing action decisions off of.

[isohume]

I ask the NWS to consider stopping the use of tornado warnings when trying to catch small spin-ups within a squall line (or QLCS). These tornadoes rarely last more than a few minutes, and are next to impossible to detect in advance. And, in most cases, the greatest damage from a QLCS is from widespread damaging straight line winds, not tornadoes.

This is untrue. Our area frequently sees QLCS, Broken S, and non-classical supercell tornadoes. They can do quite a bit of damage and cause deaths and injuries not seen with their parent MCS straight line winds. Often the lead time is comparable to mesocyclone tors and they certainly last more than a few minutes. They last volume scans and they often reform a few times within the same polygon. To take away warnings for these types of tornadoes would be highly irresponsible to the public.

*NOAA Weather Radio must be upgraded to the polygon warning system soon, or it will become obsolete.

Sure, it is the best thing we have now, and I still promote it heavily. But, why hasn’t NOAA upgraded their system so the receiver manufacturers can produce models with GPS included so they sound only when the receiver is a in a warning polygon? If something doesn’t change soon, the private sector will be the ones that push the warning process into the new technological era.

The private sector does need to and easily could bump the technology with regard to this issue. All the lat/long info of warning polygons and storm position/track are already available to our end users. All it would take is a receiver advanced enough to figure out if it's specific location is within a specific polygon. This could be done through simple GPS and additional coding I'm sure. This would be a great added feature to NWR users I'm sure. I think the reason weather radios haven't advanced along with the polygon era is that there just aren't that many people using it compared to other outlets like the media and the Internet. There hasn't been a need voiced from that community and the private sector has not responded accordingly.

[Hoosier]

Simply...a balance has to be found on Tornado Warnings. As said...I'm not personally advocating no TORs on QLCS-only events. Strong/deadly tornadoes do occur within them. But it can be better accomplished I believe than putting out a Tornado Warning for dozens or even hundreds of square miles as a "just in case" measure...which I have personally seen in this CWA this year...as well as others. But...its not as simple as just ignoring these completely and just hoping no tornado touches down...as the alternative could have disastrous results. So...again...there just needs to be a balance...and I feel the balance has shifted too much in one direction recently.

I agree about balance...it's just tough to know what the right balance is in QLCS events as the couplets are often transient or sometimes don't really show up at all.

I mentioned a couple cases this year in my local area - one of them was 4/19. Here is a fcst sounding that I saved...these parameters more or less panned out. Convection had evolved into a long north-south QLCS, but when you have this type of environment in place with couplets quickly popping up, I don't blame the NWS for erring on the side of caution.

[isohume]

This is a very good point. We need to have something to distinguish a warning based on a radar-indicated potential for small spin-ups, and warnings based on spotter-verified violent tornadoes on the ground. Perhaps we could use Tornado Advisory for the former and Tornado Warning for the latter, or simply expand the use of Tornado Emergency to cover the latter.

Lol...if we waited for a tor to be verified and relayed to the office by a spotter, we wouldn't be issuing enough TORs for actual tornadoes and issuing way too many for "scary looking" scud clouds.

[The Great Zo]

I'm not reading this as if Spann is trying to deter the NWS from issuing tornado warnings for legitimate, trackable couplets that form within squall lines or broken-S signatures. By all means, public safety warrants that warnings should be issued on these features, and the science certainly supports that said features can occasionally produce tornadoes of the EF2 or EF3 variety.

The phenomena he's referring to is something different entirely -- large-scale tornado warnings that are issued without specific circulations being detected on the radar. We know that the shear axis along a well-defined gust front or wind shift in a squall line can produce brief spin-ups, but these are rarely long-lived or significantly dangerous. Furthermore, they are virtually impossible to detect on the radar.

[isohume]

I'm not reading this as if Spann is trying to deter the NWS from issuing tornado warnings for legitimate, trackable couplets that form within squall lines or broken-S signatures. By all means, public safety warrants that warnings should be issued on these features, and the science certainly supports that said features can occasionally produce tornadoes of the EF2 or EF3 variety.

The phenomena he's referring to is something different entirely -- large-scale tornado warnings that are issued without specific circulations being detected on the radar. We know that the shear axis along a well-defined gust front or wind shift in a squall line can produce brief spin-ups, but these are rarely long-lived or significantly dangerous. Furthermore, they are virtually impossible to detect on the radar.

We never issue unless there is a definite gate to gate couplet or refl pattern. I'm not sure what you are referring to. I've never seen a TOR issued for a large scale shear axis.

[tornadotony]

We never issue unless there is a definite gate to gate couplet or refl pattern. I'm not sure what you are talking about. I've never seen a TOR issued for a large scale shear axis.

It happens all the time. And often times, 20 or more EF0-EF1 tornadoes end up verifying out of them.

[Memphis Weather]

We never issue unless there is a definite gate to gate couplet or refl pattern. I'm not sure what you are referring to. I've never seen a TOR issued for a large scale shear axis.

Its happened quite a few times in the MEG CWA this year. Not in one case has it resulted in even one EF0 tornado being confirmed.

EDIT...I'll take that back. There was an EF0 and EF1 associated with the QLCS on April 25. But...still considering more than 50% of the MEG's warnings this year have been QLCS-based...its not had good verification results.

[isohume]

It happens all the time. And often times, 20 or more EF0-EF1 tornadoes end up verifying out of them.

I've never seen them out of our or our surrounding offices. But as long as they catch tors they're warranted. That must be more of a midwest/plains type practice.

[The Dude]

Lol...if we waited for a tor to be verified and relayed to the office by a spotter, we wouldn't be issuing enough TORs for actual tornadoes and issuing way too many for "scary looking" scud clouds.

True enough.

My key point is simply that right now the same terminology "Tornado Warning" can mean anything from a relatively weak radar-detected couplet to a confirmed, on-the-ground 1 mile + EF5. I see some utility in deriving some terminology to provide the public with more information about the severity of the threat.

[Stebo]

The problem with QLCS is if you don't warn on the brief couplets how does that look when you end up with 20 tornadoes. You have to look at the opposite of what has been happening as of late. If you don't warn people probably wont take cover. Warning fatigue or not, it is still essential to warn if there is sufficient evidence that there could be a potential tornado. Looking at radars you can't with 100% certainty tell the strength of a tornado yet. It may look like a EF-0 or 1 and then you end up with EF-2 or 3 damage.

[isohume]

True enough.

My key point is simply that right now the same terminology "Tornado Warning" can mean anything from a relatively weak radar-detected couplet to a confirmed, on-the-ground 1 mile + EF5. I see some utility in deriving some terminology to provide the public with more information about the severity of the threat.

That's why we say in the TOR text "...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO..." or "...TORNADO EMERGENCY..." for highly populated areas. Other times we'll say "...LAW ENFORCEMENT OFFICIALS REPORTED A TORNADO ON THE GROUND...", etc. in the TOR or SVS.

It all depends on how much time you have and additional information you have as to how much you are able to change the default warnng text.

[The Great Zo]

I'm assuming that "20 tornadoes" was an exaggeration, but I have yet to see a situation in which a "shear axis" tornado warning has produced more than a few confirmed tornadoes. Of course, confirming tornadoes in such an environment is dubious -- in a fast-moving line, these weak circulations are entirely outbound-dominant, and these types of tornadoes are extremely small and brief. Sometimes, if you are fortunate to be within a county or two of a TDWR, a circulation might show up for one or two scans (1-2 minutes of real time). Usually, there's no evidence at all. I think that's the key -- is it a good practice to issue tornado warnings for large geographic areas when there is no actual direct evidence in support of them?

[isohume]

I'm assuming that "20 tornadoes" was an exaggeration, but I have yet to see a situation in which a "shear axis" tornado warning has produced more than a few confirmed tornadoes. Of course, confirming tornadoes in such an environment is dubious -- in a fast-moving line, these weak circulations are entirely outbound-dominant, and these types of tornadoes are extremely small and brief. Sometimes, if you are fortunate to be within a county or two of a TDWR, a circulation might show up for one or two scans (1-2 minutes of real time). Usually, there's no evidence at all. I think that's the key -- is it a good practice to issue tornado warnings for large geographic areas when there is no actual direct evidence in support of them?

Probably not and like I said...I've never witnessed such a TOR warning philosophy...based on a large scale shear axis and environmental conditions. It sounds like a warn on forecast procedure to me.

However, Spann specifically mentioned QLCS type tors, which is what we are addressing here.

[Stebo]

I'm assuming that "20 tornadoes" was an exaggeration, but I have yet to see a situation in which a "shear axis" tornado warning has produced more than a few confirmed tornadoes. Of course, confirming tornadoes in such an environment is dubious -- in a fast-moving line, these weak circulations are entirely outbound-dominant, and these types of tornadoes are extremely small and brief. Sometimes, if you are fortunate to be within a county or two of a TDWR, a circulation might show up for one or two scans (1-2 minutes of real time). Usually, there's no evidence at all. I think that's the key -- is it a good practice to issue tornado warnings for large geographic areas when there is no actual direct evidence in support of them?

Not an individual couplet in the QLCS but the last couple QLCS themselves have yielded over 20 tornadoes.

[The Great Zo]

However, Spann specifically mentioned QLCS type tors, which is what we are addressing here.

Well, there's a bit of a semantics issue there. I've heard both types referred to as QLCS tornadoes -- the weak spin-ups, and the legitimate circulations. It sounded to me like Spann was referring to the weaker variety, but I wish the nomenclature was a little bit clearer

(In truth, of course, it's more of a spectrum than a hard line between the two types.)