Monday, May 2, 2011

Reflections on the Tornado Outbreak, and How to Improve Warning Services

These views are my views personally, and do not necessarily reflect the views of the National Weather Service as a whole.

After one of the greatest tornado outbreaks in history, it is crucial to reflect back on what went right, what went wrong, and figure out how we can improve. The National Weather Service will do a thorough service assessment. Although it is too early to say anything conclusive about the NWS's performance in this outbreak, here are some of my thoughts in general (keeping in mind that I work in Alaska, and am not totally up to speed on NWS short-fuse thunderstorm warning services).

We need to focus more on social science, and less on meteorology. The weather conditions that lead to tornados or severe thunderstorms are no secret. Sure, there's room for improvement in meteorological research, such as understanding what exactly makes a regular mesocyclone evolve into an actual tornado. However, all this research is meaningless if the public does not take appropriate actions when severe storms/tornadoes are imminent.

One of the most concerning things to me is that people generally seek confirmation of a threat before taking action. For example, when a tornado warning is issued, people will generally call their friends, turn on the TV, check twitter or facebook, look out the window, or even wait to hear a tornado siren to confirm the threat. This diminishes the effectiveness of the warning and high lead time. In the recent outbreak, many people received this confirmation by watching TV. In particular, the Tuscaloosa/Birmingham tornado was broadcast live by local media. This was an "ideal" scenario: people got blatant confirmation of the threat and were more likely to seek shelter. This underlies the importance of the NWS having a strong relationship with local media, who generally have a better capability to relay the message and inspire people to take actions.

However, what if this "confirmation of the threat" cannot be obtained? Will people take action? This is where analysis of NWS products and services is important. One of the more notable changes in recent years is the addition of "tornado emergency" verbiage, distinguishing the most urgent scenarios from "tornado warnings".  While in certain situations "tornado emergency" can inspire people to take actions, this is not ideal, as it diminishes the importance of tornado warnings. Tornado warnings these days are generally issued for any decent mesocyclone in a storm, which often does not translate to a tornado. Radars are only useful to an extent in detecting if a tornado is on the ground because beams ascend with height as you get further away from a radar. Obviously, having tornado warnings for every mesocyclone can lead to complacency and "warning burnout" for the public, and they may not take appropriate action when the threat is really high. I don't have a great solution for this problem. I do believe that it is valuable for the public to know when there is rotation in a thunderstorm that could produce a tornado. However, in the marginal situations, I would argue that the threat from the thunderstorm itself (hail/straight-line winds/flooding) is just as high as the threat for a small tornado. How can we solve this? Maybe tone down the number of tornado warnings to the high end cases. And, in severe thunderstorms which have a mesocyclone which could produce a tornado, word it as such: "severe thunderstorm warning with a possible tornado", and make two polygons, one being an embedded polygon which will trigger the "possible tornado" wording. Any other ideas?

One other significant problem is that NWS "pathcasts/polygons" are not fully integrated into warning systems. Much larger areas are warned through siren activation/weather radio/etc than need to be. NWS polygons for tornado warnings are fairly precise. If only the people who are physically in these polygons were warned, this would cut down greatly on what the public perceives as false alarms. The technology is out there to accomplish this, but unfortunately is takes money. Here's an idea that I'm sure is being looked into. Many people carry around GPS-enabled smart phones, and this number will only increase, as will coverage. How about a text message alert if the person's smart phone is physically within the polygon? This would be something built into smart phones (ie little configuration required for the user), where the highest end alerts, such as tornado warnings and civil emergency messages, will appear on the smart phone if the phone is within the polygon.

Any other ideas out there on how to improve warning services and inspire people to take appropriate action? Or is there not a problem at all?


  1. There absolutely is a problem here. I noticed the multiple warnings with increasingly 'emergent' verbiage, and we discussed this at our weather office during this outbreak. We, too, wondered why the subsequent warnings with more and more urgent wording? It didn't make sense to us M.T's, and therefore, we believe that it must also not make sense to the lay public. I agree that warnings (tornado), and possibly even tornado watches MUST be overissued in the eyes of someone at upper echelons, otherwise, why would higher ups see the need for the additional product issuance (additional work for already overworked staffs (still shorthanded in a lot of cases), additional work for already overworked city emergency managers,

  2. (...oops, I messed THAT up) and the result is that people are ignoring the watches completely, taking NOTE of the warnings, and taking ACTION when the additional emergency or urgent statements come out. We saw not only the extra tornado warning, but also a warning that stated something along the lines of (can't remember exactly how it was phrased, but... I will paraphrase and someone can correct me...) 'Extremely Dangerous Storm' Warning, on top of a Severe Thunderstorm Watch and subsequent Warning. So not only are the tornado watches and warnings negated, but also the severe thunderstorm products as well. There is most definitly redundancy; which actually ENCOURAGES the lay public to watch tv, listen to the radio, or call their friends, and wait for the next, more 'urgent' statement. Are we trying to make the NWS 'indispensable' in this world of increasingly more popular 'private' weather companies? This would be at the cost of many lives, and though I don't put that past some entities of the government, probably NOT the NWS, however. The recent outbreak was the most deadly outbreak in recent history, I read. If this is true, then adding more products IS NOT HELPING!!!! Your idea, including this programming inside cell phones, automatically notifying people in the reduced and more specific 'polygons of death' is wonderfully simple and, I feel, would be more effective than issuing products on top of products that mean less and less to the general public. It doesn't sound like it would be difficult. We already have NWR's that alert people when urgent statements are issued in the appropriate area. And SAME (sp?) technology exists for the city emergency staff, police and fire departments, and media outlets. I believe this could be done, and I applaud you for blogging on this subject and offering up ideas; food for thought. Thank you for sparking off what I HOPE will be a conversation that helps effect changes in the way we help protect people, property, and the nation's economy. By the way, my thoughts and opinions are my own, and do not represent the opinions of the NWS, Alaska Region, or WSO Valdez (or even my own co-workers).

  3. Thanks for the comments Todd. I feel like in this particular situation there were many people who did not have or did not seek out adequate shelter. Many structures in the region do not have basements. I heard numerous stories of people taking shelter in their bathtub, which is better than nothing, but in these extremely destructive storms, does not necessarily prevent injury or death. So perhaps people were taking heed of warnings, but didn't do enough. Tornadoes are a difficult event because they are so spatially precise. One house can be totally demolished, while the one next door has little damage. This can lead to the issues with perceived over warning. It is also important to take the type of event into account. This event was extremely well covered by the media, and well warned by the NWS, however, it was an historic and record breaking event. Even though there was a large loss of life, doesn't mean that the NWS and emergency managers weren't doing their jobs well enough... this just may be an event like we've never seen before.

  4. Todd, this was an interesting post. We run into some of the same issues over here with notifications and over warning. I agree, the social side of warnings is pretty key. Issuing a warning makes no difference if it isn't understood or heeded.