“Warning Desensitization” Makes SKYWARN Spotters even more Important

As I wrote earlier, I attended a severe weather symposium March 2, the same day that southern Indiana got slammed by tornadoes. In this post, I’ll share a little more about that conference.
It was the 16th Annual Sever Weather Symposium, organized and hosted by The Ohio State University’s Meteorology Club. This was not storm spotter training or even advanced spotter training. But any spotter who is interested in learning more about severe weather would do well to attend future instances of this symposium.
I was particularly interested in a presentation by Gary Garnet, warning coordination meteorologist, National Weather Service Cleveland, Ohio weather forecast office. Garnet spoke on “Findings from the Joplin Tornado Assessment.” His presentation about the devastating tornado strike in Joplin, Missouri on May 22, 2011 did not focus on meteorology. Rather, he reported on a study he helped to conduct to assess “issues ranging from internal NWS warning operations to dissemination strategies to public warning response.” Garnet and other team members had conducted nearly 100 interviews in Joplin with tornado survivors, business people, media representatives as well as emergency management, NWS and local government officials. The team’s full report is available on the Web.

Tornado warnings issued before and during the Joplin tornado. Notice how some of the warning polygons overlap. Graphic courtesy NWS.
Garnet reported that due to warning desensitization, most Joplin residents did not take immediate action when they learned of the NWS tornado warning. Instead, most sought additional information, including going outside to look for the storm, eating away at the 21 minutes between the warning and the beginning of EF-4 tornado damage.

Garnet said “non-routine triggers” are what eventually prompted citizens to take action to protect themselves. For example, Joplin officials broke from their normal practice and sounded tornado sirens more than once. Broadcasters began imploring listeners to “take cover now,” something listeners were not accustomed to hearing.
In some ways, the weather service’s relatively new practice of basing warning areas on storm movement, rather than county lines, adds to the problem. Making warning areas more specific is a good idea but NOAA weather radio still alerts entire counties and many (if not most) tornado siren systems lack the ability to selectively activate sirens. In addition, subsequent warning polygons often overlap each other, confusing citizens.
So, what does all this have to do with ham radio? To me, it reinforces the importance of live reports from trained spotters. The earlier a spotter makes a report, the earlier NWS can issue a warning and the more time citizens have to decide whether they are at risk. Also, when a ham sees a tornado and reports it via radio, a lot of people hear it: other hams, NWS meteorologists, broadcasters and members of the general public who listen to spotter nets on their scanners. Such reports can provide the non-routine triggers that get people to take cover.