Via both Twitter and email, I have been asked to comment about two separate siren controversies, one involving sirens being sounded and the second involving sirens not being sounded. Because there are multiple issues involving politics and personnel, I don't feel comfortable specifically commenting on either controversy.
Sirens are an important part of the warning system. Less-than-optimal siren procedures were a factor in the extremely high loss of life in Joplin. So, please allow me to offer general some thoughts to communities struggling with siren procedures.
- Sirens should be considered outdoor warning systems (only).
- Sirens should be sounded for tornado warnings.
- I am opposed to sirens being sounded for severe thunderstorm warnings with one possible exception and that is when the winds are explicitly forecast to exceed 85 mph (equivalent to lower EF-1 tornado intensity).
- Sirens in tsunami and flash flood areas are appropriate but should be used with care (we don't want people headed for the basement when floods are approaching).
- Sirens should never be used for "all-clear" purposes. More confusion potential.
- Sirens should only be sounded in the area actually threatened! Sounding them over entire counties when a fraction of the county is threatened creates "siren fatigue" which, over time, also threatens lives.
Whatever policy you adopt, it must be well-publicized so citizens know what to respect and how to respond. Do not deviate from the policy ("we'll sound them for a severe thunderstorm just this one time") or you just create confusion. Social science clearly shows that confusion is the enemy of effective action in dangerous situations.
There is a lot of information about sirens and the Joplin tornado in my book, When the Sirens Were Silent. It is sold out of the paper version but is available in ebook form here. The price is $2.99 for the ebook.