It is the first Wednesday of the month, 1:00 pm, and the tornado sirens just went off. Eeriest damn sound.
Turns out they are tested every month at this time; Katharyn knew that right off the bat, when I asked.
The scenario put me in mind of a favorite scene from the 1991 Steve Martin movie LA Story, when the love interest from Great Britain asks what time of day would be appropriate for deep, sustained booming sounds. Martin’s character replies straight off: “Ah, deep sustained booming sounds. 9:00, 9:30 in the morning.” As if this were universal knowledge around LA.
Minnesota’s devices are officially called outdoor warning sirens, no longer “tornado sirens,” because their use has been generalized beyond storm warnings. When one sounds it might mean a chemical spill, nuclear accident, or flash flood. So don’t automatically run for the basement if you hear the siren.
Here is Hennepin County’s coverage map for county-owned sirens. If you are outdoors in one of the areas covered in red and they go off, you should hear it. (Indoors, all bets are off.)
The Star Tribune, at the 2008 link above, says that the coordinated system of sirens across the state came in in 1960 (in the “duck and cover” days), when the federal government installed them. Tornado sirens existed before, but the feds’ system brought the possibility of wider area coordination. In order to keep federal maintenance funds flowing, counties had to agree to a regime of monthly testing.
We didn’t have those back east, not anywhere I lived. Here the combination of occasional tornado weather and widespread farming, where people work outdoors, makes the outdoor warning sirens a fine idea indeed.
[Update 2015-08-05] My Facebook friends back in Massachusetts inform me that yesterday Groton had a full-on tornado warning. Everybody’s cell phones went off. There were multiple modalities of warning, including an audible siren, but no one knew what the latter was for! It goes off so infrequently there (or at least it did until global warming began messing up traditional weather patterns), and there is no monthly testing on the first Wednesday to accustom people to the sound.