October 1, 2021, is not only the start of a new month, it's also a 'first Friday' when Minnehaha County tests its warning sirens in the Sioux Falls area.

If you know what to look for, you can see the warning sirens strategically placed throughout Sioux Falls and in smaller communities around Minnehaha County. They are designed to warn people who are outside of impending danger such as a severe storm.

On the first Friday of each month, the county turns all its sirens in the Sioux Falls area. Just like clockwork, the sirens began their howl in Sioux Falls at 11 am sharp. They blared their one-note song for about one minute before winding down. The test will occur on the first Saturday at 11 am for the smaller towns in the county.

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The sirens are loud enough to be heard inside some buildings, even though they are not designed to do so. To receive warnings inside, it's recommended that people should purchase a weather radio and/or listen to their favorite Results-Townsquare station, like this one, for up-to-minute weather alerts.

As loud as the Minnehaha County sirens are, they pale in comparison to the loudest siren ever produced, the Chrysler Air Raid Siren. During the height of the Cold War, Chrysler built about 350 sirens and they were sold to communities to warn the public of an impending nuclear attack.

The 3 ton, 12-foot long siren was built on a shortened truck frame and powered by a V8 Hemi engine that produced 180 horsepower! The siren's output of 137db was nearly as loud as a 747 jet engine. The siren could cover a 16 square mile area where the average warning siren covers 4 square miles. That would definitely get your attention!

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