Someone hacked every tornado siren in Dallas. It was loud.
Last year, someone kept hacking into traffic signs in Dallas — corrupting bland electronic messages into jokey missives such as: “Work is Canceled — Go Back Home” and “Donald Trump Is A Shapeshifting Lizard!!”
Funny? Dumb? Vandalism? Whatever your opinion of the pranks, the big Dallas hack of 2016 had one quality totally lacking in this year’s sequel: It was silent.
On Friday night, 18 minutes before midnight, every single one of Dallas’s 156 emergency weather sirens started doing this:
https://twitter.com/deadlyblonde/status/850576467234869248/video/1
The sirens, whose purpose is to be heard by anyone caught outdoors in a tornado or dangerous storm, screamed from the southern reaches of Oak Cliff to newspaper columnist Robert Wilonsky’s house in the north. They blared for an hour and a half, to the annoyance, terror or amusement of 1.3 million residents.
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Source and more: https://www.washingtonpost.com/news/the-intersect/wp/2017/04/09/someone-hacked-every-tornado-siren-in-dallas-it-was-loud/

Last year, someone kept hacking into traffic signs in Dallas — corrupting bland electronic messages into jokey missives such as: “Work is Canceled — Go Back Home” and “Donald Trump Is A Shapeshifting Lizard!!”
Funny? Dumb? Vandalism? Whatever your opinion of the pranks, the big Dallas hack of 2016 had one quality totally lacking in this year’s sequel: It was silent.
On Friday night, 18 minutes before midnight, every single one of Dallas’s 156 emergency weather sirens started doing this:
https://twitter.com/deadlyblonde/status/850576467234869248/video/1
The sirens, whose purpose is to be heard by anyone caught outdoors in a tornado or dangerous storm, screamed from the southern reaches of Oak Cliff to newspaper columnist Robert Wilonsky’s house in the north. They blared for an hour and a half, to the annoyance, terror or amusement of 1.3 million residents.

Source and more: https://www.washingtonpost.com/news/the-intersect/wp/2017/04/09/someone-hacked-every-tornado-siren-in-dallas-it-was-loud/