Whelens, Thunderbolts, and South Korean electronic sirens

[ver tum]

Whelens and dual tone Thunderbolts for a tornado warning:
http://youtube.com/watch?v=Xhc5Jei1GqM

Whelens in the distance for another tornado warning:
http://youtube.com/watch?v=4X0ETEWfl6s

Unknown electronic sirens in Busan, South Korea for a Civil Defense drill:
http://youtube.com/watch?v=aNlJR7F6frQ