Not as often as I use to back in the 70's and 80's. Once every 2 to 3 months on the radio.
I wish just once theyd do a war of the worlds with that robot announcer voice. "New york and Paris have fallen to the invaders. Lock your doors and hide in the ba<x>sement."
it's supposed to be annoying, you're intended to notice it.
its usually around 11AM once a week where i live, don't really mind it<br />
but when theres an amber alert they play it non stop