Take on the Flash Flood Warning

Last night at about 9:25pm, I was shocked when my phone started
buzzing like somebody had set off a fire alarm. I was driving so when
I finally got to a light, I saw it was some emergency alert for flood
warnings in "this area". Since it is so unspecific, you don't know
whether to be worried or not.

Before Snowden I may have asked how in hell anybody would know where I
am right now but that kind of innocence is long gone. I know of at
least two others who got the same message, one of whom was nowhere
near is house and also nowhere near me, so the real question is...did
be entire metropolitan area get bombarded with this, was it only
people with area codes like 917, 201, 718, 516 etc or was it sent to
people who were in the immediate vicinity?

For example, did a tourist from Indiana staying in midtown with his
260 area code get a beep?
Did a guy originally from Long Island now living in Houston get beeped
because he never got himself a new number?
How far out were these things sent?
How the hell do I get onto the do-not call list for this thing?