[Myrddin]

The National Weather Service runs a weekly test on various radio stations in my area. A set of preable tones is transmitted to "wake up" the emergency weather receivers. It can set off alarm tones too. A voice announcement (often just testing) follows. Another set of tones follows the announcement to shutdown the receiver.

We have thunderstorms in the area this week. The messages are the real thing. Warnings for hail up to 1.5 inches in diameter, flash floods, lightning and winds up to 70 MPH.

The old Emergency Broadcast System is now running in a "piggy back" form on top of NWS weather radio.

[BurbankKarl]

actually, the EBS is gone....it was replaced by the EAS. Emergency Alert System.

http://www.fcc.gov/eb/eas/

If you see a RHW code....run! (Radiological hazard)

http://eas.oes.ca.gov/Pages/easfaq.htm < frequently asked quesitons

[Domestic Church]

"The old Emergency Broadcast System is now running in a "piggy back" form on top of NWS weather radio."

I remember the old system well and know the NWS for the tornado reports, hurricane and winter storm alerts. This was a FEMA test broadcast.