Television and radio towers and satellites will broadcast a nationwide emergency test message next Wednesday. (Paul Sakuma/AP)

The familiar strains of the Emergency Alert System are heard at various times on television and radio stations across the country every week, usually to alert Americans of impending weather danger or missing children.

But the White House has the authority to active the system at the national level in the event of a major emergency including terrorist attacks or earthquakes.

In anticipation of future emergencies, television and radio stations and cable and satellite TV providers plan to broadcast the same emergency test message at the same time next Wednesday as part of the government’s first-ever nationwide test of the alert system.

The federal government began using the Emergency Broadcast System on radio and TV in 1963. Thirty years later, the Federal Communication Commission switched to the Emergency Alert System, which made it easier to spread the word across cable and satellite providers.

So how will the test work?

Next Wednesday at approximately 2 p.m. ET / 11 a.m. PT — while you’re settling in to watch a soap opera, game show or the latest “Real Housewives” episode — officials in Washington plan to transmit a national EAS message to radio and TV stations. In turn, the stations will broadcast the message over their air for up to three minutes, according to the FCC.

Audio of the message should sound exactly the same on radio and TV, but the on-screen images will vary depending on the channel.

In an effort to warn people in advance (seems ironic that they’re warning people about a test warning — but so be it), the FCC, the Federal Emergency Management Agency and the National Weather Service are encouraging broadcasters to run public service announcements about the nationwide test. (As a service, the National Association of Broadcasters is providing generic audio and video PSAs that stations may use.)

In the future, in an acknowledgement that most Americans are spending more time in front of smaller screens, federal, state and local agencies will be able to send emergency alerts to smart phones.

Already the FCC and FEMA are testing the new Personal Localized Alerting Network, or PLAN, in New York and Washington with the assistance of the nation’s major wireless providers.

Some day in the future, mobile and smartphone users will receive free, text-like messages that will flash across a telephone’s screen and trigger a special vibration. Once operational, participating federal, state and local agencies would be able to send information regarding only the most serious alerts — including major natural disasters or terrorist attacks.

Follow Ed O’Keefe on Twitter: @edatpost

Further reading:

FEMA, FCC launching new alert system early in D.C. and N.Y.

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