Carolina Curious: Why Are Weather Alerts Sometimes Hard To Understand?

Carolina Curious: Why Are Weather Alerts Sometimes Hard To Understand?

7:00am Sep 12, 2018
The antenna tower outside of WFDD studios. EDDIE GARCIA/WFDD

One of the services that radio stations like WFDD provide is broadcasting alerts from the National Weather Service. These emergency alerts let listeners know about weather concerns, helping folks stay safe. With Hurricane Florence being on track to hit the East Coast this week, and a state of emergency in place in North Carolina, these types of messages are important.

And many times, those announcements are clear. But sometimes, those messages are clear as mud. You may have heard one that was a little noisy, or distorted, and felt frustrated that you couldn’t decipher it.

Listener Howard Covington shares your concern.

He asks, “Why in an era of broadcasting advances can't the weather service produce an alert that can be easily understood?”

Covington feels that with modern technology, we should hear crisp audio.

“Here you have a government agency whose mission is to alert people of imminent dangers, and the one thing they're supposed to do isn’t being done very well, because the message is garbled,” says Covington.

So what kind of technology is used for sending weather alerts?

George Newman, the chief operator and operations manager at WFDD, spends much of his time troubleshooting the equipment at the station. That includes making sure our Emergency Alert Services, or EAS machine, is functioning properly.

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The Sage Digital ENDEC is used to receive and send all types of alerts, including those from the National Weather Service. EDDIE GARCIA/WFDD

Ours is a blue box called a Sage Digital ENDEC. Newman says it’s an encoder and decoder that brings in all the systems WFDD is required to monitor.

“You can hear it's clear, but there’s some static in the background,” says Newman. “National Weather Service alerts are consistent because they’re coming from the same place.”

So how are these alerts made?

The alerts are composed on a custom workstation called WarnGen. And though there have been updates, it has been in use since the late 1990s.

Nick Petro works for the National Weather Service in Raleigh. He’s their warning coordination meteorologist. That means he’s a liaison between the teams that get weather info out to the public.

“So what happens then is once the alert is created it goes across our internal network,” Petro says. “It creates the audio, and it uses a voice synthesizer to create the actual warning. And then it gets pushed out through our software that manages the NOAA weather radio broadcast.”

A voice synthesizer – so what we’re hearing is a synthetic interpretation of a human voice.  What could affect the sound quality of this weatherperson simulation? Petro says there are a number of variables.

“That audio signal is sent over telephone lines,” he says. “There’s one point of entry for maybe signal degradation or static to enter the stream.”

Were talking landlines here. Yes, the kind that once upon a time we relied on for a phone call. That telephone line leads to a transmitter that sends the message into the air.

Petro says that’s “another entry point for static or signal degradation to get in the system."

"A lot of times the weather or atmospheric conditions can affect the way radio waves propagate and alter or introduce static into an audio stream.”

So if this system of sending and receiving is so potentially noisy, why is it still being done this way? Are any changes in the works?

“That, I would say, would probably take some effort,” Petro says. “And I don’t know what it would take. I don’t know what the cost involved would be. I don’t know if there are any efforts to do any upgrades. But certainly, the system that we have in place now is the system that we have. If there is a solution to make it better out there, I’m not really sure what that is, or how, or when any such improvements could be deployed.”

That’s one of the reasons Petro urges you to look into backup methods, like a NOAA weather radio, or apps, such as Ready NC, Weather Underground, NOAA Weather Radar, or Hurricane Tracker. And with a major storm on the way, a battery-powered portable radio can be very helpful for getting up to the minute alerts. For more ideas on being prepared for disasters, check out Ready.gov.  And stay safe out there.

 

 

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