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wrsima01.jpgIt’s hurricane season again, and whether you’re on the coast or inland, you’re likely to see the effects of these storms first-hand.  With that in mind, we’ve prepared a three-part series to help you get a grip on the tools that can help you weather the storm.

A month or so ago we had a close call here in North Texas with a spate of tornadoes that killed five people and destroyed a good bit of property.  While we escaped unharmed, the scary part was that the tornadoes came in the middle of the night; two of the people killed were an elderly couple who didn’t wake up until the storm hit.

To prepare for a storm, you first have to know it’s coming.  If you’re like us, the last time you heard about “alert” weather radios was back when they went off way too often — pretty much any time the weather station you’d tuned to issued a message — and eventually ended up turned off or stowed away.  Thankfully, technology has come a long way since then, and through the use of digital signals you can now receive timely, accurate alerts that actually apply to you. 

In part one of this series, we bring you up to speed on weather radios — and their new, high-tech cousins “public alert devices” — and give you an idea of how to select the best one for your situation.  (Lots more after the jump.)

NOAA Weather Radio 

For decades, NOAA (the National Oceanic & Atmospheric Administration) has been broadcasting general weather information and alerts on the “Voice of NOAA’s National Weather Service” commonly known as “NOAA Weather Radio” (NWR).  NWR broadcasts on seven VHF frequencies (up from the original three):

  1. 162.400
  2. 162.425
  3. 162.450
  4. 162.475
  5. 162.500
  6. 162.525
  7. 162.550

Most metropolitan areas are covered by one or more of these frequencies, though in more rural areas special antennas may be required for good reception. 

Though NWR has broadcast mostly the same information over the years, technology has improved the timeliness and quality of the broadcasts.  In the 1990s, NWR switched to automated (read: computer) voice broadcasts, which enabled them to tie NWR more directly in to their improving weather data systems.  In 2002, NWR added two new “more human sounding and understandable” voices to their automated system.  They even have names: Donna and Craig.

However, the most significant advances in NWR service have come through the addition of digital data to the broadcasts.

SAME Coding

wrsima02.jpgThe National Weather Service (NWS) began officially experimenting with adding digital codes to their broadcasts in the mid 1980s in order to “identify messages concerning life threatening or property damaging events,” and that experimentation grew into what is now called the Specific Area Message Encoding (SAME) system.  According to NOAA:

Previously, NWS have been using a similar digital approach on its text dissemination services, called the Universal Geographic Code (UGC), with great success.  UGC is a geographic and “product expiration” code used in most event-driven and regularly scheduled NWS text products regardless of text dissemination method.  SAME is currently an audio only dissemination protocol used on event-driven products directly related to NWS mission of protection of life and property.

So, SAME is essentially a system of digitally encoding the type of alert, the county(ies) affected, and the alert’s expiration time directly into the NWR voice broadcasts.  (NOAA reports that you may actually be able to hear the SAME encoding as a “very brief static burst” depending on the characteristics of your receiver.)

By checking the counties covered in the watch or warning against the counties you’ve specified are within your “area of interest,” modern weather radios use SAME to alert you only when the alert event applies to you. 

Public Alert Receivers

wrsima03.jpgIn 2003, the Consumer Electronics Association (CEA) took the next step in enabling home use of the SAME system by establishing a commercial standard for “Public Alert Receivers” which can receive and differentiate NWR-broadcasted SAME alerts for a wide variety of weather conditions including: blizzards, coastal floods, dust storms, flash floods, floods, high winds, hurricanes, severe thunderstorms, tropical storms, tsunamis, winter storms, and, yes, tornadoes.  They can also receive a group of national codes which are required for all FCC-regulated broadcast stations.  These include emergency action notifications (and terminations); national information center releases; and periodic, monthly, and weekly test activations.

Interestingly, the SAME/CEA standards also including a listing of state and local codes which are optionally broadcast.  These includes alerts for avalanches, child abductions, civil dangers and emergencies, earthquakes, evacuations, fires, hazardous materials, law enforcement events, local area emergencies, 911 outages, volcanoes, shelter-in-place warnings, and even nuclear power plant and radiological hazard warnings.

The true usefulness of CEA-type Public Alert Receivers lies in the fact that, unlike old weather “alert” radios which rang an alarm whenever they received a watch or warning of any type from the NWR station they monitored, Public Alert Receivers check the broadcast’s SAME encoding and only alert you to the events occurring within the NOAA-defined location code for your county (or sub-county area).  Many devices go one step further in allowing you to specify the type of alert (warning tone, audio, and/or visual) for each event type.

The Emergency Alert System (EAS)

You’ve probably heard of the Emergency Broadcast System (EBS), which used to exist as a network in which TV and radio station were required to participate.  Every so often you’d hear that special tone on AM and FM radio stations indicating that they were doing an EBS test.  In 1996, EBS was replaced with the Emergency Alert System (EAS). 

The EAS improves upon the old EBS system by offering a digital encoding scheme similar to, but simpler than, the SAME system.  It’s important to note that not all AM/FM radio stations participate in EAS.

Read on to page 2 for common features and more.

pages: 1 2 3

 

One Response to Hurricane Preparedness Part 1: Weather Radios/Public Alert Devices

  1. Bill Fargo says:

    While waiting fo the testing and reviews, the list of providers could have contained more discrimination as to features and capabilities.
    I’m not interested enough to scroll and poke through their websites.

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