Information about the NOAA Weather Radio Broadcast
NOAA Weather Radio is a service of the National Oceanic and Atmospheric Administration (NOAA) of the U.S. Department of Commerce. As the "Voice of the National Weather Service," it provides continuous broadcasts of the latest weather information from local National Weather Service offices. Weather messages are repeated every 4 to 6 minutes and are routinely updated every 1 to 3 hours or more frequently in rapidly changing local weather or if a nearby hazardous environmental condition exists. Most stations operate 24 hours daily.
The regular broadcasts are specifically tailored to weather information needs of the people within the service area of the transmitter. For example. in addition to general weather information, stations in coastal areas provide information of interest to mariners. Other specialized information, such as hydrological forecasts and climatological data, may be broadcasted.
During severe weather, National Weather Service forecasters can interrupt the routine weather broadcasts and insert special warning messages concerning imminent threats to life and property. The forecaster can also add special signals to warnings that trigger "alerting" features of specially equipped receivers. In the simplest case, this signal activates audible or visual alarms, indicating that an emergency condition exists within the broadcast areas of the station being monitored and alters the listener to turn up the volume and stay tuned for more information. More sophisticated receivers are automatically turned on and set to an audible volume when an alert is received. A routine weekly test of the warning alarm is normally conducted each Wednesday between 11 AM and noon. If there is a threat of severe weather, it will be postponed until the next available good weather day.
In the most sophisticated weather radio alerting system, Specific Area Message Encoding (SAME) digital coding is employed to activate only those special receivers programmed for specific emergency conditions in a specific area, typically a county. SAME can activate specially equipped radio and cable television receivers and provide a short text message that identifies the location and type of emergency. SAME will be the primary activator for the new Emergency Alert System planned by the Federal Communication Commission.
NOAA Weather Radio is directly available to approximately 70 to 80 percent of the U.S. population. The National Weather Service is currently engaged in a program to increase coverage to 95 percent of the population. Under a January 1995 White House policy statement, NOAA Weather Radio was designated the sole Government-operated radio system to provide direct warnings into private homes for both natural disasters and nuclear attack. This concept is being expanded to include warnings for all hazardous conditions that pose a threat to life or property, both at a local and national level.
NOAA Weather radio currently broadcasts from 400 FM transmitters on seven frequencies in the VHF band, ranging from 162.400 to 162.550 megahertz (MHz) in fifty states, Puerto Rico, the Virgin Islands, Guam, and Saipan. Unfortunately, these frequencies are outside of the normal AM or FM broadcast bands. The Voice of the National Weather Service broadcasts continuous weather information 24 hours a day across the nation on the following frequencies: 162.400 MHz, 162.425 MHz, 162.450 MHz, 162.475 MHz, 162.500 MHz, 162.525 MHz, 162.550 MHz.
Special radios that receive only NOAA Weather Radio, both with and without special alerting features, are available from several manufacturers. In addition, other manufacturers are including NOAA Weather Radio as special features on an increasing variety of receivers. NOAA Weather Radio capability is currently available on some automobile, aircraft, marine, citizen-band, and standard AM/FM radios as well as communications receivers, transceivers, scanners, and cable TV.
By nature and design, NOAA Weather Radio coverage is limited to an area within 40 miles of the transmitter. The quality of what is heard is dictated by the distance from the transmitter, local terrain, and the quality and location of the receiver. In general, those on flat terrain or at sea, using a high quality receiver, can expect reliable reception far beyond 40 miles. Those living in cities surrounded by large buildings and those in mountain valleys with standard receivers may experience little or no reception at considerably less than 40 miles. If possible, a receiver should be tested in the location where it will be used prior to purchase.