National Weather Service United States Department of Commerce
NOAA Weather Radio
Transmitters in southeast Arizona
Tucson Safford Nogales
Call letters and frequency
WXL-30 (162.400 MHz) KXI-24 (162.550 MHz) WNG-703 (162.500 MHz)
Transmitter coverage maps
Tucson NOAA weather radio information Safford NOAA weather radio information Nogales NOAA weather radio information
Other NOAA Weather radio sites in Arizona (table)
(Other NOAA Weather radio sites in Arizona (map)
What is NOAA Weather Radio?

NOAA Weather Radio is a service of the National Oceanic and Atmospheric Administration (NOAA) of the United Stated Department of Commerce (DOC). As the "Voices of the National Weather Service," (NWS) it provides continuous broadcasts of the latest weather information from local National Weather Service offices. Weather messages are repeated every four to six minutes and are routinely updated every one to three 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 and those in agricultural areas provide information of interest to farmers. Other specialized information, such as hydrological forecasts and climatological data may be braodcast.

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 alerts 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.

In the most sophisticated alerting system, Weather Radio 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 (FCC).

Under a January 1975 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 and safety, both at a local and national level.

NOAA Weather Radio currenly 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. Thses frequencies are outside the normal AM or FM broadcast bands.

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, citizens band, and standard AM/FM radios as well as communications receivers, transceivers, scanners, and cable TV.

By nature and by 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.

NOAA Weather Radio is directly available to approximately 70 to 80 percent of the U.S. population. The National Weather Service is currenly engaged in a program to increse coverage to 95 percent of the population.

If you have a question regarding technical aspects of NOAA Weather Radio (such as reception and transmitter characteristics of a station) of are interested in becoming a partner with the National Weather Service in identifying or providing local funding and facilities for the installation of a Weather Radio transmitter, please contact your nearest National Weather Service office or the National Weather Service, Dissemination Systems Section (Attn:W/OSO153), 1325 East-West Highway, Silver Springs, MD 20910.

If you have a question regarding the weather information broadcast over NOAA Weather Radio, please contact the local National Weather Service office that does the programming for the station or the National Weather Service, Warning and Forecast Branch (Attn:W/OM11),1325 East-West Highway, Silver Springs, MD 20910.

NOAA Weather Radio operations in Tucson

The National Weather Service in Tucson operates three transmitters across southeast Arizona. This very high frequency radio operates on one of seven Megahertz channels, with an output radiated power of 100 watts. The studio equipment is located at the National Weather Service office in Tucson. One transmitter is located on Mt. Lemmon in the Santa Catalina Mountains. Call letters for this station are NOAA Weather Radio WXL-30. The second transmitter is located on Heliograph peak on Mt. Graham. The call letters for this station are NOAA Weather Radio KXI-24. The third transmitter is located on Crawford Hill near Nogales. The call letters for this station are NOAA Weather Radio WNG-703.

The antenna provides coverage over a large portion of southeast Arizona, transmitting out to distances of 50 to 100 miles. There is some reduction of reception in local areas, near hills and mountains, since the VHF radio propagation requires direct line of sight.

Programming on NOAA Weather Radio is oriented to the present and near future, with special emphasis on waarnings, advisories, and watches when necessary. The information broadcast is prepared and recorded in the National Weather Service office. with the information cycling every three to five minutes and updated as required. The broadcasts are transmitted continuously, 24 hours a day, seven days a week, including holidays.

The system is equipped with a "TONE ALERT" (alarm) device which is capable of delivering direct notice of warnings, including impending hazardous weather and hydrological conditions, to civil defense agencies, law enforcement authorities, the broadcast industry, and other institutions and individuals. This feature produces a single tone at 1050 hertz for three to five seconds which automatically turns on specially designed receivers within the transmitter's zone of coverage.

Individuals and organizations requiring frequent weather information should be able to satisfy most of their needs by obtaining a NOAA Weather Radio receiver. NOAA Weather Radio transmitters are located in or around most large communities in the United States.

What is the NOAA Weather Information line in Tucson?

On August 1, 1996, the National Weather Service in Tucson, Arizona began a new public weather information service. The service, called the NOAA Weather Information Line, will provide callers with current weather observations, short and long-term forecasts, and weather advisories and warnings.

The current weather information will include hourly observations from Tucson and Phoenix. It will also include such things as the high temperature, low temperature, and precipitation for Tucson. Regularly issued short-term (6 hour) forecasts for Tucson and the Santa Cruz Valley will be available twice a day, with more frequent issuances during significant weather events. During significant weather events, the short-term forecast will often cover a larger portion of southeast Arizona.

Weather advisories and warnings will be issued for significant and hazardous weather conditions affecting people in southeast Arizona. The Tucson National Weather Service Office is responsible for issuing advisories and warnings for Cochise, Graham, Greenlee, Pima, Southeast Pinal and Santa Cruz counties.

This weather information is available to callers through one of several phone lines which are connected to the Tucson National Weather Service NOAA Weather Radio broadcast system. However, the phone service will provide callers with only a part of the complete NOAA Weather Radio broadcast. In addition, those with weather radio receivers, especially those with radios equipped with an alarm, will be the first to receive urgent severe weather warnings. This will enable those with a weather radio to immediately take any necessary safety precautions.

Callers will be able to receive this up-to-date weather information on a 24-hour basis by calling 520-881-3333.