Weather radio in the United States is a nationwide network of more than 1,000 transmitters that are run by the National Oceanic and Atmospheric Association, or NOAA. These stations broadcast weather conditions, forecasts and warnings produced by the National Weather Service 24 hours a day. Reception of these broadcasts requires a special radio capable of receiving transmissions in the VHF band. Seven frequencies are set aside for weather radio: 162.400, 162.425, 162.450, 162.475, 162.500, 162.525 and 162.550 MHz.
Each transmitter broadcasts weather information based on its location that is supplied by a local NWS office. The transmitter has a range of about 40 miles in optimum conditions; however, in many cases, reliable reception is less than that due to obstructions such as buildings, as well as geography. The NWS recommends that weather radio listeners place the radio in a location close to a window for the best reception.
Use tools provided by the NOAA and the NWS to select an appropriate frequency (link in Resources). Coverage maps are available for all 50 states, Puerto Rico, the Virgin Islands, Guam and American Samoa. Click on your location on the map, and then select an individual station from the state map. Some transmitters do overlap, so there is the possibility that more than one frequency will be available for any given location.
The NOAA broadcasts what are called "SAME tones" on weather radio frequencies to alert listeners visually to watches and warnings. A sub-audible tone sent with an alert activates the radio and displays the warning type on the screen. If your emergency radio supports this feature, first program the radio to the specific SAME code as per your receiver's instructions, and also to a station that sends SAME alerts for your location with clear reception (link in Resources).