NOAA Weather Radio (NWR) is an emergency broadcasting system operated by the U.S. National Oceanic and Atmospheric Administration (NOAA, pronounced NO-ah). The purpose of the network is to disseminate reports of weather conditions, forecasts, storm watches, and storm warnings. The NWR network is sometimes used to broadcast information concerning natural and human-made disasters such as earthquakes, volcanic eruptions, or wildfires. The system operates on a continuous basis.
In order to receive NWR broadcasts, a special, battery-powered wireless receiver is necessary. The receiver is normally silent, but when dangerous conditions occur, a loud alarm sounds. The alarm signal is followed by a voice transmission describing the nature of the event and the regions threatened by it. The transmissions are made on various channels in the very-high-frequency (VHF) portion of the radio spectrum.
Some officials have proposed that NWR should be used to broadcast non-environmental warnings, such as news of terrorist threats or attacks. As of this writing, no such implementation has been made.