Weather radio

A weather radio service is a public broadcast service dedicated to airing continuous weather reports. In most locations, it requires a specially-designed radio capable of receiving "weather band" frequencies - when tuned to one of these channels, it receives a radio station that broadcasts both routine and emergency weather information. Some weather radio receivers are equipped with a standby alerting function - if the radio is off or tuned to another band and a severe weather bulletin is transmitted, it can automatically sound an alarm and/or switch to a pre-tuned weather channel for emergency weather information.

Weather radio services may also broadcast non-weather-related emergency information, such as in the event of a natural disaster, an AMBER alert or a terrorist attack. They generally broadcast in a pre-allocated very high frequency (VHF) range using FM. Usually a dedicated weather radio receiver or radio scanner is needed for listening, although in some locations a weather radio broadcast may be retransmitted on a conventional AM or FM frequency (as well as HD Radio substations), some terrestrial television stations broadcasting in MTS stereo transmit weather radio on their second audio program (SAP) channel as well as on one of its digital subchannels (where news and weather are applicable), on local public, educational, and government access (PEG) cable TV channels or during Emergency Alert System activations for tornado warnings primarily on cable systems.

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