Weather radio


A weather radio is a specialized radio receiver that is designed to receive a public broadcast service, typically from government-owned radio stations, dedicated to airing weather reports on a continual basis, with the routine weather reports being interrupted by emergency weather reports whenever needed. Weather radios are typically equipped with a standby alerting function—if the radio is muted 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, a child abduction alert, or a terrorist attack. They generally broadcast in a pre-allocated very high frequency range using FM. Usually a radio scanner or a dedicated weather radio receiver is needed for listening, although in some locations a weather radio broadcast may be re-transmitted on an AM or FM broadcast station, on terrestrial television stations, or local public, educational, and government access cable TV channels or during weather or other emergencies.

Weather radio receivers

Weather radios are generally sold in two varieties: home or portable use. Portable models commonly offer specialized features that make them more useful in case of an emergency. Some models use crank power, in addition to mains electricity and batteries, in case of a power outage.
Smaller hand-held weather receivers generally do not support the SAME alert type encoding, but allow hikers and other explorers to listen to weather reports without packing a heavy and bulky base station radio. Some models have a built-in flashlight and can double as a cellphone charger. Some also serve as a more general emergency radio and may include multiband and two-way communication capability. "Scanner" radios designed to continuously monitor the VHF-FM public service band are already able to receive weather channels.
Besides SAME alerting capability, modern weather radio receivers, especially those that are compliant with CTA standard 2009-B, may include visual alerting elements and allow for the use of external devices to alert those who are deaf or hearing impaired.

Global weather radio services

Both private and commercial seagoing vessels need accurate weather reports, in order to avoid storms that might damage or capsize the vessel, or make paying passengers uncomfortable. One such service is Navtex, which is a low-frequency facsimile radio service.

North American weather radio services

The United States' NOAA, Canada's Weatheradio, Mexico's SARMEX and Bermuda operate their government weather radio stations on the same marine VHF radio band, using FM transmitters, and the same seven frequencies as NOAA Weather Radio. Bermuda only uses 162.550 and 162.400. NWR transmitters operate VHF-FM between 5–1000 watts. NWR channels operating in the range of 162.3625-162.5875 MHz have a band spacing of band spacing of 25 kHz may have bandwidths up to 16 kHz. The original "weather" frequency was 162.550 MHz, with 163.275 MHz initially recommended as a backup and later dropped due to interference problems with other federal agencies.
NOAA Weather Radio, Weatheradio and SARMEX all refer to the seven stations by their frequencies:
162.400, 162.425, 162.450, 162.475, 162.500, 162.525 and 162.550 MHz.
Other channel designations such as WX1 through WX7 "have no special significance but are often designated this way in consumer equipment" and "other channel numbering schemes are also prevalent/possible" according to NOAA and USCG. Ordering channels by when they were established is "becoming less 'popular' over time than a numerical ordering of channels." Weather radios may list stations in the order of their WX#, or by a "Preset Channel" number 1 thru 7 in ascending frequency order.
The "WX#" format is continued from WX8 up to WX12 on some lists and radios to include 163.275 MHz and or one or more of the Canadian continuous marine broadcast frequencies 161.650, 161.775, 161.750, 162.000. Unlike WX1-WX7 typically ordered by frequency adoption by NWS, there is no consistent frequency inclusion nor assignment for WX8-WX12. Effective January 1, 2019, channels 2027 and 2028 are designated as ASM 1 and ASM 2 respectively for application specific messages as described in Recommendation ITU-R M.2092. 163.275 MHz was formerly used by the NWS for coordination during power outages.
All stations in United States, Canada, and Bermuda transmit a :File:1050Hz Tone.ogg|1050 Hz attention tone immediately before issuing a watch or warning, and this alone serves to activate the alarm feature on many older or basic alerting radios.
All U.S. and newer Canadian stations transmit WRSAME codes a few seconds before the 1050 Hz attention tone that allow more advanced receivers to respond only for certain warnings that carry a specific code for the local area. SAME codes are defined for counties, parishes, territories, or marine zones, and are set using preassigned six-digit FIPS county codes or CLC codes. The SAME code protocol also includes an end-of-message tone (three short data bursts of the binary 10101011 calibration then "NNNN", which some radios will use to mute the speaker after the alert broadcast has been completed.

United States

NOAA Weather Radio is an automated 24-hour network of more than 1000 radio stations in the United States that broadcast weather information directly from a nearby National Weather Service office. A complete broadcast cycle lasts about 3 to 8 minutes long, featuring weather forecasts and local observations, but is interrupted when severe weather advisories, warnings, or watches are issued. It occasionally broadcasts other non-weather related events such as national security statements, natural disaster information, environmental and public safety statements sourced from the Federal Communications Commission's Emergency Alert System. Weather Underground discontinued live streams of NWR broadcasts in 2017.

Canada

In Canada, Weatheradio Canada transmits in both official languages from 230 sites across Canada. Canadian broadcasts are also transmitted on travelers' information stations on AM and FM, especially near national parks.

Caribbean

Bermuda Radio is a weather radio station in Bermuda working under the Government of Bermuda.
Bermuda has only one station dedicated purely for weather, on 162.55 MHz from Hamilton, now operated by the Bermuda Weather Service with tropical weather forecasts from NOAA. It has a second station, however, for marine conditions and forecasts, ZBR, at 162.4 MHz.

Mexico

Mexico has since launched its own weather radio system, SARMEX for coverage of its cities, which also implements the Mexican Seismic Warning System. Some Mexican alert radios also support activation by a two-tone alert for another type of risk warning.

European weather radio services

Germany

In Germany, the Deutscher Wetterdienst broadcasts marine weather reports and weather warnings via long and short wave transmissions.

Commercial weather radio services

The weather radio band is part of the marine VHF radio band reserved for governmental services. However, most standard AM and FM broadcast radio stations provide some sort of private weather forecasting, either through relaying public-domain National Weather Service forecasts, partnering with a meteorologist from a local television station, affiliating with a commercial weather service company, or copying a commercial service's public forecasts without payment or permission.
Accuweather and The Weather Channel both operate large national weather radio networks through standard AM and FM stations. Brookstone licensed Accuweather's data service for their popular 5 Day Wireless Weather Watcher Cast Forecaster.
Microsoft's MSN Direct was a popular data service that included weather forecasting sent over US FM radio signals from 2004 to 2012. It was used by Microsoft Spot watches and Oregon Scientific clocks.