Weatheradio
|
|
NOAA_weather_radio_logo.gif
Weatheradio is a special radio service available over much of North America that transmits weather warnings and forecasts 24 hours a day. Hundreds of stations are operated in the U.S. (where it is more commonly called NOAA Weather Radio (NWR)) by the National Weather Service of NOAA, and in Canada by the Meteorological Service of Canada, under Environment Canada. Each radio station is programmed from a local or regional NWS or MSC office. One station is also available in Bermuda, operated by the Bermuda Weather Service.
Most stations broadcast on a special VHF frequency band at 162 MHz, which has seven narrowband FM channels. The original frequency was 162.550, with 162.400 and 162.475 being added later. In recent years, the proliferation of stations meant to make sure everyone has access to warnings has pushed that number to seven, now including the "intermediate" channels of 162.425, 162.450, 162.500, and 162.525 MHz. These channels (often numbered in that order) are receivable on special weatheradio receivers, available across both countries by mail-order and at some retailers such as Radio Shack, and on most marine VHF radio transceivers. In addition, many consumer electronics, such as two-way radios, are now being sold with the ability to receive weatheradio broadcasts. Some stations in Canada also broadcast on regular FM and AM broadcast stations.
When a weather warning is issued for the area which a station covers, certain weatheradios are designed to turn on or sound an alarm upon detection of a 1050 Hz tone, issued for ten seconds immediately before the warning message. In the U.S., newer radios can instead detect a digital-over-audio protocol called Specific Area Message Encoding or SAME, which allows the radio to limit alarms to only certain warnings, and only to the actual section of the broadcast area which the listener is located. (This system later became the Emergency Alert System now required by the FCC for broadcast stations.) In Canada, many stations operate Weathercopy, which is a higher-speed version that can actually transmit entire text forecasts and warnings, but is not designed for alerting.
NOAA_weather_radio_map.jpg
The bulk of programming however is still in regular voice rather than digital, with a forecaster recording each message once and a system having it repeat in a loop. In the U.S., the NWS has now installed a console replacement system (CRS) which uses a synthesized voice to read text announcements. The voices have recently been upgraded with new software that gives a much more realistic and pleasant male (named "Alex") or female voice (named "Donna"), and also allows intonation so that the tone of voice changes with the urgency of the message being read. They supplanted a more primitive male voice called "Perfect Paul" which had been nicknamed "Igor", "Sven", and "Arnold", among others, for its mechanically awkward pronunciation and intonation (another voice, "Huge Harry" was also used). "Paul" and "Harry" can still occasionally be heard on some stations, for example giving station identification.
Many stations also broadcast in other local languages, including both French and English in Ottawa/Gatineau, Montréal, and the city of Québec; French only in other parts of the province of Québec, and synthesized in both English and Spanish in Puerto Rico.
See also: Navtex
External links
- U.S. NOAA/NWS Weatheradio page (http://www.nws.noaa.gov/nwr)
- Canada EC/MSC Weatheradio page (http://www.msc.ec.gc.ca/msb/weatheradio//index_e.cfm)
- Bermuda Weather Service (http://www.bermudaweather.bm/bws/)
- http://www.weatherradio.info