NOAA Weather Radio All Hazards
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NOAA All Hazards Weather Radio is a network of radio stations broadcasting continuous weather information directly from a nearby National Weather Service (NWS) office. It is operated by the NWS, an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United States Department of Commerce. NWR broadcasts National Weather Service warnings, watches, forecasts and other hazard information 24 hours a day. It also broadcasts alerts of non-weather emergencies such as national security, natural, environmental, and public safety (see: AMBER Alert) through the Federal Communications Commission's (FCC) Emergency Alert System.
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[edit] Operations
Known as the Voice of NOAA's National Weather Service, NWR is provided as a public service by the NOAA. NWR includes more than 940 transmitters [1], covering all 50 U.S. states, adjacent coastal waters, Puerto Rico, the U.S. Virgin Islands, Guam, American Samoa and Saipan. NWR requires a special radio receiver or scanner capable of receiving the signal.
The radio service transmits weather warnings and forecasts 24 hours a day. In addition to weather information, NWR works in cooperation with the FCC Emergency Alert System, providing comprehensive weather and emergency information. In conjunction with federal, state, and local emergency managers and other public officials, NWR also broadcasts warning and post-event information for all types of hazards, including natural (such as earthquakes or avalanches), environmental (such as chemical releases or oil spills), and public safety (such as AMBER alerts or 911 Telephone outages).
Many television stations which broadcast in MTS stereo and have the capability (both commercial and public), will also air their local feed of NWR on their second audio program channel if they aren't carrying a program which features either a Spanish language translation or a Descriptive Video Service track for the visually impaired. Some digital subchannels which carry weather information may also have NWR airing in the background.
Hundreds of stations are operated in the United States (where it is more commonly called NOAA Weather Radio, or NWR) by the National Weather Service of NOAA, and in Canada by the Meteorological Service of Canada (where it is called Weatheradio 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. [2]
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 weather radio receivers, available by mail-order and at some retailers, on most marine VHF radio transceivers, Amateur radios, and on scanners. These "weather radios" are available for prices ranging from US$35 and up. In addition, many consumer electronics, such as two-way radios and CB radios, are now being sold with the ability to receive weather radio broadcasts. Some stations in Canada also broadcast on regular broadcasting band FM and AM broadcast frequencies. The limited Australian service is broadcast on the LW band.
In the USA, there are two different channel numbering systems used: The first is the chronological sequence that the radio frequencies were allocated to the service: 1=162.550, 2=162.400, 3=162.475, 4=162.425, 5=162.450, 6=162.500, 7=162.525. The second is in simple increasing radio frequency sequence: 1=162.400, 2=162.425, 3=162.450, 4=162.475, 5=162.500, 6=162.525, 7=162.550. Both are in use in various documentation, both are correct, yet totally different, so if you are going to help someone program a new weather receiver it's best to tell them the frequency to use instead of the channel number.
As of late 2006 there are more than 900 NWS transmitters covering 95% of US population. Depending on your location you may receive weather broadcasts on more than one of the seven channels. There can be situations where the one with the best signal might not be the one broadcasting information for your location. You can either monitor both channels for a while and figure out what regions they are covering, or you can contact the NWS to find out which frequency they are using to broadcast information for your location. These offices are usually listed in the telephone book under “US Government, Department of Commerce.”
[edit] Alerting
When a weather warning is issued for the area which a station covers, certain weather radios 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. The specification calls for the NWS transmitter to send the 1050 Hz tone for 10 seconds, and the receiver to decode it within 5 seconds (any extra tone time over and above the decode time is considered as part of the alerting mechanism). This system simply turns on the audio of every muted receiver within the radio horizon of the transmitter (i.e. any receiver within the transmitters "footprint").
Newer radios can instead detect a digital-over-audio protocol called Specific Area Message Encoding or SAME, which allows the users to program their radios for specific geographical areas of interest and concern, rather than for an entire regional broadcast area. The SAME code is broadcast, followed by the 1050 Hz tone. The beauty of the SAME codes is that they eliminate the numerous "false alarms" for the 1050 Hz weather alerts that may apply to an area 100 or 150 miles distant. The SAME codes are mostly aligned along county lines using the standard US Government FIPS county codes. Most modern SAME equipped radios can be programmed to receive alerts for more than one FIPS code if the user is located along a county boundary.
Once the SAME receivers are programmed they will limit alarms to only certain warnings, and only to the actual section of the broadcast area which the listener is located prior to the broadcast of the 1050 Hz tone. Some receivers allow you to program in several codes so you can include the areas surrounding your location. For example, if your area has frequent storm warnings, and the storms usually come from the east, you can program your receiver for the code for your area, plus the code for the area to the east. (This notification system was later adopted by the Emergency Alert System—the replacement for the earlier Emergency Broadcast System and even earlier CONELRAD) now required by the FCC for broadcast stations.
In Canada, stations will officially be implementing SAME in May 2007. Many Canadian stations also used to operate Weathercopy, which was a data stream that transmitted entire text forecasts and warnings, but was not designed for alerting. This system was decommissioned in 2003 because of new technologies such as the internet and satellite.
[edit] NOAA Weather Radio All Hazards Programming
"Typical National Weather Service Forecast"
[edit] Routine Forecast Products
The NOAA Weather Radio All Hazards network has a multi-tier concept for forecasting or alerting the public to all types of weather. Actual products vary by the area that the transmitter serves. The main public forecast products typically played during the day's program cycle are:
[edit] Hourly Observations
A typical hourly observation report updated twice hourly at the top of the hour and at eleven minutes past the hour heard over NOAA Weather Radio stations features the following:
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- A complete detail of the current sky condition, temperature, dew point, humidity, wind speed/direction and barometric pressure for the main reporting station in that station's city of license. If the main reporting station's information is unavailable, the nearest reporting station to that area is played first instead, in which case that area's observations will not be repeated at the end of the observation product.
Example from KWN-41 Shubert, Nebraska: "At 8 AM in Falls City, it was sunny. The temperature was 60 degrees, the dewpoint 59, and the relative humidity 97%. The wind was west at 6 miles an hour. The pressure was 30.00 inches and steady." In some locales, in the event the main reporting weather station had missing data, or no data available, the following message would thus be played (example from KWO-37 Los Angeles): The report from Downtown Los Angeles was not available.
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- Details on the sky condition, temperature and wind speed/direction (sometimes including information on dew point, humidity and pressure) within 50-75 miles of the Weather Forecast Office and main reporting station.
Example from KWN-41: "Across eastern Nebraska, southwest Iowa, and northwest Missouri, skies ranged from sunny to mostly sunny. It was 60 at Beatrice, 59 at Lincoln, 59 at Nebraska City, 57 at Omaha, 59 at Red Oak, and 62 at St. Joseph." Some cities would round up only sky conditions if temperatures in all reporting stations were within 5 degrees of each other. An example: skies ranged from sunny to mostly sunny, and temperatures were between 57 and 62 degrees.
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- Information on sky condition and temperature (and on certain stations, including wind speed/direction) within 250 miles of the WFO area of responsibility.
Example from KWN-41: "Here are some observations from around the region. Fog was reported with a temperature of 60 at Concordia, Kansas, 57 at Grand Island, and 62 at Manhattan, Kansas. Haze was reported with a temperature of 63 at Topeka, and 61 at Kansas City. It was partly sunny with a temperature of 56 at Des Moines, and 50 at Sioux Falls." In some areas, a major city would always provide weather conditions; if unavailable, the message the weather conditions were not available would precede the city. (Note: Occasionally, the previous hour's observations as long as 15 minutes into the next hour, which in most cases when this occurs, the product may not be played at all after 15 minutes and will not play until the information is updated.)
[edit] Hazardous Weather Outlook
A hazardous weather outlook is issued daily (usually twice a day at 7AM and 12PM) addressing potentially hazardous weather or hydrologic events that may occur in the next seven days. The outlook will include information about potential severe thunderstorms, heavy rain or flooding, winter weather, extremes of heat or cold, etc. It is intended to provide information to those who need considerable lead time to prepare for the event, along with a call for action for trained weather spotters to be prepared to report their local weather conditions and/or damage reports back to the local NWS office. Other outlooks are issued on an event-driven basis, such as the Flood Potential Outlook and Severe Weather Outlook. Occasionally, the NWS WFO may update the Hazardous Weather Outlook while an event is ongoing or if forecast models denote changes from previous forecasts.
[edit] Sample HWO
Here is a sample from the National Weather Service in Old Hickory/Nashville, TN:
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE NASHVILLE TN 531 AM CDT THU MAR 29 2007 TNZ005>011-022>034-056>066-075-077>080-093>095-301045- STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON- HOUSTON-HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE- SMITH-JACKSON-PUTNAM-OVERTON-FENTRESS-PERRY-HICKMAN-LEWIS- WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DEKALB-WHITE- CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE- GILES- 531 AM CDT THU MAR 29 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF MIDDLE TENNESSEE. .DAY ONE...TODAY AND TONIGHT AREAS OF DENSE FOG WILL REDUCE VISIBILITIES TO ONE QUARTER MILE OR LESS EARLY THIS MORNING. SCATTERED AFTERNOON THUNDERSTORMS WILL REMAIN BELOW SEVERE LEVELS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. SCATTERED THUNDERSTORMS ARE EXPECTED SATURDAY NIGHT AS A COLD FRONT APPROACHES. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME.
[edit] Zone Forecast Product (ZFP)
Text product issued by all WFOs to explicitly state expected weather conditions within each zone in their area of forecast responsibility through day seven.
[edit] Daily Climate Summary
This is a general information product comprised of three separate products:
- Area Climate Summary - generally made available from 5AM to 9AM and mainly available in stations in significant cities in the WFO area of responsibility. In some areas, this product is played on 15 minute intervals. The product includes information on the previous day's recorded minimum and maximum temperatures and the previous and present day's 30-year average minimum and maximum temperatures and record minimum and maximum temperatures, the previous day's recorded precipitation and monthly and annual total precipitation in comparison to the 30-year average monthly and annual precipitation as well as information on heating and/or cooling degree days. In some areas, the sunrise and sunset times for the next two days are displayed in this product, whereas in other areas, the sunrise and sunset times are on a separate product.
- Regional Climate Summary - generally made available from the mid-morning hours to early afternoon featuring actual high and low temperature and precipitation information for regional sections of the WFO displaying information for the 24 hour period starting at 7AM the previous day.
- Afternoon Climate Summary - generally made available from 4PM to 10PM and updated throughout the period. The product includes information on the day's recorded minimum and maximum temperatures and recorded precipitation. Some WFOs station groups also feature in this product: the day's 30-year average minimum and maximum temperatures, record minimum and maximum temperatures and monthly and annual total precipitation in comparison to the 30-year average monthly and annual precipitation.
[edit] Specialty Forecast Products
The following are forecast products that are not available in all NOAA Weather Radio stations or are only played as conditions warrant (Forecast products of any kind [with the exception of Short-Term Forecasts] will be preempted during the occurrence of severe weather):
[edit] Short Term Forecast (NOW)
Sometimes referred to by some stations as a Regional Weather Discussion or the NOW-Cast, this is a localized, event-driven product used to provide the public with detailed weather information during significant and/or fast-changing hydrometeorological conditions during the next six hours. This product on-air will often mention the position of precipitation as detected by NEXRAD radar. This is the one of the few forecast products that is permitted to air during severe weather in addition to routine forecast program cycles.
[edit] Tabular State Forecast Product (SFT)
This is a general seven-day public forecast of hydrometeorological conditions for the entire WFO area of responsibility. This forecast is not part of the regular program cycle, and will only be played on all stations within the WFOs area of resposibility in the event the CRS is down due to technical difficulties or system maintenance.
[edit] Record Information Announcement
This is a product which announces information on tied or newly set records for coldest/warmest maximum and/or minimum temperature and maximum precipitaton. This forecast product is routinely updated when such events occur.
[edit] Surf Zone Forecast (SRF)
This is a text forecast for local beaches issued by coastal WFOs, including coastal hazard information such as that pertaining to rip currents. These products are issued year-round at the Los Angeles/Oxnard, San Diego, and New York City offices, and seasonally at most other coastal offices.
[edit] River Forecast
Daily river forecasts are issued by the 13 River Forecast Centers (RFC) using hydrologic models based on rainfall, soil characteristics, precipitation forecasts, and several other variables. Some RFCs, especially those in mountainous regions, also provide seasonal snow pack and peak flow forecasts.
- River and Small Stream Observations - this product is played in areas in and outside of the 13 River Forecast Centers and is only played following a significant hydrological event featuring information on present flood stage, crest and forecast flood stage.
[edit] Lake Forecast
This is a text product issued by most WFOs in the Great Lakes region to explicitly state expected weather conditions within their marine forecast area of responsibility through day 5. Also addresses expect wave heights.
[edit] Coastal Waters Forecast (CWF)
This is a text product issued by all coastal WFOs to explicitly state expected weather conditions within their marine forecast area of responsibility through day 5. Also addresses expect wave heights.
[edit] Offshore Waters Forecast (OFF)
This is a text product that provides forecast and warning information to mariners who travel on the oceanic waters adjacent to the U.S. coastal waters through day 5. Issued by the Ocean Prediction Center (OPC).
[edit] Emergency Alert Test Procedure
NOAA Weather Radio has a special day and time to test the Public Warning Alarm or Emergency Alert System. The NOAA Weather Radio conducts a weekly warning/watch tone alert test every Wednesday between 10:00 am and Noon. Some NWS Offices conduct a second test in the evening hours, usually at 7:00 pm. If there is a threat of severe weather that day in your NOAA Weather Radio listening area, the test will be postponed until the next available good weather day. The weekly test will replace regular NOAA Weather Radio programming. The SAME Header is sent, followed by the 1050 Hz tone, the text message, and the SAME EOM burst. The text of the test message reads, with variations:
"This is the National Weather Service office in (city). The preceding signal was a test of the warning alarm system of National Weather Service radio station (call sign of station) in (location). During potential or actual dangerous weather situations, specially built receivers are automatically activated by this signal to warn of the impending hazard. Tests of this signal and receivers' performance are usually conducted by this Weather Service office on Wednesdays at (time[s]). When there is a threat of severe weather, or existing severe weather is in the area on Wednesday, the test will be postponed until the next available good-weather day. (Alt. the test will be cancelled, and a short message stating the reason for the cancellation will be broadcast.) Reception of this broadcast, and especially the warning alarm signal, will vary at any given location. The variability, normally more noticeable at greater distances from the transmitter, will occur even though you are using a good quality receiver in perfect working order. To provide the most consistent warning service possible, the warning alarm will be activated only for selected watches and warnings affecting the following counties: (list of counties. N.B. When more than one state is involved, the name of the state comes before the list of counties; for example, on KID-77 in Kansas City, it runs: "in Missouri: Cass, Clay, Jackson, Johnson, Lafayette, Platte, and Ray; and in Kansas: Johnson, Leavenworth, Linn, Miami, Wyandotte, and Douglas.") This concludes the test of the warning alarm system of NOAA Weather Radio (call sign). We now return to normal programming."
[edit] Voices
Prior to 1997, the bulk of NWR programming was via human voice, with a meteorologist recording each message and setting up a looping broadcast cycle. Listeners of NOAA Weather Radio All Hazards enjoyed hearing real people making the broadcasts, but inevitably a more efficient method was needed. As the NWS added more transmitters to provide better radio coverage, WFO staff had difficulty keeping broadcast cycles updated in a timely fashion, especially during large severe weather outbreaks. The NWS then installed a Console Replacement System (CRS) in every forecast office, which introduced a synthesized voice to read text announcements. Because of the large number of geographic terms routinely used in NWR broadcasts, Concatenative Synthesis was not suitable. Instead, an unlimited-vocabulary phonetic synthesizer was employed. This male voice was named "NOAA's Perfect Paul" or simply "Paul", although it quickly acquired several nicknames for its mechanically awkward pronunciation and intonation, including "Igor", "Sven", "Arnold", and Mr. Roboto. Other National Weather Service offices, including Seattle, Oxnard and Las Vegas, used a low-tone voice, known as "Harry".
In 2002, the National Weather Service contracted with Siemens Information and Communication and SpeechWorks to introduce improved, more natural voices [3]. The Voice Improvement Plan (VIP) was implemented, involving a separate computer processor linked into CRS that fed digitized sound files to the broadcast suite. The improvements involved one male voice ("Craig"), and one female voice ("Donna"). Additional upgrades in 2003 produced a greatly improved male voice nicknamed "Tom", which can change intonation based on the urgency of a product; "Donna" was altered as well. Due to the superior quality of the "Tom" voice, most NWS offices use it for the majority of broadcast products. Occasionally, "Donna" can be heard voicing a few products, and the original "Paul" voice usually announces the current local time, some river warnings and in some WFO's, the station identity as required by the FCC (Example: "Station KEC-55, serving the Dallas/Fort Worth listening area"). Full statements will occasionally be heard in the "Paul" voice if the VIP processor gets overloaded with products or a failure occurs.
A few WFOs have had some fun with their synthesized voices by staging contests whereby their listeners can choose a name for the voices. The WFO in Wichita, KS, for example, gave the "Paul" voice the name "Chance Storm"; when the VIP voices came along, they chose the "Donna" voice to broadcast routine products and gave her the name "Misty Dawn". (Incidentally, they have never had such a contest for "Craig" or "Tom", whom they use for urgent products.)
Human voices are still heard on occasion, but sparingly, mainly during station identification, public forecasts, National Ocean Fishery Service Messages, Public Information Statments, Public Service Announcements, weekly tests and severe weather events. The capability exists for a meteorologist to broadcast live on any transmitter if computer problems occur or added emphasis is desired.
Two forecast offices in the continental United States broadcast weather in Spanish: San Diego and El Paso. Both offices use a male Spanish synthesized voice, "Javier".
