Severe Weather Warning Systems

Outdoor Warning System

Oak Grove uses an electronic siren outdoor warning system with voice public address capability.

This system provides additional information as compared to traditional outdoor siren systems. Please remember that sirens are designed to inform persons who are outdoors or in vehicles. Sirens are not designed and cannot be relied on to be heard inside buildings. Please see “NOAA All Hazards Radio” and “Mobile Devices,” below,

General Emergency: Indicated by a three to five minute two tone (hi-lo) siren tone, followed by a voice message describing the type of emergency and action needed. Sample hi-lo siren tone

Severe Thunderstorm Watch: Indicated by a voice message “A Severe Thunderstorm Watch is in effect until (time of expiration).”

A Severe Thunderstorm watch means that conditions are favorable for thunderstorms to develop that have 58 mile per hour or greater winds, 1 inch or larger hail, flooding rains, and dangerous lightning. Severe Thunderstorms may also produce tornadoes with little or no warning. Outdoor activities may need to be cancelled or postponed. Pets should be brought indoors. Loose items such as lawn furniture or trash containers should be secured. Family members should go inside a sturdy structure if threatening conditions approach.

Tornado Watch: Indicated by a voice message “A Tornado Watch is in effect until (time).” A Tornado Watch means that conditions are favorable for thunderstorms to develop that have 58 mile per hour or greater winds, 1 inch or larger hail, flooding rains, dangerous lightning...and tornadoes. A particular term to watch for in Tornado Watch messages is “Particularly Dangerous Situation.” This means that there is an especially high chance of large, long-lived tornados

Severe Thunderstorm Warning: Indicated by a voice message: “A Severe Thunderstorm Watch is in effect until (time).” A Severe Thunderstorm Warning means that a thunderstorm is approaching your location with the winds over 58 miles per hour, hail 1 inch diameter or over, dangerous lighting and/or flooding rains. Remember that severe thunderstorms may produce tornadoes with little or no warning. This message may be accompanied by an interrupted wailing siren (Pulsed Wail) if winds are expected to exceed 70 miles per hour. Sample Pulsed Wail siren.

Tornado Warning. Indicated by a three to five minute interrupted wailing siren (Pulsed Wail) accompanied by a voice message: “A Tornado Warning is in effect until (time). TAKE COVER.” This message indicates that a thunderstorm with a known or suspected tornado and possibly other severe weather conditions is approaching your location. You should immediately take shelter on the lowest floor of a substantial structure, in a small room, and away from windows. If the term “Tornado Emergency” is used in a Tornado Warning message, it means that a large number of tornadoes or large, strong, long-lived tornados are occurring. For more information, view the NOAA website.

Tornado Emergency: A Tornado Emergency is issued when multiple tornadoes are occurring in a relatively small area, and/or the tornadoes are particularly strong and long lived. This message is very rare and indicates the highest level of danger from tornadoes.

NO “All Clear” is sounded for severe weather events. Additional sirens sounding indicate that the hazard is continuing, or that additional warning messages have been issued. For certain non-weather incidents, the Westminster Chime signal may be used with a voice announcement to indicate that the incident has been resolved. Sample Westminster Chime signal.

TESTS: Outdoor warning systems in the Kansas City metro area are generally tested at 11 a.m., on the first Wednesday of each month. These tests may be cancelled or postponed if there is a severe weather threat or in very cold weather. In Oak Grove, the test consists of a voice message announcing the test, one minute of the Pulsed Wail siren, then a second voice message announcing the test. At certain unannounced times, the Emergency Management Department may conduct tests of individual sirens for routine maintenance. These unannounced tests are accompanied by a voice message announcing the test.

NOAA All Hazards Radio

NOAA All Hazards Radio or NOAA Weather Radio (NWR) is a nationwide network of radio stations operated by the National Oceanic and Atmospheric Administration (NOAA). These stations broadcast continuous weather information directly from the nearest National Weather Service office. NWR broadcasts official Weather Service warnings, watches, forecasts, current conditions, and other weather information 24 hours a day, 7 days a week. The radio remains silent, like a pager, until a signal from the National Weather Service turns on the audio to alert you of a message in your county. For Jackson County, the channel to program is 7 (162.55 MHz) located in Independence. For Lafayette County, program channel 2 (162.450 MHz). The radio can also be activated at any time by the press of a button, to give you an up to the minute forecast and weather information. These radios are available at Kansas City area Price Chopper stores for $29.95 as part of a special promotion with Midland Radio Corporation and the Metropolitan Emergency Managers Committee.

Nixle - Smart Phone Text Message System

The City of Oak Grove uses a text and email alerting service called NIXLE. To sign up for this service, visit the website and sign up for the free alerts. Enter your zip code in the box under “What’s Happening Where You Live?” to start. Note: The sites listed above and Nixle do not charge the user for text or email advisories, however, depending on your mobile device service plan, your service provider may charge you for receiving emails or texts.

The City of Oak Grove repeats severe weather watches and warnings and notifications that the Emergency Snow Ordinance is in effect, notifications that the Severe Storm Shelter is open or closed and other emergency and safety messages, on Nixle.

Wireless Emergency Alerts (WEA)

Beginning in June 2012, the Federal Emergency Management Agency and the National Weather Service turned on a new system that will send text alerts to cellular telephones. All new cellular telephones and “smart” phones will be capable of receiving these alerts. There is no cost to the telephone subscriber. Alerts include three types: Presidential Messages, AMBER Alerts, and Imminent Threat Messages.

Presidential Messages are messages of national significance. AMBER Alerts are messages about abducted children. Imminent Threats are warning messages about all other disasters including severe weather, hazardous material spill, evacuation, and other life-threatening emergencies where immediate action is required. In the case of weather related emergencies, only warning messages will be transmitted. Weather watch messages and Severe Thunderstorm Warnings will NOT be transmitted on this system. Since the length of the message is limited to 90 characters, details should be sought from NOAA All-Hazard Radio, local radio or television stations, or the Internet. Telephone subscribers are able to opt out of Imminent Threat or AMBER alert messages. Messages are geographically defined by area, however, there is expected to be slight overlap into neighboring areas.