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How Does the National Weather Service Alert You to Potential Severe Weather?


The National Weather Service utilizes a 3-tiered approach to alerting citizens to the potential for severe thunderstorms and/or tornadoes.  The 3 tiers are OUTLOOK, WATCH and WARNING.

Outlook - Be Aware!

Sample SPC Convective Outlook

The National Weather Service's Storm Prediction Center, located in Norman, Oklahoma, is constantly looking for severe weather threats up to a week in advance. The Storm Prediction Center issues “Convective Outlooks” detailing areas where severe weather is possible. Your local National Weather Service office then localizes this information for their forecast area. The NWS in Jackson, KY issues a Hazardous Weather Outlook  every morning, and more often if needed, detailing the severe weather threats over the next week for most of eastern Kentucky. Both the Storm Prediction Center’s Outlooks and NWS Jackson’s daily Hazardous Weather Outlook can be found at

The following graphic can be used to help you understand the categories found on SPC's Convective Outlooks:

Watch - Be Prepared!

Sample SPC Watch

When the threat for an organized severe weather event increases, the Storm Prediction Center will issue a Severe Thunderstorm or Tornado Watch for an area. A Severe Thunderstorm Watch outlines an area where an organized episode of hail 1 inch in diameter or larger and/or damaging thunderstorm winds are expected during a three to eight hour period.  A Tornado Watch includes the large hail and damaging wind threats, as well as the possibility of multiple tornadoes.  Typical watches cover about 25,000 square miles, or about half the size of the state of Kentucky.  If a severe weather watch is issued for your area, prepare for the possibility of severe weather and know what you would do and/or where you would go should a warning be issued.
Watch the video below for more information...


The latest watches issued by the Storm Prediction Center can be found at and will also show up on the map on our website at

Warning - Take Action!

Sample warning map
A Severe Thunderstorm Warning is issued by your local National Weather Service Office when a severe thunderstorm is indicated by the WSR-88D radar or a spotter reports a thunderstorm producing hail one inch or larger in diameter and/or winds equal to or exceeding 58 miles an hour. Lightning frequency is not a criteria for issuing a severe thunderstorm warning.   A Tornado Warning is issued when a tornado is indicated by the WSR-88D radar or a spotter reports a tornado forming or on the ground.    Warnings are usually issued for a duration of one hour or less.  When a Severe Thunderstorm Warning or Tornado Warning is issued, you should take cover immediately

It's important to prepare and have a severe weather action plan in place BEFORE severe weather threatens, and then implement that plan and take action quickly when a warning is issued.  Visit for more information on how to develop your severe weather action plan.