Tornado warning

A tornado warning (SAME code: TOR) is an alert issued by national weather forecasting agencies to warn the public that severe thunderstorms with tornadoes are imminent or occurring. It can be issued after a tornado or funnel cloud has been spotted by the public, storm chasers, emergency management or law enforcement, or more commonly if there are radar indications of tornado formation.

When this happens, the tornado sirens may sound in that area if any sirens are present, informing people that a tornado has been sighted or is forming nearby (because sirens are not intended to be heard indoors, residents should not completely depend on them. Have more than one way to receive alerts). The issuance of a tornado warning indicates that residents should take immediate safety precautions.

It is a higher level of alert than a tornado watch, but (in the United States) it can be surpassed by an even higher alert known as a tornado emergency.

The first official tornado forecast – and tornado warning – was made by United States Air Force Capt. (later Col.) Robert C. Miller and Major Ernest Fawbush, on March 25, 1948. The first such forecast came after the events that transpired five days earlier on March 20, 1948; Miller – a California native who became stationed at Tinker Air Force Base three weeks earlier – was assigned to work the late shift as a forecaster for the base's Air Weather Service office that evening, analyzing U.S. Weather Bureau surface maps and upper-air charts that failed to note atmospheric instability and moisture content present over Oklahoma that would be suitable for producing thunderstorm activity, erroneously forecasting dry conditions for that night. Thunderstorms soon developed southwest of Oklahoma City, and at 9:30 p.m., forecasters from Will Rogers Airport sent a warning to Tinker that the storm encroaching the city was producing wind gusts of 92 miles per hour (148 km/h) and a "Tornado South on Ground Moving NE!" Base personnel received an alert written by the Staff Sarg. on duty with Miller, minutes before the twister struck Tinker several minutes later around 10:00 p.m., damaging several military aircraft (with total damage estimated at $10 million) that could not be secured in time before it crossed the base grounds.

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