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, funnel cloud and rotation in the clouds has been spotted by the public, storm chasers, emergency management or law enforcement.
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 may be forming nearby (because sirens are generally not heard indoors, residents should not completely depend on them). 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 or Particularly Dangerous Situation warning.

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