WREG.com

Tornado watch vs. warning: What’s the difference?

(WHTM) – With the dog days of summer rapidly approaching, severe weather is not too far behind.

But there is one question that many people ask: What is the difference between a weather watch and a weather warning, and why does it matter?


To put it simply, a weather watch means that the atmosphere is capable of producing whatever weather event the watch is for. For example, if a tornado watch is issued, that means that all of the ingredients to produce a tornado are in place. A watch simply means what it sounds like: Watch the sky and weather radar in case severe weather forms.

A weather warning is much more urgent and serious — very different from a watch. A weather warning means that severe weather is imminent or already occurring.

A tornado warning, for example, means that a tornado is in the process of forming or has already formed. A flood warning, similarly, means flooding is expected or confirmed.

But what makes a certain type of storm — say, a thunderstorm — “severe” enough to warrant a thunderstorm warning?

According to the National Weather Service, a severe thunderstorm warning is issued when winds reach or exceed 58 miles per hour, and/or hail the size of quarters is present within an already formed storm.

Bottom line? A watch concerns possible weather events, whereas a warning concerns more definite weather events. The National Weather Service also urges the public to “take action” when informed of a warning.

More information, as well as the conditions that warrant a weather advisory, can be found at the official website for the National Weather Service.