When severe weather is approaching, watches and warnings are issued to inform the public of impending threats. There is a distinct difference between a watch and a warning, and knowing the difference can save your life.
“Watches, like severe thunderstorm watches and tornado watches, which are two of the most common types, are issued when weather conditions are conducive for the event to occur,” AccuWeather.com Senior Meteorologist Mike Pigott said.
The Storm Prediction Center (SPC) defines a “severe thunderstorm watch” by outlining an “area where an organized episode of hail one inch in diameter or larger and/or damaging thunderstorm winds are expected during a three- to eight-hour period.”
A “tornado watch,” for example, includes the “large hail and damaging wind threats, as well as the possibility of multiple tornadoes,” according to the SPC. Typically, most watches cover roughly 25,000 square miles.
Watches are issued by the SPC. Warnings are issued by local National Weather Service (NWS)stations.
“Warnings are different. A warning is issued when the weather event is happening now,” Pigott said. “In terms of flooding, for instance, a flood warning means a river has spilled over or flash flooding is occurring.”