During severe weather, the National Weather Service regularly issues watches and warnings for various types of dangerous weather conditions. These alerts are meant to serve as a heads up when impactful weather is on the way. So what's the difference?
Here are some examples of watches and warnings:
A severe thunderstorm watch is issued when conditions are favorable for the development of severe thunderstorms, i.e. a thunderstorm that is capable of producing at least 1" diameter hail and/or wind speeds greater than 58 mph.
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A tornado watch is issued when conditions are favorable for the development of severe thunderstorms capable of producing tornadoes.
A severe thunderstorm warning is issued when a severe thunderstorm has developed, i.e. a thunderstorm that is capable of producing greater than 1" diameter hail and/or wind speeds greater than 58 mph.
A tornado warning is issued when a severe thunderstorm has developed and either has produced a tornado that has been spotted by a ground observer or weather radar indicates intense low-level rotation in conditions that are favorable for tornadic development.
What should you do during a watch or a warning?
During a severe thunderstorm watch, monitor local news or listen to NOAA Weather Radio for emergency broadcasts. Watch for signs that a storm is developing, like darkening skies, lightning or increasing wind.
During a tornado watch, monitor local news or listen to NOAA Weather Radio for emergency broadcasts. Relocate to be near an emergency shelter or a sturdy building to be able to seek immediate shelter within a few minutes.
During a severe thunderstorm warning, take shelter in a substantial building or in a vehicle with closed windows. Evacuate from mobile homes that can be blown over in high winds. If you can hear thunder, you are close enough to be struck by lightning. Remain inside for at least 30 minutes after the last clap of thunder is heard.
During a tornado warning, take immediate shelter in a basement or sturdy building. If you are driving, pull over and park. Put your head down below windows, covering your head with your hands and blanket if available. Stay away from bridges and overpasses.