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...Differences Between a Watch and a Warning...
A severe thunderstorm watch or a tornado watch is issued when atmospheric
conditions are favorable for the development of severe weather.
A severe thunderstorm watch is issued when the primary concern is for large hail
and/or damaging thunderstorm winds. 1 inch (Quarter-sized) or larger hail is
considered severe, as is thunderstorm wind gusts of 58 mph or stronger.
A tornado watch is issued when severe weather is expected, which also includes
the possibility of large and/or multiple tornadoes.
After coordinating with affected National Weather Service forecast offices, the
watch is issued by the storm prediction center in Norman, Oklahoma. The typical
size of a watch area is twenty five thousand square miles and usually takes the
shape of a four-sided polygon. The watch typically lasts for six to eight hours.
When a watch is issued, it is important to be on the alert for threatening weather
and be prepared to move quickly to safety when severe weather develops.
Severe thunderstorm and tornado warnings are issued by local National Weather
Service forecast offices when severe thunderstorms or tornadoes are imminent,
either as indicated by doppler radar or when observed & reported by reliable
sources such as Skywarn spotters. A warning usually covers a portion of one to
several counties (or parishes) and normally lasts for an hour or less. Pay close
attention to the information contained in the warning and take immediate action
to protect yourselves. Warnings include important details such as which locations
are at greatest risk and what measures you should take to protect yourself.
In a watch...watch the sky. In a warning...take action to protect yourself.