The possibility of a tornado results in a "tornado watch" for a certain area and time.
The actual existence of a tornado results in a tornado warning which is effective until cancelled but may be limited in time.
If a thunderstorm is capable of producing a tornado in the immediate future or if a tornado has been detected then a tornado warning is issued. If general conditions are favorable for tornadoes but there is not necessarily an immediate threat, then a tornado watch is issued.
If a tornado has been detected or spotted then a tornado warning is issued.
If a tornado is spotted a tornado warning is issued.
No, a tornado watch is issued when the general weather conditions can produces tornadoes. If a tornado is spotted a tornado warning is issued.
a tornado warning would be issued if it is in your county and a tornado watch if it is out of your county.
If an announcement indicates a general possibility of tornadoes, but not that there is an imminent danger, then it is called a tornado watch. If there is an imminent threat of a tornado, then a tornado warning is issued.
Tornado warning
The first tornado warning was issued on March 20, 1948 for a storm that produced a tornado in the Oklahoma City area.
If a thunderstorm is capable of producing a tornado in the immediate future or if a tornado has been detected then a tornado warning is issued. If general conditions are favorable for tornadoes but there is not necessarily an immediate threat, then a tornado watch is issued.
If a tornado is spotted or is detected by radar, then a tornado warning will be issued.
Under these circumstances a tornado warning would be issued.
If a possible tornado is seen by spotters or detected by radar a tornado warning is issued. The public is then informed of the warning via special TV and radio announcements, as well as through the internet. Some towns sound sirens that warn of a coming tornado.