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TornadoesMore than 85 tornadoes were reported in Virginia in 2004, causing more than $70 million in damage. These tornadoes were rated only F2 or lower on the Fujita scale of wind damage, so it is easy to understand the devastation that could result from a stronger tornado.
Because Virginia tornadoes often emerge from powerful thunderstorms with accompanying rain and lightning, they are often difficult to see until it is too late to take cover. It is essential to listen to local Emergency Alert System stations or to a NOAA weather radio during thunderstorms.
A tornado is a violently rotating column of air extending from a thunderstorm to the ground. Strong tornadoes can reach an awesome intensity, with wind speeds exceeding 200 mph and sometimes even approaching 300 mph. Tornadoes are highly unpredictable, appearing separately or in clusters and varying greatly in length, width, direction of travel and speed.
Tornadoes commonly develop from severe thunderstorms but can also accompany tropical storms and hurricanes as they move onto land.
Though tornadoes can strike at any time, in Virginia they most commonly occur from April to October.
Virtually every region of Virginia has reported at least one tornado over the last 50 years. However, some areas are more susceptible than others. View a Virginia Tornado County map [563kb PDF].
The Enhanced Fujita Scale, or EF Scale, is used to rate the intensity of tornadoes. A tornado’s EF rating is determined by the damage it causes to a man-made structure. It is important to remember that any tornado is potentially dangerous, and that a tornado’s strength can only be determined after it has dissipated. Therefore, it is essential that every tornado be met with every safety precaution.
It is important that businesses know the difference between a tornado watch and a tornado warning, and pay attention to weather announcements during severe thunderstorms.
Read about responding to tornadoes.
