A tornado is a funnel-shaped whirling cloud which stretches from the base of a thunderstorm to the ground. In larger tornadoes, there may be no funnel shape. It may appear as a large, turbulent cloud near the ground and can be mistaken for a large rain shaft or smoke from a fire. Some can't even be seen because they become wrapped up in rain, hidden from view until it's right on you.
Tornadoes can move erratically, but most travel from southwest to northeast.
Experts once thought tornado winds exceeded 500 mph. In recent years, however, research has shown that winds rarely exceed 250 mph and most tornadoes have winds of less than 112 mph. This means local conditions are favorable for the development of tornadoes. Be alert and ready to take percautions. Tornado Warning A warning means a tornado has been spotted by radar, or by visual contact.