1. A tornado is as a rotating, funnel-shaped cloud that extends from a thunderstorm to the ground with whirling winds that can reach 300 miles per hour.
2. Damage paths of tornadoes can be in excess of one mile wide and 50 miles long.
3. Tornadoes can occur when a warm front meets a cold front, forming a thunderstorm, which then can spawn one or more “twisters”.
4. Rotating thunderstorms called mesocyclones (or supercells) are the best predictors of tornado activity. Mesocyclones are well defined thunderstorms on radar that may include hail, severe winds, lightning, or flash floods.
5. Most twisters or cyclones travel from southwest to northeast and can move in the opposite direction for short periods of time. A tornado can even backtrack if it is hit by winds from the eye of the thunderstorm.
6. Funnel clouds usually last less than 10 minutes before dissipating, and many only last several seconds. On rare occasion, cyclones last for over an hour, and many were recorded this way in the early 1900s.
7. A tornado may appear nearly transparent until dust and debris are picked up or a cloud forms within the funnel.
8. Tornadoes can accompany tropical storms and hurricanes once on land.
9. Twisters strike predominantly along Tornado Alley — a flat stretch of land from western Texas to North Dakota. This region is a hotspot for tornadoes because the dry polar air from Canada meets the warm moist tropical air from the Gulf of Mexico.
10. Tornadoes are most likely to occur between 3 and 9 pm, but can occur at any time.
11. In the southern states, peak tornado occurrence is March through May, while peak months in the northernmost states are late June through August.

Practice tornado drills at home, school, and at work. GO [1]

Sources: FEMA [2], Live Science [3]