1. 20.3 Severe Storms Vocabulary

2. Thunderstorm Thunderstorm is produced by a cumulonimbus cloud and always accompanied by lightening and thunder.

3. Tornado A tornado is a small, very intense cyclone storm with exceedingly high winds, most often produced along cold fronts in conjunction with severe thunderstorms.

4. Hurricane Hurricane is a tropical cyclone storm having winds in excess of 119 kilometers per hour.

5. Eye Wall Eye wall is the doughnut-shaped area of intense cumulonimbus development and very strong winds that surrounds the eye of a hurricane.

6. Eye The eye is a zone of scattering clouds and calm averaging about 20 kilometers in diameter at the center of a hurricane.

7. Storm Surge Storm surge is the abnormal rise of the sea along a shore as a result of strong winds.

8. Key Concepts

9. A thunder storm is a storm that generates lightening and thunder Thunderstorms frequently produce gusty winds, heavy rain, and hail.

10. Thunder storms form when warm, humid air rises in an unstable environment.

11. Tornadoes are violent windstorms that take the form of a rotating column of air called a vortex. The vortex extends downward from a cumulonimbus cloud.

12. Most tornadoes form in association with severe thunderstorms.

13. Whirling tropical cyclones that produce winds of at least 119 kilometers per hour are known in the United States as hurricanes.

14. Hurricanes develop most often in the late summer when water temperatures are warm enough to provide the necessary heat and moisture to the air.