Chapter 6Lesson 3

WeatherBy: Tyler C. and Saagar D.

What Causes Severe Weather? Sometimes winds and the water cycle

can lead to dangerous weather. Severe weather includes

thunderstorms, tornadoes, hurricanes, and monsoons.

Thunderstorms Different areas of thunderstorms cloud have

either positive or negative electrical charges.

Thunderstorms have three stages: - First stage: All air currents move upwards - Second Stage: Air currents are mixed - Final stage: All air currents move downwards

Tornadoes Tornadoes are a rotating column of air that extends

from a thunderstorm to the ground. How tornadoes form: - Before thunderstorms form, winds change direction and increases in speed. Winds begin to spin. - As the thunderstorms form, air within it rises. The spinning air begins to tilt upwards. - The area of spinning grows wider.

A tornado

Hurricanes Hurricanes are a dangerous cyclonic storm made up of swirling

bands of thunderstorms with wind speeds of at least 119 kilometers per hour that forms over warm ocean water.

How Hurricanes form: - Thunderstorms grow out of a tropical depression. - Air pressure at the ocean’s surface drops. Surface winds blow faster and begin to swirl. A tropical storm develops. -Thunderstorms begin to move in spiral bands. Air pressure drops lower, and surface winds blow faster.

A hurricane in Hawaii

Monsoons Monsoons forms when air over the ocean is

cooler then air over land. Then, the moist air over the ocean moves towards land.

Tempered describes air that is warmed in winter and cooler in summer because it is near a large body of water.

A monsoon is a wind that changes direction with the season.

A monsoon in India