Storms Chapter 6.4

Storm A violent disturbance in the atmosphere. Involves… *sudden change in air pressure *rapid air movements

How do the different types of storms form? Winter Storms – dry, cold air masses move over lakes picking up water vapor and heat resulting in heavy snows Thunderstorms – form in large cumulonimbus clouds Hurricanes – begin over warm ocean water as a low-pressure area Tornadoes – develop in thick cumulonimbus clouds

Winter storms As cold, dry air moves across the warmer water, it becomes more humid as water vapor from the lake surface evaporates. When the air reaches land and cools, snow falls. Chicago, because it is west of Lake Michigan

Thunderstorm A small storm with heavy precipitation and frequent thunder and lightning. Form in… large cumulonimbus clouds known as thunderheads

How thunderstorms form pg. 210 Cold air moves downward Warm, humid air rises.

Lightning An energy discharge caused when charges jump between parts of a cloud, between clouds, or between the clouds and the ground.

Hurricane A tropical cyclone with winds of 119 km/h or higher. Hurricanes begin over warm ocean water as a low-pressure area, or tropical disturbance.

Hurricane pg. 212 weak strong strong

Hurricane strength is ranked on the Saffir-Simpson Hurricane Scale.

Storm surge A “dome” of water that sweeps across the coast where the hurricane lands. This can… *wash away beaches *destroy coastal buildings *erode coastlines

Hurricane Video clip

Tornado A rapidly whirling, funnel-shaped cloud that reaches down to touch Earth’s surface. Commonly develop in thick cumulonimbus clouds. If over water, called a waterspout.

Pg. 214 1. Is the risk of tornadoes in Florida relatively low or relatively high? 2. Which state might have more tornadoes than Florida? Relatively high

Tornado Hits

I get it! Now I know that the main kinds of storms are… pg. 215 Winter storms 2. Thunderstorms 3. Hurricanes 4. Tornadoes