Hurricane Ike

Hurricane Gustav

How does weather affect society?

What is a Hurricane?One of three names used to

describe rotating tropical storms with a wind of at least 74 mph.

Hurricane – Atlantic OceanCyclone – Indian OceanTyphoon – Western Pacific

Tropical Depressions – Wind speeds of 38 mph

Tropical Storms – Winds of over 39 mph

Hurricanes – Winds of at least 74 mph

How Does a Hurricane Form?• Warm moist air moves over the ocean

• The Ocean water MUST be over 80°F

• Water Vapor rises into the atmosphere (less dense)

• Creates a LOW pressure system

As water vapor cools it condenses into liquid droplets

Condensation releases heat energy, feeding the hurricane

Warmed air continues to rise, cooler air replaces the warm rising air creating more wind

Coriolis EffectIn the Northern

Hemisphere hurricanes rotate counter clockwise

In the Southern Hemisphere hurricane rotate clockwise

Anatomy of a HurricaneEye – Low pressure center of the hurricane

Eye Wall – Surrounds the eye, most violent part of storm

Rain bands – Bands of rain showers with gusty winds, outermost layer

Hurricane Structure

Hurricane CategoriesSaffir – Simpson Scale

Category 1: 74-95 mphCategory 2: 96-110 mphCategory 3: 111-130 mphCategory 4: 131-155 mphCategory 5: 155+ mph

Hurricane DamageRainFloodingHigh Sustained

WindsStorm SurgeTornadoes

How do Hurricanes end?Hurricanes lose energy when they go over

landHurricanes can lose energy when they move

over colder waterThere is no moisture or heat to feed the

hurricane

Hurricane SeasonJune 1 to

November 30 in the Atlantic, Caribbean, Gulf of Mexico, and Central Pacific

May 15 to November 30 in the Eastern Pacific

Famous Hurricanes

Galveston, TexasHurricane AndrewHurricane CamilleHurricane FloydHurricane Hugo

Hurricane Katrina