HURRICANES The History, Structure, Development, and Destruction Source:

What is a hurricane? Violent cyclonic storm that develops in the tropical region Wind speeds are > 74 mph Source: Newsroom/NewImages/images.php3?img_id=680

Rotation and Pressure In which direction does a hurricane rotate? COUNTERCLOCKWISE Is the barometric pressure inside the hurricane high or low? LOW

When is Hurricane Season? June 1 st through November 31st

What is the role of the National Weather Service during hurricane season? Provides weather information, such as data from satellites Responsible for issuing watches and warnings to the media and general public

Watch vs. Warning What is the difference between a Hurricane Watch and a Hurricane Warning? Watch – Tropical storm poses a threat to coastal areas with 36 hours Warning - Tropical storm conditions are expected in a coastal area within 24 hours

What conditions must be present for a hurricane to develop? Warm ocean temperatures (>80˚ F) up to 60m deep Little to no wind shear Low pressure system at least 5˚ North or South of Equator Rotation caused by winds Source: gov/oa/reports/fran/fran.html

What is the major source of energy fueling a hurricane? Heat Energy evaporating from the ocean surface Source:

Hurricane Anatomy Source:

Another look at the Structure Source:

Comparison of Terms Tropical Disturbance Group of thunderstorms in the tropics that are present for at least 24 hours Tropical Wave lack of circulation, winds <25 mph and every direction Tropical Depression closed circulation but disorganized, winds at least 25 mph

Tropical Storm Shower and thunderstorm moves over closed circulation, winds greater than 39 mph Hurricane Eye is developed, winds > 74 mph

Compare the Following Source:

By what two factors is hurricane strength measured? Wind Speed Barometric Pressure

What is the Scale Used to Categorize Hurricanes? Saffir-Simpson Scale CategoryMax Wind Speed (mph) Min. Surface Pressure (mb) Storm Surge m (ft) > (3-5) (6-8) (9-12) (13-18) 5> 155< 920> 5.7 (>19) Source:

What causes the damage in a hurricane? Winds Flooding Storm Surge

What is a storm surge? Large wall or dome of water that rushes into the coastline as a result of a hurricane making landfall To the right are the areas affected by high storm surges Souce:

What destroys a hurricane? Strong vertical winds Cold water Movement over land Friction Lack of moisture

What are the five costliest hurricanes in the United States? 1.Katrina (LA/MS/AL/SEFL)2005 $81,000,000,0002.Katrina (LA/MS/AL/SEFL) 2.Andrew (SE FL/SELA) 1992 $34,954,825,0003.Andrew (SE FL/SELA) 3.Wilma (FL) 2005 $20,600,000,0004.Wilma (FL) 4. Ike (TX/LA/MS) 2008 $18,000,000,0005.Ike (TX/LA/MS) 5. Charley (FL) 2004 $14,000,000,000Charley (FL) *Andrew was the only category 5 at landfall. Video: How_Katrina_Grew.asfHow_Katrina_Grew.asf

Explain why the majority of the costliest storms are relatively recent Damage is a result of development There are more developed areas and possessions than in the past Source:

What are the five deadliest hurricanes in the United States? 1. Galveston – Lake Okeechobee Fl. – Katrina Florida Keys – New England – 1938

Explain why the deadliest storms were longer ago. Lack of instrumentation to predict and track storms People were not warned of the incoming danger Source: Results of the Galveston Hurricane

How are hurricanes named? Source: There are actually six lists of names in use for storms in the Atlantic. These lists rotate, one each year. The names get recycled each time the list comes up, with one exception: storms so devastating that reusing the name is inappropriate. In this case, the name is taken off the list and another name is used to replace it; there will not be another Hurricane Andrew, because Andrew has been replace by Alex on the list.

What are the 2011 hurricanes? Source: ArleneBret Cindy Don EmilyFranklin Gert Harvey IreneJose Katia Lee MariaNate Ophelia Philippe RinaSeanTammy Vince Whitney

How has a hurricane affected you personally? Damage to your house from wind? Damage from flooding? Destroyed vacation house? Damage to family members’ homes?

Final Water Level Flooding of Tar River as result of Hurricanes Dennis and Floyd Dockside Tar River Estates

Damage to Greenville Extensive Flooding Extended Power outages Flood Related Deaths Property Damage US 264 Bridge Source: /hazard/event/floyd/ncflood/ mediums/img022.jpg

Damage from Floyd Source:

Protection Listen to warnings Take all warnings seriously Follow evacuations Prepare Food and Water for extensive power outages

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