TODAY’S VOCABULARY

• HURRICANE: Tropical storm with wind speeds in excess of 74 mph.

METEOROLOGY UNIT

Violent Weather - Hurricanes

VIOLENT WEATHER…..

• http://video.nationalgeographic.com/video/101-videos/hurricanes-101

• http://video.nationalgeographic.com/video/101-videos/tornadoes-101

• http://video.nationalgeographic.com/video/101-videos/lightning

PARTS OF A HURRICANE

• Start off as a tropical storm off coast of Africa

• Named when winds >39 mph

• Hurricane when winds >74 mph

PARTS OF A TORNADO

• Funnel Cloud• Center part

sometimes called the ‘vortex’

• Drops out of supercell thunderstorms

CLASSIFTYING HURRICANESSaffir Simpson Scale

•Category 1: Winds of 64-82 knots (74-95 mph)Very dangerous winds will produce some damage•Category 2: Winds of 83-95 knots (96-110 mph)Extremely dangerous winds will cause extensive damage•Category 3: Winds of 96-113 knots (111-129 mph)Devastating damage will occur•Category 4: Winds of 114 to 135 knots (130-156 mph)Catastrophic damage will occur•Category 5: Winds above 135 knots (157 mph)Catastrophic damage will occur

CLASSIFYING TORNADOESFUJITA SCALE•F-0 40-72 mph, Light damage, chimney damage, tree branches broken•F-1 73-112 mph, Moderate damage, mobile homes pushed off foundation or flipped over•F-2 113-157 mph, Considerable damage, mobile homes demolished, trees uprooted•F-3 158-205 mph, Severe damage, roofs and walls torn down, trains overturned, cars thrown around•F-4 207-260 mph, Devastating damage, well-constructed walls leveled•F-5 261-318 mph, Violent damage, homes lifted off foundation and carried considerable distances, autos thrown as far as 100 meters.

TORNADOES

• Small• Forms over land• Spring• Lasts a few minutes• Highest wind speeds – 300 mph• ? Dies out• F0 – F5Damage from wind, hail

HURRICANES• Large• Forms over tropical waters• Late summer/fall• Can last days• Highest wind speeds --- 160 mph • Dies out over land / cold water• Category 1-5Damage from wind, water (storm

surge) , can spawn tornadoes

More facts…..

TORNADO• Forms from supercell

thunderstorms• The greater the difference

in air pressure between high and low and pressure air masses, the more likely a tornado will result

• Center is low pressure• Circulate counter clockwise

HURRICANE• Ocean warmer than 26 oC• Low pressure in center

great enough, storm starts to spin into the center

• Circulate counter clockwise• Dissipate over land and/or

cold water

TODAY’S ACTIVITY

• TRACKING HURRICANES

TICKET OUT THE DOOR

• Hurricanes that hit the Southeast United States start …………………