What Happens When Good What Happens When Good Weather Goes Bad?Weather Goes Bad?

StormsStorms

A Storm is a violent disturbance in the A Storm is a violent disturbance in the atmosphereatmosphere

Cause sudden changes in air pressureCause sudden changes in air pressure Cause rapid air movementsCause rapid air movements

ThunderstormsThunderstorms

FormationFormation Form within large cumulonimbus cloudsForm within large cumulonimbus clouds Usually form when warm air is forced upward Usually form when warm air is forced upward

at a cold frontat a cold front Produce strong upward and downward winds Produce strong upward and downward winds

inside cloudsinside clouds

ThunderstormsThunderstorms

LightningLightning Positive and negative electrical charges build Positive and negative electrical charges build

up in a stormup in a storm Lightning is a sudden energy discharge as the Lightning is a sudden energy discharge as the

charges jump between parts of a cloudcharges jump between parts of a cloud ThunderThunder

Lightning heats up air to almost 30,000 Lightning heats up air to almost 30,000 degrees Cdegrees C

The air expands explosively – thunder is the The air expands explosively – thunder is the sound of the explosionsound of the explosion

TornadoesTornadoes

Tornado – a rapidly whirling funnel shaped Tornado – a rapidly whirling funnel shaped cloud that reaches down from a storm cloud that reaches down from a storm cloud to touch the earth’s surfacecloud to touch the earth’s surface

Waterspout – a tornado that touches down Waterspout – a tornado that touches down on the wateron the water

FormationFormation Develop in low, heavy cumulonimbus cloudsDevelop in low, heavy cumulonimbus clouds Most likely to occur in spring and early Most likely to occur in spring and early

summersummer

HurricanesHurricanes

Hurricane – a tropical storm with winds of 74 Hurricane – a tropical storm with winds of 74 mph or higher – measured on the Saffir-Simpson mph or higher – measured on the Saffir-Simpson ScaleScale Category 1 – winds 74-95 mph – Gaston of 2004Category 1 – winds 74-95 mph – Gaston of 2004 Category 2 – winds 96-110 mph – Frances 0f 2004Category 2 – winds 96-110 mph – Frances 0f 2004 Category 3 – winds 111-130 mph – Jeanne ’04, Category 3 – winds 111-130 mph – Jeanne ’04,

Wilma ’05Wilma ’05 Category 4 – winds 131-155 mph – Charley ’04 Category 4 – winds 131-155 mph – Charley ’04 Category 5 – winds 156 + mph – Andrew 1992Category 5 – winds 156 + mph – Andrew 1992

Are also called Typhoons and Tropical CyclonesAre also called Typhoons and Tropical Cyclones

HurricanesHurricanes

FormationFormation Hurricanes typically form over warm water a a Hurricanes typically form over warm water a a

low-pressure area or tropical disturbancelow-pressure area or tropical disturbance Hurricanes get their energy from the warm, Hurricanes get their energy from the warm,

humid air at the ocean’s surfacehumid air at the ocean’s surface The EyeThe Eye

Calm area at the center of the storm. The Calm area at the center of the storm. The better developed the eye, the stronger the better developed the eye, the stronger the stormstorm

After the eye passes over, the wind blows After the eye passes over, the wind blows from the opposite directionfrom the opposite direction

Hurricane PreparationsHurricane Preparations

In areas where hurricanes hit frequently, In areas where hurricanes hit frequently, like Florida, hurricane shutters are like Florida, hurricane shutters are required by building coderequired by building code

Hurricane shutters should be put up when Hurricane shutters should be put up when a hurricane watch is issueda hurricane watch is issued

Hurricane supplies should be stocked up Hurricane supplies should be stocked up before the season – bottled water, canned before the season – bottled water, canned foods, medications, flashlights, batteries, foods, medications, flashlights, batteries, weather radio, etc.weather radio, etc.

Historic Catastrophic StormsHistoric Catastrophic Storms

Only 3 Category 5 storms have ever hit Only 3 Category 5 storms have ever hit the USthe US

Labor Day Hurricane of 1935 – Florida Labor Day Hurricane of 1935 – Florida KeysKeys

Hurricane Camille of 1969 – Pass Hurricane Camille of 1969 – Pass Christian in Mississippi Gulf CoastChristian in Mississippi Gulf Coast

Hurricane Andrew of 1992 – Florida City Hurricane Andrew of 1992 – Florida City and Miami-Dadeand Miami-Dade

Damage from AndrewDamage from Andrew

Recent Catastrophic StormsRecent Catastrophic Storms

KatrinaKatrina Category 5 storm at its strongestCategory 5 storm at its strongest Category 3 storm when it made landfallCategory 3 storm when it made landfall

20

25

30

35

40

-95 -90 -85 -80 -75 -70

Hurricane Katrina23-31 August

Hurricane

Tropical Storm

Tropical Dep.

Extratropical

Subtr. Storm

Subtr. Dep.

00 UTC Pos/Date

12 UTC Position

Low / Wave

PPP Min. press (mb)

25

24

31

30

29

2827

26

902 mb

920 mb

984 mb

928 mb

Hurricane WilmaHurricane Wilma

Strongest storm on record for Atlantic Strongest storm on record for Atlantic tropical cyclone with a minimum pressure tropical cyclone with a minimum pressure of 882 mbof 882 mb

Category 5 storm at that timeCategory 5 storm at that time Category 3 storm when it made landfall in Category 3 storm when it made landfall in

FloridaFlorida Landfall made on the Gulf Coast of Landfall made on the Gulf Coast of

Florida, and predicted to lose strength as it Florida, and predicted to lose strength as it went across Florida – it didn’t!went across Florida – it didn’t!

15

20

25

30

35

40

45

-85 -80 -75 -70 -65 -60 -55 -50 -45

Hurricane Wilma15-25 October 2005

Hurricane

Tropical Storm

Tropical Dep.

Extratropical

Subtr. Storm

Subtr. Dep.

00 UTC Pos/Date

12 UTC Position

Low / Wave

PPP Min. press (mb)

25

24

23

22

21

20

1918

26

1617

882 mb