Hurricanes and Severe Weather

Question 1

What are Tropical Cyclones?

Answer 1

Cyclones are large low pressure centers, with numerous thunderstorms, heavy rainfall and winds

Question 2

Where do Tropical Cyclones get their energy from?

Answer 2

They get their energy from the release of latent heat (from evap) during condensation, occurs over warm tropical oceans

Question 3

When do Tropical Cyclones form in North Atlantic and why then?

Answer 3

Late summer, early fall; warmest water temps

Question 4

Where do all Tropical Cyclones originate?

Answer 4

All Tropical cyclones originate in tropics.

Question 5

Where do North Atlantic tropical storms begin?

Answer 5

All Tropical cyclones originate in tropics. North Atlantic tropical storms begin off the coast of Africa

Question 6

What is the growth cycle of North Atlantic Hurricanes?

Answer 6

1. Tropical wave (low pressure off coast of africa)
2. Tropical disturbance
3. Tropical depression (74 mph winds. It has an eye)

Question 7

What is a hurricane?

Answer 7

A hurricane is a tropical storm with wind speeds that have reached a constant of 74 miles per hour or more.

Question 8

What are the different categories of hurricanes according to the Saffir/ Simpson Hurricane Scale?

Answer 8

Category 1 - winds: 74-95mph. 
Category 2 - winds: 96-110mph
Category 3 - winds: 111-130mph
Category 4 - winds: 131-155mph
Category 5 - winds: 156+ mph

Question 9

Strong tropical storms are called Hurricanes, Cyclones, and Typhoons depending on where you are in world. Where in the world are they called these?

Answer 9

North America, Central America - Hurricanes

East Coast of Africa, Madagascar, Australia - Cyclones

Southeast Asia, India, China, Japan, Korea - Typhoons

Question 10

What are the patterns of precipitation in a tropical cyclone?

Answer 10

Look at page 10!

Question 11

What does the eye of a hurricane have?

Answer 11

The eye has sinking air and calm conditions! (higher pressure)

Question 12

What are the strongest winds in a hurricane (other than the eye)?

Answer 12

The top right side of a hurricane has the strongest winds.

Question 13

What are the major risks associated w/ hurricanes?

Answer 13

• High winds
• Heavy rainfall
• Storm surge
• Flooding
• Tornadoes
• Rip tides

Question 14

Which of the major risks associated with hurricane cases the most deaths?

Answer 14

Storm surge is the cause of about 90% of hurricane deaths!

Question 15

What do high winds do to water in hurricanes?

Answer 15

High winds causes the water to pile up higher than the ordinary sea level

Question 16

What is the most deadly natural disaster in the US? How many deaths?

Answer 16

Hurricane of 1900, Galveston, TX. Deaths 6000–8000!

Question 17

What do hurricanes do to coastal landscapes?

Answer 17

Change landscapes dramatically

Question 18

What happened to Harreras Island, NC, September 20, 2003?

Answer 18

Hurricane Isabel slammed into the Outer Banks of North Carolina washing out NC Highway 12 and breaching the island.

Question 19

Why are there no hurricanes at the equator?

Answer 19

..,

Question 20

Why so many cyclones in western Pacific?

Answer 20

…

Question 21

Why are there no tropical cyclones in SW Pacific and SW Atlantic?

Answer 21

….

Question 22

What is the first recorded South Atlantic Hurricane?

Answer 22

Hurricane Catarina (2004)

Question 23

How many thunderstorms occur every day around the globe?

Answer 23

At any given time >2000 thunderstorms are occurring around the globe

Question 24

What are the key ingredients to produce a thunderstorm?

Answer 24

1. Warm, moist air near surface

2. A lifting mechanism, often convection or frontal: given an initial push, air will continue to rise

Question 25

What is an updraft?

Answer 25

...

Question 26

What is a downdraft?

Answer 26

....

Question 27

What causes hail formation?

Answer 27

Strong updraft goes to an area with many supercooled water droplets. This causes the growth of hailstones. A downdraft then causes the hail to precipitate.

Question 28

What is lightning?

Answer 28

Lightning is an atmospheric discharge of electricity, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms.

Question 29

Where does 90% of lightning strikes occur? Why?

Answer 29

90% of all lightning strikes occur over land due to enhanced convection

Question 30

What is thunder? Where is virtually unknown at?

Answer 30

The sudden increase in pressure and temperature from lightning produces rapid expansion of the air surrounding and within a bolt of lightning creates a sonic shock wave. Thunderstorms are virtually unknown at high latitudes >60º

Question 31

Where are thunderstorms most prevalent in the US??

Answer 31

The midwest

Question 32

What are supercells?

Answer 32

Supercell: large storms with strong rotating updrafts, which often burst into stratosphere

Question 33

How do supercells form?

Answer 33

Slide 26

Question 34

Where do most tornadoes originate?

Answer 34

Most tornadoes originate from the base of a thunderhead

Question 35

What is a tornado?

Answer 35

A tornado is a violently rotating column of air in contact with and extending between a cloud (often a thunderstorm cloud) and the surface of the earth.

Question 36

How are tornadoes measured in the Enhanced Fujita Tornado Intensity Scale?

Answer 36

Based on observed damage NOT wind speed (are estimates!)

Question 37

What are the levels of the Enhanced Fujita Scale?

Answer 37

Slide 28

Question 38

What percent of tornadoes fall into the 166-200+ mph range?

Answer 38

Less than 1%

Question 39

What states have the highest geography of Tornadoes?

Answer 39

Midwest (Look at slide 30)

Question 40

What percent of tornadoes are found in North America? Why?

Answer 40

N. Am has 90% of all tornadoes. This is due to uninhibited interaction of air masses! cP and mT available&No E-W mountains to stop clash!

Question 41

Which month has the most tornadoes?

Answer 41

May. June is a close second

Question 42

What are some examples of tornadoes?

Answer 42

Waterspouts, dustdevils, microburst

Question 43

What are Waterspouts?

Answer 43

Small Tornadoes over water: Waterspouts are favored by high temps, high humidity, and still air

Question 44

What are microbursts?

Answer 44

Microburst–Destructive “straight-line”winds up to 160 mph related to thunderstorm downdrafts. Lasts only few minutes. Deadly to small aircraft. Strong downdraft hits ground and spreads out at high speeds (<2 mi, larger are macrobursts)