Deck 11: Thunderstorms

Question 1

Ordinary thunderstorms only last about one hour and begin to dissipate when:

A)lightning neutralizes all the electrical charge in the cloud
B)when all the precipitation particles in the cloud turn to ice
C)when the downdraft spreads throughout the cloud and cuts off the updraft
D)when solar heating at the ground begins to decrease

Answer 1

C

Question 2

Which of the following is the most accurate description of the principle of a lightning rod?

A)the lightning rod acts to discharge the thunderstorm
B)the lightning rod intercepts the lightning and safely carries the lightning current
Around the object it protects
C)lightning rods have been used since the 1700s,but the principle of their
Operation is not known.
D)positive charge induced in the lightning rod repels the negative charge in an
Approaching step leader

Answer 2

B

Question 3

The upper part of a thunderstorm cloud is normally __________ charged,and the middle and lower parts are __________ charged.

A)negatively,negatively
B)negatively,positively
C)positively,positively
D)positively,negatively

Answer 3

D

Question 4

All thunderstorms require:

A)hot,humid air
B)divergence of the air aloft
C)lifting along some barrier such as a mountain or front
D)surface heating
E)rising air

Question 5

The wind shear associated with several major airline crashes is believed to have been caused by:

A)microbursts
B)dry lines
C)the jet stream
D)mesocyclones

Question 6

The downdraft in an ordinary thunderstorm is created mainly by:

A)the melting of snow in the anvil
B)electrical attraction between the cloud and ground
C)the release of latent heat as water in the cloud freezes
D)evaporating raindrops that make the air cold and heavy
E)upper level wind motions

Question 7

In the United States,dryline thunderstorms are most common

A)in the Rocky Mountains
B)in the desert southwest
C)in the Great Plains
D)in California
E)in Florida

Question 8

An ordinary cell thunderstorm is most intense during the __________ stage.

A)mature
B)multicell
C)cumulus
D)dissipating

Question 9

Thunderstorms that move to the right of the winds aloft tend to:

A)form along warm fronts
B)cut off the supply of humid air to thunderstorms to the north of them
C)form in the northern United States and Canada where the Coriolis force is
Greatest
D)form near mountains where upper-level winds develop into waves
E)form over water due to the reduced friction there

Question 10

Severe thunderstorms are capable of producing:

A)large hail
B)tornadoes
C)flash floods
D)all of the above

Question 11

A small thunderstorm cloud with virga falling out of its base and blowing dust at the ground could warn of a severe hazard to an airplane because:

A)this could be the first indication of a tornado
B)it is likely that hail will soon begin to fall
C)this could indicate an intense downdraft or microburst
D)the airplane could be struck by lightning

Question 12

Thunder is caused by:

A)the collision between two thunderstorms with opposite electrical charge
B)the rapid heating of air surrounding a lightning channel
C)the explosion that occurs when + and - charge collide and neutralize each other
D)turbulent wind motions inside the thunderstorm

Question 13

Squall lines generally do not form:

A)behind a cold front
B)when the air aloft develops waves downwind from a cold front
C)along a dry line
D)in the warm sector where warm,dry air meets warm,humid air
E)ahead of an advancing cold front

Question 14

Many flash floods,including those that occurred in Rapid City,South Dakota,and in Colorado's Big Thompson Canyon,are the result of thunderstorms that:

A)contain no lightning
B)form in a dry air mass
C)move slowly
D)have weak or non-existent downdrafts

Question 15

A supercell storm is:

A)a thunderstorm that produces several tornadoes
B)a thunderstorm that produces a category F-5 tornado
C)a thunderstorm with an extremely large downburst
D)an enormous thunderstorm that lasts for several hours

Question 16

Lightning may occur:

A)within a cloud
B)from a cloud to the ground
C)from one cloud to another cloud
D)all of the above

Question 17

You a generally safe inside an automobile during a lighting storm because:

A)the car's radio antenna will act as a lightning rod
B)the rubber tires insulate you from the ground
C)metal cars do not become electrically charged
D)the metal car body will carry the lightning current around the passengers inside

Question 18

A Mesoscale Convective Complex is actually:

A)a rapidly rotating tornado cyclone inside a massive thunderstorm
B)another name for a suction vortex
C)a complex display of lightning from distant thunderstorms
D)a family of tornadoes that do a great deal of damage
E)individual thunderstorms that grow into a large,long-lasting weather system

Question 19

An important principle in the electrification of a cumulonimbus cloud is that:

A)raindrops are always positively charged
B)supercooled water is always negatively charged
C)ice crystals are always negatively charged
D)there is a net transfer of positive ions from a warmer object to a colder object

Question 20

The most likely time for an ordinary call thunderstorm to form is

A)just after sunrise
B)just before sunrise
C)around midnight
D)late afternoon
E)at noon

Question 21

The appearance of a downdraft marks the end of the mature stage of a thunderstorm.

Question 22

Where do thunderstorms form most frequently in the US? Why is this the case? Is this also where most tornadoes occur? Explain.

Question 23

The warm temperatures of a heat burst (a very warm thunderstorm downdraft)are caused by evaporative warming.

Question 24

Severe thunderstorms often occur where the dryline intersects a front or an outflow boundary.

Question 25

In a multicell storm,each of the cells is always in the same stage of development.

Question 26

Thunder will not occur:

A)without lightning
B)in wintertime thunderstorms
C)in thunderstorms over the ocean
D)when a thunderstorm is producing precipitation

Question 27

The low-level jet stream reaches its maximum strength at night.

Question 28

List and describe the sequence of events that occur during a cloud-to-ground lightning discharge.

Question 29

Where does the energy in a mature thunderstorm come from?

Question 30

Jet streaks are thought to have little to do with the development of severe thunderstorms.

Question 31

What is wind shear? Why does wind shear represent a hazard to aviation?

Question 32

In what ways are multicell thunderstorms different from ordinary thunderstorms? What are some of the meteorological or atmospheric conditions that favor the development of multicell thunderstorms?

Question 33

Strong vertical wind shear inhibits the formation of severe thunderstorms.

Question 34

Conditional instability is a favorable condition for thunderstorm formation.

Question 35

The atmospheric conditions that promote the formation of severe thunderstorms tend to prevent many smaller ones from forming.

Question 36

What is a squall line? Where would you expect squall lines to form?

Question 37

List and discuss some of the atmospheric conditions that are needed for a thunderstorm to develop.

Question 38

A supercell storm consists of a single rotating updraft.

Question 39

How does a thunderstorm gust front form? What might you expect to see and feel if a gust front were to approach and pass you on the ground?

Question 40

List and describe the stages of development of an ordinary cell thunderstorm.About how long does a single ordinary thunderstorm cell last?

Question 41

Why is the weather so violent inside a supercell thunderstorm?