Deck 10: Thunderstorms and Tornadoes

Question 1

Where in the thunderstorm would you be most likely to find mammatus clouds?

A) Letter E
B) Letter F
C) Letter C
D) Letter D

Answer 1

Letter E

Question 2

Multiple- vortex tornadoes help explain:

A) why tornadoes are so short lived.
B) why some tornadoes never touch the ground.
C) what EF rank a tornado should have.
D) why one building is destroyed and the one next to it is untouched.

Answer 2

D

Question 3

A squall line is most likely to develop where?

A) along a cold front
B) in the middle of a cP air mass
C) along a warm front
D) along a dryline in the warm sector of a mid- latitude cyclone

Answer 3

along a dryline in the warm sector of a mid- latitude cyclone

Question 4

The term cyclone is BEST defined as:

A) a violent tornado.
B) a hurricane.
C) any circulation around a low- pressure center.
D) a storm that develops over an ocean.

Question 5

What is the deadliest tornado on record in the United States?

A) the Moore, OK tornado of 1999
B) the Fargo, ND tornado of 1957
C) the Natchez tornado of 1840
D) the Tri- State tornado of 1925

Question 6

Which type of lightning is LEAST likely?

A) cloud- to- Earth
B) within the same cloud
C) cloud- to- cloud

Question 7

How is global climate change expected to impact thunderstorm activity in the United States over the next century?

A) Climate change will have no definable impact on thunderstorm days.
B) Thunderstorm days are expected to decrease in the Southeastern United States.
C) More thunderstorms will occur in every state of the nation.
D) The environment necessary for severe thunderstorms will occur on more days for most locations east of the Rockies.

Question 8

Because of the tremendous pressure gradient associated with a strong tornado, maximum winds approach________ miles per hour.

A) 300
B) 1000
C) 100
D) 600

Question 9

Why is very humid air near the surface a necessary ingredient for severe thunderstorms?

A) High humidity strengthens the cold front.
B) High humidity makes the rising air cool more rapidly.
C) Lapse rates are larger in humid air.
D) High humidity makes the air more dense.
E) More latent heat is then available as energy for the storm.

Question 10

Updrafts dominate the cumulonimbus cloud during the in ____the life cycle of an air mass thunderstorm.

A) dissipating stage
B) mature stage
C) cumulus stage

Question 11

Which of the following statements is NOT true of tornadoes?

A) associated with cumulonimbus clouds
B) occur most frequently in the spring of the year
C) generally move from the southwest toward the northeast
D) usually occur along the warm front of a midlatitude cyclone

Question 12

About what percent of thunderstorms in the United States become severe?

A) 10%
B) 20%
C) 50%
D) 25%

Question 13

Downdrafts totally dominate the_____ of an air mass thunderstorm.

A) cumulus stage
B) dissipating stage
C) mature stage

Question 14

Why do most tornadoes tend to travel in the same general direction?

A) They have an intense pressure gradient force.
B) They generally occur in a zone of southwest winds.
C) Tornadoes often occur to the east of the center of a midlatitude cyclone.
D) Because of their clockwise rotation.

Question 15

The leading edge of a gust front is frequently associated with:

A) hail.
B) heavy precipitation.
C) tornadoes.
D) the development of a new cumulonimbus cloud.

Question 16

Why are air mass thunderstorms most likely to occur in the midafternoon?

A) Water- vapor contents are too low at night.
B) Upper- level winds are too fast at night and in morning.
C) Atmosphere is most unstable at that time.
D) It takes all day for them to mature.

Question 17

The total discharge of lightning is made up of several rapid strokes and is known as the:

A) leader.
B) flash.
C) bolt.
D) strike.

Question 18

Doppler radars:

A) have much greater range than conventional radars.
B) show the motion of precipitation particles.
C) detect lightning strokes.
D) detect condensation nuclei.
E) show the motion of air in clear areas.

Question 19

About how many thunderstorms take place on Earth every day?

A) 1300
B) 45,000
C) 300
D) 5000

Question 20

Which association is incorrect?

A) anvil - front of the thunderstorm
B) downdraft - precipitation
C) mesocyclone - region of tornado formation
D) tornado watch - a tornado has been sighted on the ground

Question 21

What is entrainment?

A) a line of thunderstorms, one feeding into the next
B) warm, moist air fed into a thunderstorm by the updraft
C) rotation from the parent cloud transferring into a tornado
D) the process of cool, dry air being pulled into a thunderstorm by the downdraft

Question 22

What does the term mesocyclone refer to in reference to a tornado?

A) a very large tornado
B) a false- alarm tornado warning
C) a high- altitude tornado
D) the rotation of the updraft in the parent thunderstorm

Question 23

The diameter of a typical tornado funnel cloud would be:

A) 150 - 600 meters.
B) 1000 - 2500 meters.
C) 3000 meters.
D) 50 - 100 meters.

Question 24

Hurricanes and thunderstorms can sometimes cause rapidly rising local floods that are short- lived but high volume. These are called:

A) 100- year floods.
B) flash floods.
C) surge floods.
D) rapid floods.

Question 25

The circulation in the immediate vicinity of a thunderstorm is:

A) variable and gusty.
B) anticyclonic.
C) calm.
D) cyclonic.

Question 26

Why do most tornadoes in the central U.S. occur during the spring months?

A) Divergence of air aloft is greatest.
B) Surface air is most humid.
C) Upper- air temperatures are warmest.
D) Solar energy is a maximum.
E) Air- mass contrasts are greatest.

Question 27

Mesoscale convective complexes:

A) occur along dry lines.
B) begin as air mass thunderstorms that form in the afternoon.
C) do not provide any benefit to agriculture.
D) tend to die out as soon as the sun goes down.

Question 28

An overshooting top means that:

A) lightning strikes will be especially intense.
B) the thunderstorm has very strong updrafts causing the cloud to grow into the stratosphere.
C) the thunderstorm is dissipating.
D) a thunderstorm will DEFINITELY produce a tornado.

Question 29

Which of the following demonstrates the correct order of the phases involved in a lightning stroke?

A) dart leader, charge separation, flow of negative charge into ground, step leaders, return stroke
B) charge separation, dart leader, step leaders, flow of negative charge into ground, return stroke
C) step leaders, return stroke, separation of charges, flow of negative charge into ground, dart leader
D) charge separation, step leaders, return stroke, flow of negative charge into ground, dart leader

Question 30

The terms leader, flash, and stroke are used when describing:

A) a tornado.
B) lightning.
C) the passage of a hurricane.
D) squall line formation.
E) the stages of a thunderstorm.

Question 31

The feature identified by Letter F is most likely:

A) in the stratosphere.
B) the sign of an intense downdraft.
C) in the mesosphere.
D) the beginning of a new thunderstorm cell.

Question 32

Conventional radar measures:

A) raindrop and snowflake motion.
B) cloud droplet numbers.
C) raindrop size.
D) raindrop motion.
E) rainfall intensity.

Question 33

____________are relatively narrow, elongated bands of thunderstorms that develop in the warm sector of a middle- latitude cyclone, usually in advance of a cold front.

A) Roll clouds
B) Mesocyclones
C) Supercells
D) Squall lines

Question 34

If you see lightning and then hear the associated thunder 10 seconds later, the lightning flash was about ______mile(s) away.

A) two
B) four
C) three
D) one
E) five

Question 35

Extreme evaporative cooling can sometimes produce explosions of straight- line winds called:

A) gust fronts.
B) tornadoes.
C) downbursts.
D) air bombs.

Question 36

A roll cloud forms in association with which other common thunderstorm feature?

A) the updraft
B) the precipitation
C) the anvil
D) the gust front

Question 37

Of the following states, which is struck by the largest number of tornadoes?

A) North Carolina
B) Oklahoma
C) Ohio
D) North Dakota
E) New Mexico

Question 38

Which of the following should have the steepest pressure gradient?

A) tornado
B) hurricane
C) middle- latitude cyclone
D) typhoon

Question 39

The feature identified by Letter D is:

A) a cold front.
B) the storm's anvil.
C) experiencing very calm conditions.
D) the gust front.

Question 40

What causes the dissipating stage of a thunderstorm?

A) spreading downdraft cuts off air inflow
B) converging winds aloft
C) loss of radiant energy from cloud top
D) converging surface winds
E) release of latent heat within the cloud

Question 41

Downdrafts and updrafts found side by side occur during the___________ in the life cycle of an air mass thunderstorm.

A) mature stage
B) dissipating stage
C) cumulus stage

Question 42

A tornado is a small, very intense example of the:

A) jet stream.
B) Coriolis effect.
C) cyclone.
D) anticyclone.
E) geostrophic wind.

Question 43

Why is strong heating of the ground by the Sun associated with thunderstorms?

A) increases the pressure gradient
B) leads to greater instability
C) reduces the relative humidity
D) increases the wind speed
E) reduces the dew point

Question 44

An air mass thunderstorm is most intense during the ___________stage.

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

Question 45

Thunderstorms and large cumulonimbus clouds are characteristic of:

A) all polar air masses.
B) stable air.
C) unstable air.
D) isothermal lapse rates.

Question 46

Drylines are capable of producing thunderstorms because:

A) there is an abrupt change in temperature across the dryline.
B) the dry air mass forces the moist air mass to rise.
C) the moist air mass lifts the dry air mass.
D) the dry air mass is unstable and rising.

Question 47

Tornadoes are most frequent during the:

A) January- March period.
B) month of September.
C) April- June period.
D) July- August period.
E) October- December period.

Question 48

More than half of all the flash- flood deaths occurring in the United States:

A) occur in the winter when people are not expecting severe weather and are less aware.
B) happen in the early morning hours.
C) are a result of poor decisions made by drivers who encounter flooded roadways.
D) occur during mesoscale convective complexes.

Question 49

Where would you expect to find precipitation occurring in this thunderstorm?

A) Letter A
B) Letter B
C) Letter E
D) Letter D

Question 50

In which of the following places are thunderstorms most common?

A) northern Wisconsin
B) central Nevada
C) central Florida
D) west of Hudson Bay (Canada)
E) The occurrence of thunderstorms at all of these places should be about the same.

Question 51

Which of the following U.S. states experiences the most thunderstorms each year?

A) Oklahoma
B) Texas
C) Colorado
D) Florida

Question 52

A tornado that does devastating damage and has estimated wind speeds of 300 km/hr (186 mph) would be ranked as an:

A) EF- 3.
B) EF- 5.
C) EF- 2.
D) EF- 4.

Question 53

A microburst is:

A) a brief, intense explosion of lightning.
B) rarely damaging.
C) associated only with tornadic thunderstorm cells.
D) another name for a downburst.

Question 54

The gust front occurs:

A) on the lee shore of the Great Lakes.
B) at the leading edge of a thunderstorm downdraft.
C) during the development of thunderstorm clouds.
D) near the anvil part of a thunderstorm cloud.

Question 55

Thunderstorms can be associated with these weather activities:

A) cyclones.
B) tornadoes.
C) hurricanes.
D) cyclones, hurricanes, and tornadoes.

Question 56

Thunderstorms form when________-- , humid air rises in a(n)__________ environment.

A) cold; stable
B) warm; unstable
C) warm; stable
D) cold; unstable

Question 57

At what time of day is an air- mass thunderstorm more likely to develop?

A) midnight
B) midmorning
C) pre- dawn
D) midafternoon

Question 58

An air mass thunderstorm rarely lives long enough to create very severe weather because:

A) the atmosphere is generally fairly stable when these storms develop.
B) there is rarely enough moisture available to keep the storm alive for longer than 30 minutes.
C) wind shear causes the storm's updraft to become tilted.
D) the downdrafts quickly become strong enough to stop the updraft and influx of moisture to the storm.

Question 59

The Enhanced - Fujita Intensity Scale (EF- scale) is applied to:

A) typhoons.
B) tornadoes.
C) lightning.
D) thunderstorms.

Question 60

Generally there are three stages involved in the development of air mass thunderstorms. They are:

A) cumulus stage, adolescent stage, and dissipating stage.
B) cumulus stage, mature stage, and dissipating stage.
C) cumulus stage, mature stage, and deconstructing stage.
D) cumulus stage, dissipating stage, and deconstructing stage.

Question 61

What are the three stages in the development of a thunderstorm? Draw a diagram of each, labeling updrafts and downdrafts as appropriate.

Question 62

It is impossible to warn people of every lightning flash because:

A) it kills few people compared to the other types of severe weather, so it isn't studied as much.
B) scientists don't understand exactly how it forms.
C) it strikes so frequently and in so many places.
D) people are only struck by lightning a few times each decade, so most don't listen to warnings.

Question 63

Thunderstorm tops most likely occur:

A) in the middle stratosphere.
B) in the mesosphere.
C) near the tropopause.
D) in the lower troposphere.

Question 64

How are both positively and negatively charged particles able to form in the same thunderstorm cloud?

Question 65

A dryline generally forms between which two air masses?

A) cT and mT
B) mP and mT
C) cP and mT
D) cP and cT

Question 66

What makes the narrow, rotating air column or vortex of a tornado visible?

Question 67

At any given time, about how many thunderstorms are in progress on Earth?

A) 45
B) 45,00
C) 500
D) 2,000

Question 68

Tornadoes most often move toward what direction?

A) west
B) southwest
C) northwest
D) northeast
E) southeast

Question 69

Which of the numbers listed below best represents the percentage of thunderstorms that produce tornadoes?

A) fewer than 1 percent
B) slightly more than 50 percent
C) about 10 percent
D) nearly 25 percent

Question 70

The feature identified by Letter F is:

A) a mammatus cloud.
B) a feature marking the downdraft.
C) a roll cloud.
D) an overshooting top.

Question 71

Thunderstorms occur year- round in the:

A) tropics.
B) middle latitudes.
C) subarctic regions.
D) subtropics.
E) polar regions.

Question 72

In the development of a thunderstorm, sharp and cool gusts beginning at the surface are characteristic in the___________ .

A) dissipating stage
B) cumulus stage
C) mature stage

Question 73

Which feature of the thunderstorm is created by the gust front?

A) Letter A
B) Letter F
C) Letter C
D) Letter D

Question 74

Why is so- called "heat lightning" not associated with thunder?

Question 75

Some of the most dangerous weather is produced by a type of thunderstorm called a(n):

A) gust front.
B) supercell.
C) roll cloud.
D) updraft.

Question 76

"Heat lightning":

A) is actually a display of the northern lights.
B) is brighter than ordinary lightning.
C) is also called "ball lightning."
D) is regular lightning occurring more than 20 kilometers from the person observing it.

Question 77

Tornadoes and midlatitude cyclones are similar in that:

A) both form in the trade- wind belt.
B) both have conspicuous surface fronts.
C) both are most common and well- developed in the winter season.
D) both circulate around low pressure.

Question 78

The greatest number of deaths associated with thunderstorms result from:

A) lightning.
B) flash flooding.
C) hail.
D) tornadoes.

Question 79

The Enhanced Fujita scale is based on:

A) the pressure gradient across the diameter of a tornado.
B) the measured wind speeds inside a tornado.
C) the level of damage caused by a tornado.
D) the frequency of lightning strikes concurrent with the tornado.

Question 80

In the United States, a mesoscale convective complex is most likely to develop in:

A) the Gulf of Mexico.
B) the Pacific Northwest.
C) the Great Plains.
D) New England.