Deck 6: Precipitation Extremes

Question 1

Which cloud type below will only produce precipitation by the collision-coalescence process?

A)a thick,cold nimbostratus cloud
B)a thick,warm cumulus cloud
C)a thick,cold cumulus cloud
D)a thick,supercooled cumulonimbus cloud with abundant nuclei
E)a supercooled cumulus congestus cloud

Answer 1

B

Question 2

Which type of precipitation would most likely form when the surface air temperature is slightly below freezing and the air temperature increases as you move upward away from the ground?

A)freezing rain
B)hail
C)rain
D)snow
E)drizzle

Answer 2

A

Question 3

If rain falls on one side of a street and not on the other side,the rain most likely fell from a(n):

A)nimbostratus cloud.
B)stratus cloud.
C)cumulonimbus cloud.
D)altostratus cloud.
E)altocumulus cloud.

Answer 3

C

Question 4

During the ice crystal process of rain formation:

A)only ice crystals need be present in a cloud.
B)ice crystals grow larger at the expense of the surrounding liquid cloud droplets.
C)the temperature in the cloud must be -40^o C (-40^o F)or below.
D)the cloud must be a cumuliform cloud.

Question 5

Which below best describes why a fluffy covering of snow is able to protect sensitive plants and their root systems from damaging low temperatures.

A)Snow is a good insulator.
B)Melting snow releases latent heat.
C)Snow is a good emitter of infrared energy.
D)Snow is a good reflector of sunlight.

Question 6

The difference in saturation vapor pressure between supercooled water and ice reaches a maximum at about -12^oC.This means that the ice crystal process will be most effective in producing precipitation when cloud temperatures are:

A)much colder than -12^oC.
B)around -12^oC.
C)much warmer than -12^oC.

Question 7

Radar gathers information about precipitation in clouds by measuring the:

A)energy emitted by the precipitation particles.
B)absorption characteristics of falling precipitation.
C)amount of energy reflected back to a transmitter.
D)amount of sunlight scattered off the precipitation.
E)amount of solar energy passing through the cloud.

Question 8

Which of the following is one reason that snow is more common in winter than in summer?

A)Precipitation falling from a cloud as snow has a better chance of surviving when temperatures are cold.
B)Very tall clouds are more common in winter than in summer.
C)Cumulonimbus clouds rarely occur in winter.
D)The atmosphere is usually more unstable in summer.

Question 9

Cumulus congestus clouds often produce drizzle.

Question 10

The main difference between a cloud drop and a raindrop is its:

A)color.
B)size.
C)shape.
D)none of the above

Question 11

In the winter you read in the newspaper that a large section of the Midwest is without power due to downed power lines.Which form of precipitation would most likely produce this situation?

A)snow
B)hail
C)freezing rain
D)sleet
E)rain

Question 12

At the same sub-freezing temperature,the saturation vapor pressure just above a liquid water surface is __________ the saturation vapor pressure above an ice surface.

A)greater than
B)the same as
C)less than

Question 13

If you observe large raindrops hitting the ground,you could probably say that the cloud overhead was __________ and had __________ updrafts.

A)thick,weak
B)thick,strong
C)thin,weak
D)thin,strong

Question 14

Supercooled cloud droplets are:

A)ice crystals surrounded by air warmer than 0 ^oC (32 ^oF).
B)liquid droplets that are cooler than the air around them.
C)liquid droplets observed at temperatures below 0 ^oC (32 ^oF).
D)water droplets that have had all their latent heat removed.

Question 15

A raindrop or partially melted snowflake that freezes into a pellet of ice in a deep subfreezing layer of air near the surface is called:

A)snow.
B)freezing rain.
C)sleet.
D)hail.
E)a snow pellet.

Question 16

Which of the following is not an important factor in the production of rain by the collision-coalescence process?

A)the updrafts in the cloud
B)relative size of the droplets
C)the number of ice crystals in the cloud
D)cloud thickness
E)the electric charge of the droplets

Question 17

Large,heavy snowflakes are associated with:

A)dry air and temperatures well below freezing.
B)moist air and temperatures well below freezing.
C)dry air and temperatures near freezing.
D)moist air and temperatures near freezing.

Question 18

After a rainstorm,visibility typically:

A)deteriorates.
B)is unaffected.
C)improves.

Question 19

Large raindrops fall __________ than smaller raindrops,and have a __________ terminal velocity than small raindrops.

A)faster,lesser
B)faster,greater
C)slower,lesser
D)slower,greater

Question 20

In a typical advancing winter storm,which of the following sequences of precipitation types is most likely to occur?

A)rain,freezing rain,snow,sleet
B)rain,sleet,freezing rain,snow
C)freezing rain,rain,sleet,snow
D)rain,freezing rain,sleet,snow

Question 21

The first raindrops to reach the ground at the beginning of a rain shower are often very large.Explain why this is so.

Question 22

It is never too cold to snow.

Question 23

Cloud seeding using silver iodide works well in warm clouds composed entirely of water droplets.

Question 24

The collision-coalescence process is most effective when clouds are made entirely of ice crystals.

Question 25

What is the main difference between a raindrop and a cloud droplet?

Question 26

Given that precipitation can be accurately measured at surface weather stations,explain why it is desirable to measure rainfall from space.

Question 27

Briefly describe the differences in the atmospheric temperature profiles necessary to produce snow,freezing rain,sleet,and hail.

Question 28

The growth of a precipitation particle by the collision of an ice crystal (or snowflake)with a supercooled liquid droplet is called deposition.

Question 29

A typical raindrop is slightly larger than a typical cloud droplet.

Question 30

Explain why it is much more difficult to measure snowfall amount than rainfall amount.

Question 31

In the midlatitudes,most rain results from melted snow that formed from the ice crystal process.

Question 32

Would you expect the heaviest snowfall to occur on an unusually cold night or a night when the temperature was just a little below freezing?

Question 33

In warm clouds,the cloud droplets are usually all the same size.

Question 34

Thunderstorm cloud bases are generally higher above the ground in Arizona than in Florida.Why?

Question 35

Would you expect the largest forms of precipitation particles to occur during the warmest or the coldest time of year? Explain.

Question 36

Rain which falls from a cloud,but evaporates before reaching the ground is called virga.

Question 37

Explain why it is possible for an ice crystal to grow in a cold cloud even though the supercooled water droplets surrounding the ice crystal do not.

Question 38

Design an automated device for measuring snowfall.How might it work?

Question 39

What locations receive the most precipitation on the earth? What weather conditions cause this excessive precipitation?

Question 40

Ice crystals,clay minerals,and bacteria from decaying plant material can all serve as ice nuclei.