FAA PPL Test Prep: Ch. 6: Weather

Every physical process of weather is accompanied by, or is a result of a

A. Movement of air
B. Pressure differential
C. Heat exchange

C. Heat exchange

What causes variations in altimeter settings between weather reporting points?

A. Unequal heating of the earth's surface
B. Variation of terrain elevation
C. Coriolis force

A. Unequal heating of the earth's surface

The wind at 5000 feet AGL is southwesterly while the surface wind is southerly. This difference in direction is primarily due to

A. Stronger pressure Gradient at higher altitudes
B. Friction between the wind and the surface
C. Stronger Coriolis force at the surface

B. Friction between the wind and the surface

Convective circulation patterns association with sea breeze are caused by

A. Warm dense air moving inland from over the water
B. Water absorbing the radiating heat faster than the land
C. Cool, dence air moving inland from over the water

C. Cool, dence air moving inland from over the water

When there is a temperature inversion, you would expect to experience

A. Clouds with extensive vertical development above an inversion aloft
B. Good visibility in the lower levels of the atmosphere and poor visibility above an inversion aloft
C. An increase in temperature as altitude increases

C. An increase in temperature as altitude increases

The most frequent type of ground or surface-based temperature inversion is that which is produced by

A. Terrestrial radiation on a clear, relatively still night
B. Warm air being lifted rapidly aloft in the vicinity of mountainous terrain
C. The movement of colder air under warm air, or the movement of warm air over cold air

A. Terrestrial radiation on a clear, relatively still night

What feature is associated with a temperature inversion?

A. A stable layer of air
B. An unstable layer of air
C. Chinook winds on mountain slopes

A. A stable layer of air

One weather phenomenon which will always occur when flying across front is a change in the

A. Wind direction
B. Type of perception
C. Stability of the air mass

A. Wind direction

One of the most easily recognized discontinuities across a front is

A. A change in temperature
B. An increase in cloud coverage
C. An increase in relative humidity

A. A change in temperature

Which weather conditions should be expected beneath a low-level temperature inversion layer when relative humidity is high?

A. Smooth air, poor visibility, fog, haze, or low clouds
B. Light wind shear, poor visibility, haze, and light rain
C. Turbulent air, poor visibility, fog, low stratus type clouds, and showery precipitation

A. Smooth air, poor visibility, fog, haze, or low clouds

What measurement can be used to determine the stability of the atmosphere?

A. Atmospheric pressure
B. Actual lapse rate
C. Surface temperature

B. Actual lapse rate

What would decrease the stability of an air mass?

A. Warming from below.
B. Cooling from below.
C. Decrease in water vapor.

C. Decrease in water vapor.

What is a characteristic of stable air?

A. Stratiform clouds
B. Unlimited visibility
C. Cumulus clouds

A. Stratiform clouds

What are characteristics of a moist, unstable air mass?

A. Cumuliform clouds and showery precipitation
B. Poor visibility and smooth air
C. Stratiform clouds and showery precipitation

A. Cumuliform clouds and showery precipitation

What are characteristics of unstable air?

A. Turbulence and good surface visibility
B. Turbulence and poor surface visibility
C. Nimbostratus clouds and good surface visibility

A. Turbulence and good surface visibility

A stable air mass is most likely to have which characteristic?

A. Showery precipitation
B. Turbulent air
C. Poor surface visibility

C. Poor surface visibility

When warm, moist, stable air flows upslope, it

A. Produces stratus type clouds
B. Causes showers and thunderstorms
C. Develops convective turbulence

A. Produces stratus type clouds

If an unstable air mass is forced upward, what type clouds can be expected?

A. Stratus clouds with little vertical development
B. Stratus clouds with considerable associated turbulence
C. Clouds with considerable vertical development and associated turbulence

C. Clouds with considerable vertical development and associated turbulence

Steady precipitation preceding a front is an indication of

A. Stratiform clouds with moderate turbulence
B. Cumuliform clouds with little or no turbulence
C. Stratiform clouds with little or no turbulence

C. Stratiform clouds with little or no turbulence

The conditions necessary for the formation of cumulonimbus clouds are a lifting action and

A. unstable air containing an excess of condensation nuclei
B. unstable, moist air
C. either stable or unstable air

B. unstable, moist air

What is the approximate base of the cumulus clouds if the surface air temperature at 1,000 feet MSL is 70 F and the dew point is 48 F?

A. 4,000 feet MSL
B. 5,000 feet MSL
C. 6,000 feet MSL

C. 6,000 feet MSL

At approximately what altitude above the surface would the pilot expect the base of cumuliform clouds if the surface air temperature is 82 F and the dew point is 38 F?

A. 9,000 feet AGL
B. 10,000 feet AGL
C. 11,000 feet AGL

B. 10,000 feet AGL

The suffix "nimbus," used in naming clouds, means

A. a cloud with extensive vertical development.
B. a rain cloud.
C. a middle cloud containing ice pellets.

B. a rain cloud.

Clouds are divided into four families according to their

A. outward shape
B. height range
C. composition

B. height range

What clouds have the greatest turbulence?

A. Towering cumulus
B. Cumulonimbus
C. Nimbostratus

B. Cumulonimbus

Upon encountering severe turbulence, which flight condition should the pilot attempt to maintain?

A. Constant altitude and airspeed
B. Constant angle of attack
C. Level flight attitude

C. Level flight attitude

If there is thunderstorm activity in the vicinity of an airport at which you plan to land, which hazardous atmospheric phenomenon might be expected on the landing approach?

A. Precipitation static
B. Wind-shear turbulence
C. Steady rain

B. Wind-shear turbulence

A nonfrontal, narrow band of active thunderstorms that often develop ahead of a cold front is known as a

A. Prefrontal system
B. Squall line
C. Dry line

B. Squall line

What conditions are necessary for the formation of thunderstorms?

A. High humidity, lifting force, and unstable conditions
B. High humidity, high temperatures, and cumulus clouds
C. Lifting force, moist air, and extensive cloud cover

A. High humidity, lifting force, and unstable conditions

During the life cycle of a thunderstorm, which stage is characterized predominantly by downdrafts?

A. Cumulus
B. Dissipating
C. Mature

B. Dissipating

Thunderstorms reach their greatest intensity during the

A. Mature stage
B. Downdraft stage
C. Cumulus stage

A. Mature stage

What feature is normally associated with the cumulus stage of a thunderstorm?

A. Role cloud
B. Continuous updraft
C. Frequent lightning

B. Continuous updraft

Which weather phenomenon signals the beginning of the mature stage of a thunderstorm?

A. The appearance of an anvil top
B. Precipitation beginning to fall
C. Maximum growth rate of the clouds

B. Precipitation beginning to fall

Thunderstorms which generally produce the most intense hazard to aircraft are

A. Squall line thunderstorms
B. Steady state thunderstorms
C. Warm front thunderstorms

A. Squall line thunderstorms

Which weather phenomenon is always associated with a thunderstorm?

A. Lightning
B. Heavy rain
C. Hail

A. Lightning

The mature stage of a thunderstorm begins with

A. Formation of the anvil top
B. The start of precipitation
C. Continuous downdrafts

B. The start of precipitation

During a cross-country flight you picked up rime icing which you estimate is 1/2" thick on the leading edge of the wings. You are now below the clouds at 2,000 feet AGL and are approaching your destination airport under VFR. Visibility under the clouds is more than 10 miles, winds at the destination airport are 8 knots right down the runway, and the surface temperature is 3 degrees Celsius. You decide to:

A. Use a faster than normal approach and landing speed
B. Approach and land at your normal speed since the ice is not thick enough to have any noticeable effect
C. Fly your approach slower than normal to lessen the wind chill effect and break up the ice

A. Use a faster than normal approach and landing speed

One in-flight condition necessary for structural icing to form is

A. A small temperature/dewpoint spread
B. Stratiform clouds
C. Visible moisture

C. Visible moisture

In which environment is aircraft structural ice most likely to have the highest accumulation rate?

A. Cumulus clouds with below freezing temperatures
B. Freezing drizzle
C. Freezing rain

C. Freezing rain

The presence of ice pellets at the surface is evidence that there

A. Are thunderstorms in the area
B. Has been cold frontal passage
C. Is a temperature inversion with freezing rain at a higher altitude

C. Is a temperature inversion with freezing rain at a higher altitude

An almond or lens shaped cloud which appears stationary but which may contain winds of 50 knots or more is referred to as

A. An inactive frontal cloud
B. A funnel cloud
C. A lenticular cloud

C. A lenticular cloud

Crests of standing mountain waves may be marked by stationary, lens-shaped clouds known as

A. Mammatocumulus clouds
B. Standing lenticular clouds
C. Roll clouds

B. Standing lenticular clouds

What clouds types would indicate convective turbulence?

A. Cirrus clouds
B. Nimbostratus clouds
C. Towering cumulus clouds

C. Towering cumulus clouds

Possible mountain wave turbulence could be anticipated when winds are 40 knots or greater blow

A. Across a mountain ridge and the air is stable
B. Down a mountain valley and the air is unstable
C. Parallel to a mountain peak and the air is stable

A. Across a mountain ridge and the air is stable

Where does wind shear occur?

A. Only at higher altitudes
B. Only at lower altitudes
C. At all altitudes in all directions

C. At all altitudes in all directions

A pilot can expect a wind shear zone in a temperature inversion whenever the wind speed at 2000 to 4000 feet above the surface is at least

A. 10 knots
B. 15 knots
C. 25 knots

C. 25 knots

When may hazardous wind shear be expected

A. When stable air crosses a mountain barrier where it tends to flow in layers forming lenticular clouds.
B. In areas of low level temperature inversion frontal zones and clear air turbulence
C. Following frontal passage when stratocumulus clouds form indicating mechanical mixing

B. In areas of low level temperature inversion frontal zones and clear air turbulence

If the temperature/dewpoint is spread is small and decreasing and the temperature is 62F what type of weather is most likely to develop?

A. Freezing precipitation
B. Thunderstorms
C. Fog or low clouds

C. Fog or low clouds

What is meant by the term dewpoint?

A. The temperature at which condensation and evaporation are equal
B. The temperature at which dew will always form
C. The temperature to which air must be cooled to become saturated

C. The temperature to which air must be cooled to become saturated

The amount of water vapor which air can hold depends on the

A. Dewpoint
B. Air temperature
C. Stability of the air

B. Air temperature

What are the processes by which moisture is added to unsaturated air?

A. Evaporation and sublimation
B. Heating and condensation
C. Supersaturation and evaporation

A. Evaporation and sublimation

Which conditions result in the formation of frost?

A. The temperature of the collecting surface is at or below freezing when small droplets of moisture fall on the surface
B. The temperature of the collecting surface is at or below the dewpoint of the adjacent air and the dewpoint is below freezing
C. The temperature of the surrounding air is at or below freezing when small drops of moisture fall on the collecting surface

B. The temperature of the collecting surface is at or below the dewpoint of the adjacent air and the dewpoint is below freezing

Clouds, fog, or dew will always form when

A. Water vapor condenses
B. Water vapor is present
C. Relative humidity reaches 100 percent

A. Water vapor condenses

In which situation is advection fog most likely to form

A. A warm, moist air mass on the windward side of the mountains
B. An air mass moving inland from the coast in winter
C. A light breeze blowing colder air out to sea

B. An air mass moving inland from the coast in winter

What situation is the most conductive to the formation of radiation fog?

A. Warm, moist air over low, flatland areas on clear, calm nights
B. Moist, tropical air moving over cold, offshore water
C. The movement of cold ait over much warmer water

A. Warm, moist air over low, flatland areas on clear, calm nights

What types of fog depend upon wind in order to exist

A. Radiation fog and ice fog
B. Steam fog and ground fog
C. Advection fog and upslope fog

C. Advection fog and upslope fog

Low-level turbulence can occur and icing can become hazardous in which type of fog?

A. Rain-induced fog
B. Upslope fog
C. Steam fog

C. Steam fog

How does frost affect the lifting surfaces of an airplane on takeoff?

A. Frost may prevent the airplane from becoming airborne at normal takeoff speed
B. Frost will change the camber of the wing, increasing lift during takeoff
C. Frost may cause the airplane to become airborne with a lower angle of attack at a lower indicated airspeed

A. Frost may prevent the airplane from becoming airborne at normal takeoff speed

How will frost on the wings of an airplane affect takeoff performance?

A. Frost will disrupt the smooth flow of air over the wing, adversely affecting its lifting capability
B. Frost will change the camber of the wing, increasing its lifting capability
C. Frost will cause the airplane to become airborne with a higher angle of attack, decreasing the stall speed

A. Frost will disrupt the smooth flow of air over the wing, adversely affecting its lifting capability

Why is frost considered hazardous to flight?

A. Frost changes the basic aerodynamic shape of the airfoils, thereby increasing lift.
B. Frost slows the airflow over the airfoils, thereby increasing control effectiveness.
C. Frost spoils the smooth flow of air over the wings, thereby decreasing lifting capability

C. Frost spoils the smooth flow of air over the wings, thereby decreasing lifting capability