weather

Question 1

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

Answer 1

air temperature.

Question 2

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

Answer 2

Clouds with considerable vertical development and associated turbulence.

Question 3

When may hazardous wind shear be expected?

Answer 3

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

Question 4

A pilot can expect a wind shear zone in a temperature inversion whenever the windspeed at 2,000 to 4,000 feet above the surface is at least

Answer 4

25 knots.

Question 5

What types of fog depend upon wind in order to exist?

Answer 5

Advection fog and upslope fog.

Question 6

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

Answer 6

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

Question 7

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

Answer 7

wind direction.

Question 8

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

Answer 8

terrestrial radiation on a clear, relatively still night.

Question 9

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

Answer 9

an increase in temperature as altitude increases.

Question 10

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

Answer 10

Precipitation beginning to fall.

Question 11

The mature stage of a thunderstorm begins with

Answer 11

the start of precipitation.

Question 12

Which weather phenomenon is always associated with a thunderstorm?

Answer 12

Lightning.

Question 13

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

Answer 13

Steam fog.

Question 14

What feature is associated with a temperature inversion?

Answer 14

A stable layer of air.

Question 15

When warm, moist, stable air flows upslope, it

Answer 15

produces stratus type clouds.

Question 16

Steady precipitation preceding a front is an indication of

Answer 16

stratiform clouds with little or no turbulence.

Question 17

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

Answer 17

heat exchange.

Question 18

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

Answer 18

squall line.

Question 19

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

Answer 19

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

Question 20

What clouds have the greatest turbulence?

Answer 20

Cumulonimbus.

Question 21

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

Answer 21

across a mountain ridge, and the air is stable.

Question 22

What would decrease the stability of an air mass?

Answer 22

Warming from below.

Question 23

Clouds, fog, or dew will always form when

Answer 23

water vapor condenses.

Question 24

In which situation is advection fog most likely to form?

Answer 24

An air mass moving inland from the coast in winter.

Question 25

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

Answer 25

unstable, moist air.

Question 26

The suffix ‘nimbus,’ used in naming clouds, means

Answer 26

a rain cloud.

Question 27

Which conditions result in the formation of frost?

Answer 27

The temperature of the collecting surface is at or below the dew point of the adjacent air and the dew point is below freezing.

Question 28

The wind at 5,000 feet AGL is southwesterly while the surface wind is southerly. This difference in direction is primarily due to

Answer 28

friction between the wind and the surface.

Question 29

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?

Answer 29

Step 1: 82°F (Surface temperature) – 38°F (Dew point) = 44°F
Step 2: 44 ÷ 4.4 = 10
Step 3: 10 × 1,000 = 10,000 feet AGL (base of cloud)

10,000 feet AGL. When lifted, unsaturated air cools at approximately 5.4°F per 1,000 feet. The dew point cools at approximately 1°F per 1,000 feet. Therefore, the convergence of the temperature and dew point lapse rates is 4.4°F per 1,000 feet. The base of a cloud (AGL) that is formed by vertical currents 10 3. 10 x 1,000 = 10,000 feet AGL

Question 30

Which type of weather briefing should a pilot request to supplement mass disseminated data?

Answer 30

An abbreviated briefing.

Question 31

What is indicated when a current Convective SIGMET forecasts thunderstorms?

Answer 31

Thunderstorms obscured by massive cloud layers

Question 32

To best determine general forecast weather conditions covering a flight information region, the pilot should refer to

Answer 32

Graphical Forecasts for Aviation (GFA).

Question 33

SIGMETs are issued as a warning of weather conditions hazardous to which aircraft?

Answer 33

All aircraft.

Question 34

When the term ‘light and variable’ is used in reference to a winds aloft forecast, the coded group and windspeed is

Answer 34

9900 and less than 5 knots.

Question 35

What information is contained in a Convective SIGMET?

Answer 35

Tornadoes, embedded thunderstorms, and hail 3/4 inch or greater in diameter.

Question 36

What should pilots state initially when telephoning Flight Service for preflight weather information?

Answer 36

Identify themselves as pilots.

Question 37

What values are used for winds aloft forecasts?

Answer 37

True direction and knots.

Question 38

AIRMETs are advisories of significant weather phenomena but of lower intensities than SIGMETs and are intended for dissemination to

Answer 38

all pilots.

Question 39

Which inflight advisory would contain information on severe icing not associated with thunderstorms?

Answer 39

SIGMET.