Fundamentals Of WX

Question 1

At what rate does atmospheric pressure decrease with altitude?

Answer 1

Atmospheric pressure decreases approximately 1” Hg per 1,000 feet.

Question 2

What are the standard temperature and pressure values at sea level?

Answer 2

15°C and 29.92” Hg.

Question 3

How does air flow around low-pressure systems in the northern hemisphere?

Answer 3

Inward, upward, and counterclockwise.

Question 4

How does air flow around high-pressure systems in the northern hemisphere?

Answer 4

Outward, downward, and clockwise.

Question 5

What general weather is associated with low-pressure systems?

Answer 5

Cloudiness, precipitation, and bad weather due to rising air.

Question 6

What general weather is associated with high-pressure systems?

Answer 6

Clear skies and good weather due to descending air.

Question 7

**What weather conditions are commonly encountered near a cold front?
**

• T.
• H.
• P.
• G.

You can remember it as “The Happy Penguins Glide” to make it a bit more fun!

Answer 7

* Towering cumulus or cumulonimbus clouds
* Heavy rain
* Poor visibility
* Gusting winds**

Question 8

What weather conditions are commonly encountered near a warm front?

You can remember it as “Silly Ducks Love Playing Violins” to make it a bit more fun!

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V

Answer 8

Stratiform clouds

Drizzle

Low ceilings

Poor visibility

Variable winds

Question 9

What is a cold front?

Answer 9

A cold, dense air mass advancing and replacing a warmer air mass.

Question 10

What is an occluded front?

Answer 10

A fast-moving cold front catching up with a slow-moving warm front.

Question 11

What is a warm front?

Answer 11

A warm air mass contacts and flows over a colder air mass.

Question 12

What is a stationary front?

Answer 12

A boundary between two air masses that remains stationary, often resulting in mixed weather.

Question 13

What is a trough in meteorology?

Answer 13

An elongated area of low pressure associated with rising air, cloudiness, and precipitation.

Question 14

What is a ridge in meteorology?

Answer 14

An elongated area of high pressure associated with descending air and good weather.

Question 15

What is a dryline and why is it important?

Answer 15

A dryline is a boundary separating moist and dry air masses. Severe thunderstorms often develop along or near it.

Question 16

Why do surface winds flow across isobars at an angle?

Answer 16

Surface friction causes winds to flow across isobars at an angle.

Question 17

When temperature and dew point are close together, what weather is likely?

Answer 17

Visible moisture such as clouds, dew, or fog.

Question 18

What factor primarily determines the type and vertical extent of clouds?

Answer 18

The stability of the atmosphere.

Question 19

How does atmospheric stability affect vertical air movement?

Answer 19

A stable atmosphere resists vertical movement, while an unstable atmosphere promotes it, leading to turbulence.

Question 20

How do you determine atmospheric stability?

Answer 20

By observing temperature lapse rates; steeper lapse rates indicate less stability.

Question 21

What are the effects of stable air on clouds, turbulence, precipitation, and visibility?

Answer 21

Stable air: stratiform clouds, smooth air, steady precipitation, poor visibility.

Question 22

What are the effects of unstable air on clouds, turbulence, precipitation, and visibility?

Answer 22

Unstable air: cumuliform clouds, rough air, showery precipitation, good visibility.

Question 23

What are the two main categories of aircraft icing?

Answer 23

Structural icing and induction icing.

Question 24

What are the three types of structural ice that may occur in flight?

Answer 24

Clear ice, rime ice, and mixed ice.

Question 25

What is clear ice, and under what conditions does it form?

Answer 25

Clear ice is glossy, translucent ice formed by slow freezing of large droplets in warmer conditions.

Question 26

What is rime ice, and under what conditions does it form?

Answer 26

Rime ice is rough, opaque ice formed by the rapid freezing of small droplets in colder conditions.

Question 27

What is mixed ice, and how does it form?

Answer 27

Mixed ice is a combination of clear and rime ice, forming under intermediate conditions.

Question 28

What types of icing are found in stratiform clouds?

Answer 28

Rime and mixed ice, typically in layers 3,000 to 4,000 feet thick.

Question 29

What types of icing are found in cumuliform clouds?

Answer 29

Clear or mixed ice, usually concentrated in the upper levels.

Question 30

What conditions are necessary for structural icing to occur?

Answer 30

Visible water and temperatures at or below 0°C.

Question 31

What are the intensity categories of aircraft structural icing?

Answer 31

Trace, light, moderate, and severe.

Question 32

What characterizes 'trace' aircraft structural icing?

Answer 32

Ice is noticeable, but the accumulation rate is slightly greater than sublimation.

Question 33

What characterizes 'light' aircraft structural icing?

Answer 33

Ice accumulates at ¼ to 1 inch per hour, requiring occasional deicing.

Question 34

What characterizes 'moderate' aircraft structural icing?

Answer 34

Ice accumulates at 1 to 3 inches per hour, requiring frequent deicing.

Question 35

What characterizes 'severe' aircraft structural icing?

Answer 35

Ice protection systems fail to remove ice; accumulation exceeds 3 inches per hour.

Question 36

What meteorological information should you check preflight to avoid icing?

Answer 36

Front locations, cloud layers, freezing levels, temperatures, and precipitation.

Question 37

What is the definition of 'freezing level'?

Answer 37

The lowest altitude where the air temperature reaches 0°C.

Question 38

How can you determine the freezing level location?

Answer 38

Use GFA, PIREPs, AIRMETs, SIGMETs, and other aviation weather products.

Question 39

How can you mitigate the risk of operating in or near icing conditions during preflight planning?

Answer 39

Consider climb performance, icing exit strategies, fuel requirements, and alternate airports with longer runways.

Question 40

What factors are necessary for a thunderstorm to form?

Answer 40

Sufficient water vapor, an unstable lapse rate, and an initial upward lift.

Question 41

What are the three stages of thunderstorm development?

Answer 41

Cumulus (updrafts), mature (precipitation, updrafts, and downdrafts), and dissipating (downdrafts).

Question 42

What is a squall line?

Answer 42

A non-frontal narrow band of active thunderstorms, often severe, usually forming ahead of a cold front.

Question 43

How does fog form?

Answer 43

Fog forms when the temperature and dew point become identical or nearly identical.

Question 44

What are several types of fog?

Answer 44

Radiation, advection, upslope, frontal (precipitation-induced), and steam fog.

Question 45

What causes radiation fog to form?

Answer 45

Clear skies, little or no wind, and high humidity at night or near daybreak.

Question 46

What is advection fog, and where is it most likely to form?

Answer 46

Advection fog forms when moist air moves over colder ground or water, common in coastal areas.

Question 47

What causes upslope fog to form?

Answer 47

Moist, stable air moving up sloping terrain and cooling adiabatically.

Question 48

What is steam fog, and how does it form?

Answer 48

Steam fog forms when cold air moves over warmer water, causing rising moisture to condense into fog.

Question 49

How does frontal (precipitation-induced) fog form?

Answer 49

Warm, moist air lifted over a front causes precipitation; evaporation saturates cold air near its dew point, forming fog.

Question 50

What are some common IFR weather producers besides fog?

Answer 50

Low clouds (stratus), haze, smoke, blowing obstructions, and precipitation.

Question 51

How can you obtain a good weather briefing prior to a flight?

Answer 51

Watch weather forecasts, use Flight Service, download weather charts, and get a standard briefing close to departure.

Question 52

What are some examples of other sources of weather information?

Answer 52

Leidos Flight Services, private industry sources, and FIS-B via ADS-B In.

Question 53

What should a weather briefing include?

Answer 53

Adverse conditions, VFR not recommended, synopsis, current conditions, forecasts, winds aloft, NOTAMs, ATC delays.

Question 54

How can a pilot obtain updated weather information while en route?

Answer 54

Contact FSS, use ATIS/ASOS/AWOS, datalink weather, or ask ATC.

Question 55

What is Flight Information Service–Broadcast (FIS-B)?

Answer 55

A service that provides aviation weather and aeronautical information via ADS-B to properly equipped aircraft.