Aviation Weather Exam Solved Correctly
To Score A+ 2025!!
What are the characteristics of the flow of air around high pressure systems?
CORRECT ANSWERS Outward
Downward
Clockwise
What are the characteristics of the flow of air around low pressure systems? CORRECT
ANSWERS Inward
Upward
Counterclockwise
What is a Trough Line? CORRECT ANSWERS An elongated area of low pressure.
(Air rises in this area)
(It is conducive to cloudiness and precipitation)
What is a Ridge Line? CORRECT ANSWERS An elongated area of high pressure.
(Air moving out of a high depletes the quantity of air - therefore these are areas of
descending air.)
(Descending air favors dissipation of cloudiness)
What are isobars? CORRECT ANSWERS Lines on a weather chart which connect
areas of equal or constant barometric pressure.
If isobars are close together on a weather chart or a constant pressure chart what does
this mean? CORRECT ANSWERS This shows the steepness of the pressure gradient.
• Close = Steep Pressure Gradient = High Wind Speeds
• Spaced Out = Shallow PG = Low Wind Speeds
What causes the winds aloft to flow parallel to the isobars? CORRECT ANSWERS
Coriolis Force
What causes surface winds to generally flow across the isobars at an angle?
CORRECT ANSWERS Surface Friction
What is the effect of stable air on clouds? CORRECT ANSWERS Stratiform
What is the effect of unstable air on clouds? CORRECT ANSWERS Cumuliform
What is the effect of stable air on turbulence? CORRECT ANSWERS Smooth
What is the effect of unstable air on turbulence? CORRECT ANSWERS Rough
, What is the effect of stable air on precipitation? CORRECT ANSWERS Steady
What is the effect of unstable air on precipitation? CORRECT ANSWERS Showery
What is the effect of stable air on visibility? CORRECT ANSWERS Fair to Poor
What is the effect of unstable air on visibility? CORRECT ANSWERS Good
At what rate does atmospheric pressure decrease with an increase in altitude?
CORRECT ANSWERS 1in. Hg per 1,000 ft.
How do you determine the stability of the atmosphere? CORRECT ANSWERS By
observing the actual lapse rate and comparing it to the standard lapse rate of 3.5° F (2°
C) per 1000 ft.
(In general stable air cools at a rate less than the standard lapse rate with altitude)
The "K" index of a stability chart is the primary means of determining stability.
What are the stages of a thunderstorm? CORRECT ANSWERS 1. Cumulus - Updrafts
cause raindrops to increase in size
2. Mature - Rain at Earth's surface (it falls through or immediately beside the updrafts);
Lightning; perhaps roll clouds
3. Dissipating - Downdrafts and rain begin to dissipate
What factors must be present for thunderstorms to form? CORRECT ANSWERS 1. A
source of lift (heating, fast-moving front)
2. Unstable Air (nonstandard lapse rate)
3. High Moisture Content (temp. and dew point close)
Is frost considered hazardous to flight? CORRECT ANSWERS Yes.
(Because it causes friction... The friction interrupts the airflow that generates lift)
What action should be taken if you inadvertently encounter icing conditions? CORRECT
ANSWERS Change course and/or altitude. (Usually, climb to a higher altitude if
possible)
What are the main types of icing? CORRECT ANSWERS • Structural
• Induction
Name 4 types of structural Ice. CORRECT ANSWERS 1. Frost - Ice crystals from
sublimation when temp and dew point are below freezing
2. Clear - Large drops freeze slowly
3. Rime - Small drops freeze rapidly
4. Mixed - Supercooled drops varying in size
To Score A+ 2025!!
What are the characteristics of the flow of air around high pressure systems?
CORRECT ANSWERS Outward
Downward
Clockwise
What are the characteristics of the flow of air around low pressure systems? CORRECT
ANSWERS Inward
Upward
Counterclockwise
What is a Trough Line? CORRECT ANSWERS An elongated area of low pressure.
(Air rises in this area)
(It is conducive to cloudiness and precipitation)
What is a Ridge Line? CORRECT ANSWERS An elongated area of high pressure.
(Air moving out of a high depletes the quantity of air - therefore these are areas of
descending air.)
(Descending air favors dissipation of cloudiness)
What are isobars? CORRECT ANSWERS Lines on a weather chart which connect
areas of equal or constant barometric pressure.
If isobars are close together on a weather chart or a constant pressure chart what does
this mean? CORRECT ANSWERS This shows the steepness of the pressure gradient.
• Close = Steep Pressure Gradient = High Wind Speeds
• Spaced Out = Shallow PG = Low Wind Speeds
What causes the winds aloft to flow parallel to the isobars? CORRECT ANSWERS
Coriolis Force
What causes surface winds to generally flow across the isobars at an angle?
CORRECT ANSWERS Surface Friction
What is the effect of stable air on clouds? CORRECT ANSWERS Stratiform
What is the effect of unstable air on clouds? CORRECT ANSWERS Cumuliform
What is the effect of stable air on turbulence? CORRECT ANSWERS Smooth
What is the effect of unstable air on turbulence? CORRECT ANSWERS Rough
, What is the effect of stable air on precipitation? CORRECT ANSWERS Steady
What is the effect of unstable air on precipitation? CORRECT ANSWERS Showery
What is the effect of stable air on visibility? CORRECT ANSWERS Fair to Poor
What is the effect of unstable air on visibility? CORRECT ANSWERS Good
At what rate does atmospheric pressure decrease with an increase in altitude?
CORRECT ANSWERS 1in. Hg per 1,000 ft.
How do you determine the stability of the atmosphere? CORRECT ANSWERS By
observing the actual lapse rate and comparing it to the standard lapse rate of 3.5° F (2°
C) per 1000 ft.
(In general stable air cools at a rate less than the standard lapse rate with altitude)
The "K" index of a stability chart is the primary means of determining stability.
What are the stages of a thunderstorm? CORRECT ANSWERS 1. Cumulus - Updrafts
cause raindrops to increase in size
2. Mature - Rain at Earth's surface (it falls through or immediately beside the updrafts);
Lightning; perhaps roll clouds
3. Dissipating - Downdrafts and rain begin to dissipate
What factors must be present for thunderstorms to form? CORRECT ANSWERS 1. A
source of lift (heating, fast-moving front)
2. Unstable Air (nonstandard lapse rate)
3. High Moisture Content (temp. and dew point close)
Is frost considered hazardous to flight? CORRECT ANSWERS Yes.
(Because it causes friction... The friction interrupts the airflow that generates lift)
What action should be taken if you inadvertently encounter icing conditions? CORRECT
ANSWERS Change course and/or altitude. (Usually, climb to a higher altitude if
possible)
What are the main types of icing? CORRECT ANSWERS • Structural
• Induction
Name 4 types of structural Ice. CORRECT ANSWERS 1. Frost - Ice crystals from
sublimation when temp and dew point are below freezing
2. Clear - Large drops freeze slowly
3. Rime - Small drops freeze rapidly
4. Mixed - Supercooled drops varying in size
