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Convective circulation patterns associated with sea breezes are caused by - Answer-
Cool, dense air moving inland from over the water.
The wind at 5,000 feet AGL is southwesterly while the surface wind is southerly. This
difference in direction is primarily due to - Answer- Friction between the wind and the
surface.
One weather phenomenon which will always occur when flying across a front is a
change in the - Answer- Wind direction.
One of the most easily recognized discontinuities across a front is - Answer- A change
in temperature.
What feature is associated with a temperature inversion? - Answer- A stable layer of air.
A stable air mass is most likely to have which characteristic? - Answer- Poor surface
visibility.
What is a characteristic of stable air? - Answer- Stratiform clouds.
What are characteristics of unstable air? - Answer- Turbulence and good surface
visibility.
What would decrease the stability of an air mass? - Answer- Warming from below.
What are characteristics of a moist, unstable air mass? - Answer- Cumuliform clouds
and showery precipitation.
Which weather conditions should be expected beneath a low-level temperature
inversion layer when the relative humidity is high? - Answer- Smooth air, poor visibility,
fog, haze, or low clouds.
What measurement can be used to determine the stability of the atmosphere? -
Answer- Actual lapse rate.
Clouds are divided into four families according to their - Answer- Height range.
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? - Answer- 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? -
Answer- 10,000 feet AGL.
When warm, moist, stable air flows upslope, it - Answer- Produces stratus-type clouds.
The suffix "nimbus," used in naming clouds, means - Answer- A rain cloud.
If an unstable air mass is forced upward, what type clouds can be expected? - Answer-
Clouds with considerable vertical development and associated turbulence.
The conditions necessary for the formation of cumulonimbus clouds are a lifting action
and - Answer- Unstable, moist air.
Steady precipitation preceding a front is an indication of - Answer- Stratiform clouds with
little or no turbulence.
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- 25 knots.
When may hazardous wind shear be expected? - Answer- In areas of low-level
temperature inversion, frontal zones, and clear air turbulence.
Where does wind shear occur? - Answer- At all altitudes, in all directions
The amount of water vapor which air can hold depends on the - Answer- air
temperature
Clouds, fog, or dew will always form when - Answer- water vapor condenses
What should pilots state initially when telephoning Flight Service for preflight weather
information? - Answer- The intended route of flight and destination
Every physical process of weather is accompanied by, or is the result of, a - Answer-
heat exchange
What causes variations in altimeter settings between weather reporting points? -
Answer- Unequal heating of the Earth's surface
When there is a temperature inversion, you would expect to experience - Answer- an
increase in temperature as altitude increases
The most frequent type of ground or surface-based temperature inversion is that which
is produced by - Answer- terrestrial radiation on a clear, relatively still night