Temperaturre inversions result in which weather conditions?
An increase in Temperature as altitude is increased.
What are characteristics of a moist, unstable air mass?
Cumuliform clouds and showery precipitation.
Upon encountering sever turbulence, which flight condition should the pilot attempt to maintain
Level flight altitude
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 spread is 48F?
6000 feet MSL
Exp. When lifted, unsaturated air cools at approximately 5.4 F per 1,000 feet. The dew point cools at approximately 1F per 1000feet. Therefore, the convergence of the temperature and dew point lapse rates is 4.4F per 1000feet. The base of the cloud that is formed by vertical currents can be can be calculated by dividing the difference between the surface temp and the dew point by 4.4 and mult the rounded result by 1,000.
Formula base of cumulus clouds
Surface temperature -dew point=22F
22 divided by 4.4=5
5 X 1,000=5000 AGL
5000 feet AGL + 1000 feet field elevation=6000
The wind at 5000 feet AGL is southwesterly while the surface wind is southerly. This difference in direction is primarily due to
Friction between the wind and the surface
The most frequent type of ground or surface based temperature inversion is that which is produced by
terrestrial radiation on a clear, relatively still night.
Presence of ice pellets at the surface is evidence that there
is a temperature inversion with freezing rain at a higher altitude
Convective circulation patterns associated with sea breezes are caused by
Cool, dense air moving inland from over the water.
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
If the Temperature/dew point spread is small and decreasing, and the temperature is 62F, what type weather is most likely to develop?
Fog or low clouds.
If there is TS activity in the vicinity of an airport at which you plan to land, which hazardous atmospheric phenomenon might be expected on the landing approach?
Results in formation of frost
The temperature of the collecting surface is at or below the dew point of the adjacent air and the dew point is below freezing
A non frontal, narrow band of active TSs that often develop ahead of a cold front is known as a
What is meant by the term "dew point"
the temperature to which air must be cooled to become saturated
Crests of standing mountain waves may be marked by stationary, lens-shaped clouds known as
standing lenticular clouds
Steady precipitation preceding a front is an indication of
stratiform clouds with little or no turbulence.
If an unstable air mass is forced upward, what type clouds can be expected?
Clouds with considerable vertical development and associated turbulence.
What conditions are necessary for the formation of TS
High humidity, lifting force, and unstable conditions.
How does frost affect the lifting surfaces of an airplane on takeoff?
Frost may prevent the airplane from becoming airborne at normal takeoff speed.
At approximately what alt above surface would the pilot expect the base of a cumuliform clouds if the surface air temperature is 82F and the dew point is 38F?
1000 feet AGL
Frost on the wings will affect take off performance
disrupting the smooth flow of air over the wing, adversely affecting its lifting capability.
Frost is considered hazardous to flight because
Frost spoils the smooth flow of air over the wings, thereby decreasing lifting capability.
Conductive to the formation of radiation fog
Warm, moist air over low, flatland areas on clear, calm nights.
Possible mountain wave turbulence could be anticipated when winds of 40 knots or greater blow
across a mountain ridge, and the air is stable.
Which weather conditions should be expected beneath a low-level temperature inversion layer when the relative humidity is high?
Smooth air, poor vis, fog, haze, or low clouds.
Weather phenomenon signals the beginning of the mature stage of a TS
Precipitation beginning to fall
An almond or lens-shaped cloud wich appears stationary, but which may contain winds of 50 knots or more, is referred to as
One weather phenomenon which will always occur when flying across a front is a change in the
Hazardous wind shear can be expected
in areas of low level temperature inversion, frontal zones, and clear air turbulence.
The conditions necessary for the formation of cumulonimbus clouds are a lifting action and
unstable, moist air.
What causes variations in altimeter settings between weather reporting points?
Unequal heating of the Earth's surface