weather Flashcards
(40 cards)
The amount of water vapor which air can hold depends on the
air temperature.
If an unstable air mass is forced upward, what type clouds can be expected?
Clouds with considerable vertical development and associated turbulence.
When may hazardous wind shear be expected?
In areas of low-level temperature inversion, frontal zones, and clear air 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
25 knots.
What types of fog depend upon wind in order to exist?
Advection fog and upslope fog.
What situation is most conducive to the formation of radiation fog?
Warm, moist air over low, flatland areas on clear, calm nights.
One weather phenomenon which will always occur when flying across a front is a change in the
wind direction.
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.
When there is a temperature inversion, you would expect to experience
an increase in temperature as altitude increases.
Which weather phenomenon signals the beginning of the mature stage of a thunderstorm?
Precipitation beginning to fall.
The mature stage of a thunderstorm begins with
the start of precipitation.
Which weather phenomenon is always associated with a thunderstorm?
Lightning.
Low-level turbulence can occur and icing can become hazardous in which type of fog?
Steam fog.
What feature is associated with a temperature inversion?
A stable layer of air.
When warm, moist, stable air flows upslope, it
produces stratus type clouds.
Steady precipitation preceding a front is an indication of
stratiform clouds with little or no turbulence.
Every physical process of weather is accompanied by, or is the result of, a
heat exchange.
A nonfrontal, narrow band of active thunderstorms that often develop ahead of a cold front is known as a
squall line.
Which weather conditions should be expected beneath a low-level temperature inversion layer when the relative humidity is high?
Smooth air, poor visibility, fog, haze, or low clouds.
What clouds have the greatest turbulence?
Cumulonimbus.
Possible mountain wave turbulence could be anticipated when winds of 40 knots or greater blow
across a mountain ridge, and the air is stable.
What would decrease the stability of an air mass?
Warming from below.
Clouds, fog, or dew will always form when
water vapor condenses.
In which situation is advection fog most likely to form?
An air mass moving inland from the coast in winter.