Card Set Information
What is a feature of air movement in a high pressure area?
Descending to the surface then outward
Where is the usual location of a thermal low?
Over the surface of a dry, sunny region
What temperature condition is indicated if precipitation in the form of wet snow occurs during flight?
The temperature is above freezing at Flight altitude
Where is a common location for an inversion?
In the stratosphere
Which term applies when the temperature of the air changes by compression or expansion with no heat added or removed?
Isobars on a surface weather chart represent lines of equal pressure
Reduced to sea level
At which location does Coriolis force have the least effect on wind direction?
At the equator
How does Coriolis force affect wind direction in the Southern Hemisphere?
Causes clockwise rotation around a low
Which weather condition is defined as an anti-cyclone?
High pressure area
What is the result when water vapor changes to the liquid state while being lifted in a thunderstorm?
Latent heat is released into the atmosphere
What is a feature of supercooled water?
The unstable water drop freezes upon striking an exposed object
Which process causes adiabatic cooling?
Expansion of air as it rises
When saturated air moves downhill, its temperature increases
at a slower rate than dry air because vaporization releases latent heat
What minimum thickness of cloud layer is indicated if precipitation is reported as light or greater intensity?
Which condition produces weather on the lee side of a large lake?
Warm air flowing over a colder lake may produce fog
How can the stability of the atmosphere be determined?
Ambient temperature lapse rate
Atmospheric pressure changes due to a thunderstorm will be at the lowest value
When the thunder storm is approaching
Why are downdrafts in a mature thunderstorm hazardous?
Downdrafts are kept cool by cold rain which tends to accelerate the downward velocities
What is a difference between an air mass thunderstorm and a steady-state thunderstorm?
Air mass thunderstorm downdrafts and precipitation retard the reverse of the updrafts
Which type storms are most likely to produce funnel clouds or tornadoes?
Cold front or squall line thunderstorms
What type weather change is to be expected in an area where frontolysis is reported?
The front is dissipating
Which weather condition is an example of a nonfrontal instability band?
In which meteorological conditions can frontal waves and low pressure areas form?
Slow moving cold front or stationary fronts
Under what conditions would clear air turbulence (CAT) most likely be encountered?
When constant pressure charts show 20 knot isotachs less then 60 MN apart
What action is recommended when encountering turbulence due to a wind shift associated with a sharp pressure trough?
Establish a straight course through the troff
Which type frontal system is normally crossed by the Jetstream?
Which action is recommended regarding an altitude change to get out of jetstream turbulence?
Descend if ambient temperature is falling
Clear air turbulence (CAT) associated with a mountain wave may extend as far as
5000 feet above the tropopause
A strong wind shear can be expected
On the low pressure side of a 100 knot jet stream core