100%
The condition of the atmosphere at any given moment of time
weather
If the absolute humidity of the air is 15 g/m3, but 25 g/m3 would saturate the air at this temperature. What is the relative humidity?
60%
What global wind system affects weather movement the most in the United States?
prevailing westerlies
Name for fluffy, high level clouds.
cirrocumulus
If water vapor contacts a surface whose dewpoint is below freezing, what forms on the surface?
frost
the study or science of the atmosphere
meteorology
The most important factor in the development of a regional wind?
the pressure gradient between the high and the low pressure zones
When would you expect the winds to be calm if vacationing at the beach?
dawn and sunset
What's wrong with naming a cloud "altocirrus"?
alto means mid-level; cirrus means high level.
A device used to measure humidity.
Hygrometer or Psychrometer
what are the two reference points of both the Celsius and Fahrenheit temperature scales
the boiling point and freezing point of pure water
What causes winds to deflect as they blow over long distances?
the Coriolis effect
For clouds to form in an air mass, what two conditions must be met?
the air must be below its dew point, and condensation nuclei must be present.
How much bigger is a raindrop than a cloud droplet?
100 times bigger
A device used to measure wind velocities.
anemometer
Toward what direction is an east wind blowing?
west
What factor doesn't affect high altitude winds as much as surface winds?
Friction
Why do air masses cool as they rise into the atmpshere?
Their particles expand and use energy for the expansion.
What's the difference between freezing rain and sleet?
Sleet falls as frozen pellets of ice. Freezing rain freezes when it hits the ground.
the device used to measure atmospheric pressure.
barometer
a weather vane points toward 225 degrees. what is the direction by compass point?
a southwesterly (SW) wind
What direction would regional winds at 20 degrees S tend to blow towards?
the West
How can super cooled water be a problem?
It can freeze on airplane surfaces.
What forms when a frozen raindrop rises and falls repeatedly through a vertical cloud?
Hailstones
the device used to measure liquid precipitation amounts.
rain gauge