Air Mass- extremely large body of air whose properties of temperature and moisture are
fairly similar in any horizontal direction.
Low Pressure System- air mass system with generally cloudy and rainy weather which
spins counter-clockwise in the northern hemisphere.
High Pressure System- air mass system that is generally cool with clear skies with winds
blowing outward in a clockwise fashion in the northern hemisphere.
Isobars- lines of equal pressure.
Winds are always named by the direction they blow FROM.