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d. Additional complications in the general circulation of the air are brought about by: the
irregular distribution of oceans and continents, the difference in how different surfaces transfer heat
to the atmosphere, the daily variation in temperature, the seasonal changes, and many other factors.
The general flow of weather in the United States is from northwest to southeast.
3. Lows

Regions of low pressures develop where air lies over land or water surfaces that are warmer than the

surrounding areas. Lows form over the desert southwest of the United States during the summer
months.

4. Highs

Regions of high pressure develop where the air lies over surfaces that are cooler than the surrounding

areas, such as polar regions, and where air traveling from the equator to the poles is forced to
descend.

5. Wind Patterns

Wind flows from high pressure to low pressure. In the northern hemisphere Air wind is deflected to the
right of its path by the earth's rotation. moving outward from a "high" flows in a clockwise spiral around

the "high" center; and air moving into a "low" flows in a counterclockwise spiral around the "low"

center.

Flow of air around a high- Flow of air around a high-
and low-pressure area in and low-pressure area in
the northern hemisphere the northern hemisphere

above the surface. at the surface.

Figure 3