What causes the winds to blow as they do around high- and low-pressure areas?
Winds near the Earth s surface rotate counterclockwise toward the center of areas of low pressure and clockwise outward from the center of areas of high pressure in the Northern Hemisphere, with an opposite flow (clockwise around areas of low pressure and counterclockwise around areas of high pressure) occurring in the Southern Hemisphere. The main reason for this pattern is the Coriolis force, which results from the Earth s rotation on its axis and deflects wind to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Without the Coriolis force, air in the Northern Hemisphere would flow directly toward the center of areas of low pressure from all directions and directly out from areas of high pressure, with the opposite occurring in the Southern Hemisphere. For more, see this USA TODAY resource page on understanding the Coriolis force.
