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Sooooo, I'm guessing due to the Coriolis effect that weather systems in the Southern hemisphere circle "the other way". i.e. H's move counterclockwise and L's clockwise? Do Hurricanes (Himacanes?) rotate clockwise? Tornados? I guess tornados can form either way, but which is "preferred"? How 'bout near the equator? No rotation at all?? No hurricanes possible? Nothing to fuel the rotation? Wassup with ol' Grandpappy Coriolis? -Mike G. p.s. and while I got you spinnin', how 'bout those little "tornados" that form in the bathtub? Other way?
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Here's the deal, the weather in the Southern Hemisphere moves the opposite way. It has to do with the Coriolis Force and also the Pressure Gradient Force.
Air flows from high to low pressure but the earth is rotating all the time. This means that air actually doesn't follow a straight path but the path is curved. In the Northern Hemisphere this path deflects to the right, in the Southern Hemisphere to the left. This is called the Coriolis force. The pressure gradient force (PGF) also plays a role in our weather systems, it pushes air to the center of an area low pressure. This force is caused by pressure differences.
The Coriolis force only affects large scale winds which means....the toilet DOES NOT flush the other way in the Southern Hemisphere even though people will argue with you that it does.
Low pressure where we live in the North moves counterclockwise and highs move clockwise. In the South the opposite is true. Low pressure moves clockwise and high pressure moves counterclockwise. Weird huh? Yeah, try forecasting it! Since a hurricane is an area of low pressure, it will move clockwise in the Southern Hemisphere. Tornadoes will also move clockwise in the Southern Hemisphere. Rarely, a tornado can move clockwise in the Northern Hemisphere but not very often.
Near the equator, the Coriolis Force is zero. Winds will be delfected more near the poles than the equator. Hurricanes usually do not form within about 5 degrees of the equator. Some argue that the force is too weark there to deflect the winds around a forming area of low pressure.
