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The horizontal pressure gradient force is the driving force for the wind. The other two forces, friction and coriolis, only come into play when the wind begins to blow. They make it possible for winds to be sustained at nearly steady speeds for long periods of time.
Air parcels tend to attempt to come into equilibrium, with all the forces approximately balancing and little or no acceleration. For rapidly-changing pressure gradients, an equilibrium may never be reached. Near the ground, friction is important and frequently balances the pressure gradient force, leading to sustained winds blowing from high to low pressure.
When the pressure gradients are felt for long periods, particularly for large-scale weather systems, a balance is achieved between the pressure gradient force and the coriolis force, called geostrophic balance. The large-scale wind tends to blow parallel to pressure or height contours, with low pressure to the left and high pressure to the right. In this configuration, the pressure gradient is directed from right to left and cancels the coriolis force, which is directed from left to right. Meteorologists commonly use maps of pressure or height to infer the large-scale wind pattern.
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