Wind is a direct effect of air trying to get from high pressure to low pressure. Because there is such high pressure, it is natural for air (or anything for that matter) to move into an area of lower pressure. Water does it. If it is in a cup and then a straw is connected to the side of the cup and attached to another, the water goes because there is space for it; less pressure.

However, because the Earth is spinning, that flowing air can't just go from high to low pressure. It flows to the right in the Northern Hemisphere and flows to the left in the Southern Hemisphere. However, because of the spinning of the Earth, the air flow actually goes around the high and low pressure. This is what occurs in a long pressure system. In a short pressure system (such as a storm leaving), the wind just flows from high to low.

When these two pressures (high and low) begin to get closer together, the winds begin to get stronger. Because they are closer, the flowing air wants to get to the other pressure faster and therefore, it moves harder which results in more powerful winds.

The ground of the Earth is known for slowing winds down due to friction. If there was no friction, winds would be able to flow freely; however, at night, that isn't the case. During the day, the Earth's effect on wind is minimized due to convective mixing; however, at night, when there is no convective mixing, the winds can stop almost entirely.

Finally, it is suggested that wind is the atmosphere's method of getting heat around the Earth. Because wind can carry heat energy, as the wind blows, it can move heat from places that have it to places that don't.

In the end, though, the higher the initial pressure and the lower the final pressure plus the closer these two pressures are, the stronger the gusts of wind. In 1934, there were gusts up to 231 mph on top of Mt. Washington in New Hampshire due to an incredibly strong jet stream that was suddenly came very low.