The Gradient Force and Coriolis effect are caused by the rotation of Earth. The wind systems influence the weather.   The Gradient Force is the differences between high and low pressure. It's called the pressure gradient force because of the wind. Unequal heating of Earth's surface causes unequal air pressure. The low pressure areas rise. The high pressure areas bring light wind, a steady temperature, and little change in weather. Low pressure areas bring strong winds, dropping temperatures, cloudy skies, and precipitation.