What controls horizontal wind direction and speed?

The dynamics of horizontal wind direction and speed are primarily influenced by the pressure gradient force, Coriolis force, and friction force. The pressure gradient force arises from the difference in atmospheric pressure over a distance; it pushes air from areas of high pressure to low pressure, initiating wind.

The Coriolis force modifies the direction of the wind due to the Earth's rotation, causing winds to curve rather than move directly from high to low pressure areas. This effect is more pronounced at larger scales and is a critical factor in determining wind patterns globally. Additionally, friction force comes into play when winds move over the Earth's surface, slowing down the wind and altering its direction, particularly at lower altitudes where surface roughness, such as trees and buildings, affects airflow.

In contrast, while temperature and humidity can influence local wind patterns by affecting pressure systems, they do not directly control wind direction and speed in the way the forces mentioned do. Similarly, altitude and pressure are essential in understanding atmospheric conditions but are not the primary factors for horizontal wind dynamics. Geographical location may influence local weather patterns and temperature, but it does not dictate wind direction and speed as effectively as the governing forces do.