a) The wind is generated because there are different values of pressure in the amtophera. That is, it is generated due to a pressure difference between two atmospheric points. Generally the movement is performed when the air travels from the highest pressure point, to the lowest pressure point. This is also a direct cause of different types of wind speeds.
b) If the cloud moves from one direction to another, it will indicate that from the starting point the pressure is higher, and the point towards which it is directed, the pressure is lower. If we place this on a Cartesian plane with reference to the cardinal points, we can know the approximate place or area where the pressures are different.
