An weather forecast instrument (wind vane), for measuring the direction of wind, from north, south, east or west and also the speed. Sound included. The design of a wind vane is such that the center of gravity is directly over the pivotal axis, so that the pointer can move freely on its axis, but the surface area is unequally divided. The side with the larger surface area is blown AWAY from the wind direction, so that the smaller side, with the pointer, is pivoted to face INTO the wind direction. For example, in a ‘Nor-Easter’ (a wind that blows FROM the north-east), the pointer will point TOWARD the north-east. Most wind vanes have directional markers beneath the arrow, aligned with the geographic directions.