Pressure changes a. more rapidly in the horizontal direction than in the vertical. On an upper-level chart the wind tends to blow a. at right angles to the isobars or contour lines. The force that would cause a stationary parcel of air to begin to move horizontally is called the a. Coriolis force. The net force acting on air which is blowing parallel to straight contours at constant speed is a. in the direction of wind motion. Suppose that the winds aloft over Tucson are geostrophic and blowing from the north.
Low pressure is located to the a. north.