Think of air as you would water. Gravity and friction from the air (I think) are the only two forces acting against your golf ball; if the air is moving with your ball instead of against it, the air the ball moves through causes less friction. Water works the same way, if you threw a golf ball into a slide with water flowing 1) toward the ball, 2) neutral, 3) against the ball, you'd fairly obviously get differences in distance.
From what I remember in my physics class, most of fluid dynamics (air and water) just has to do with friction and pressure. Friction would be the direction of the wind (or how the molecules are moving relative to the object), pressure would be the density of the air (how close the molecules are to each other).