The angle of the crosswind can also determine the deviation of a bullet's path. Perpendicular winds—90 degrees to a bullet's path—will have the greatest effect, with smaller angles having less of an effect. Winds blowing parallel to a bullet's trajectory path will have such a small effect on the bullet that the wind drift can often be ignored.
To find the exact effects of wind drift in question, we recommend reading this article: "Expert Forum: Wind Shooting"