2005 Explorer wind noise high speeds
 

I cannot pinpoint the source of a terrible high pitched wind noise in my 2005 E. B. Explorer V8. At 70 m.p.h. a constant wwind whistle comes somewhere from the front driver side. The wind must be blowing in a cross wise direction to cause it so it is not always there. However when it whistles it is extremely annoying. Has anyone else had this problem and found a solution?