Thanks for you help guys,
I suppose I see where you are going Woodman treating a valley as a 2-D hill that's inside out, and if my site is in the bottom half it protects me from wind normal to the valley's length. M2, I think I agree with you that the funneling effects are really the biggest...
In the continuation of Figure 6-4 in ASCE 7-05 or Figure 26.8-1 in 7-10, the chart "Parameters for Speed-Up Over Hills and Escarpments", the first Hill Shape has a note under it that says, "or valleys with negative H..." I cannot find anywhere else in the code that says this factor should be...
