You should stay with a pack rather than be stuck on a goal pace, even if it is little faster than you might want to go. I am sure with the wind a nice big pack will form.
At Chicago this year (10 mph SSE wind) a huge pack formed of around 40 people going 6:00 minute pace. Pack started forming right in front of me going north bound with the tail wind. I didn't try to catch them because they were going a bit faster than I wanted to go- I just wanted to sneak under 2:40. When we started going southbound the wind was horrible. I decided to surge to catch them and I could not believe how much easier it was once I caught them. I hung with them until mile 21- much under 2:40 predicted at that point. Despite losing them, I still managed well under 2:40.
At 2013 Chicago, there was not much wind until the final 3 miles so no such pack formed, at least not around me. I really think the windier conditions this year helped me go quite under my goal time by causing a pack to naturally form.
The 20 mph mostly headwind you all will face will surely suck far worse than the 10 mph at Chicago, but hopefully a pack will stay strong- just do everything you can not to lose them.
My longwinded point is, do not let a pack get away from you, even if a little faster than you want to go. The effort maintaining your pace alone will be far greater that keeping up with the pack at a slightly faster pace.