One option is to try to filter out the wind. Most editing programs will allow you to filter out a specific frequency range, and you may be able to get usable dialog by choosing a range that's mostly wind noise. I had the same problem with some documentary footage I was editing a while back and was able to get tolerable sound that way.

Otherwise you'll basically have to play the video back to the actors and record the dialog then try to sync it up to the video. It's a pain, but if you take some care over it no-one will notice: on a short I edited recently they had low sound on the wide shots, but I was able to take the same lines from closeups and replace them by cutting it up into phrases and aligning them carefully with the actors' lips with quick dissolves in between.

I've done a lot of looping (some of it highly unsuccessful) and I have come up with the following system which seems to work fairly well:

- Use the same method of sound acquisition as you did for the actual scene (if you used a shotgun mic on a boom, use the same mic and boom for looping)
- Show the actor the scene a few times to help them remember the pacing. Let them practice it.
- If they can't get the lines right, give them a script to read from. This doesn't seem to impact the performance too drastically.
- When they are ready, have them stand up and act out the motions of the scene while they deliver the lines (makes for more convincing inflections)
- Do not make them try to lip-sync. Do not play back the scene or listen to the old audio while looping (I've found that this leads to very flat, lifeless, poorly-enunciated delivery--and as long as their timing is generally correct you can sync up the recording later without too much difficulty)
- Be sure to get plenty of takes, and don't be afraid to direct their performance and have them try new things with their delivery. This is, after all, half of their performance (and the most important half).
- It's never going to be perfect, but you can get it close. Remember that you're your harshest critic and what seems "pretty good" to you will probably be nearly undetectable to most viewers.

Hope this helps.

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Andrew Gingerich
Exploding Goldfish Films
Check out my vodcast on iTunes: http://phobos.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=96931870
and my blog at http://www.exgfilms.com

thanks a lot!!