Wind is difficult because it contains a lot of frequencies but you can get the rumble part out right in Vegas with fairly good results. Go into the track FX and select the Track EQ that is already added for you. The first point is already set for Low Shelf, which is what you want to get the rumble out. Set the Frequency (Hz) to 300 and the Gain (dB) to –Inf (all the way to the left). Now listen to a loop of your audio and adjust the frequency to filter more or less of the wind.
The trade-off is that other audio will sound a little thin because you’ve removed some bass. If you add some music softly playing in the background on another track, it will mask this because the music will have full fidelity and provide bottom to the mix. If adding music is inappropriate for your video then you have to live with the thin sound or pay a lot more for iZotope RX, Sony Noise Reduction 2.0, or Sound Soap 2.
If you have the budget, iZotope RX is the best noise reduction tool out there for the price. I believe you can download a trial so see how it works for you.
~jr
http://www.johnrofrano.com
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