You only need to worry about wind if you don't know how to use it ; )
I wanted to see how the air would handle flying into head on winds and got a pleasant surprise on the return flight home. Wind speeds yesterday were averaging around 10-15mph with gusts up to about 22mph during my flight. At the beginning of the video I was flying into the wind in sports mode with the right stick pushed completely forward. Despite this, the air was still able to maintain a respectable 35-40 KPH and was very stable. (and the video feed was perfect too!) I was getting nervous getting close to 50% battery so I decided to turn around, but obviously I should have gone further because my Air was back in sight in no time!
Normally we don't have too much wind around my flying area but yesterday it was particularily different and having a look at my files it went downhill at 75,9Km/h. Wow... that was fast.