I was playing my beautiful sounding bluebird D whistle on a pleasant summer day. Everything was so nice. Suddenly my whistle was not sounding right. I figured some moisture was the culprit, but it was not the case. Dry as a bone. I played again and it was good as new.
Suddenly my lower notes where going all crazy like.
I was going nuts 
Then I noticed that when the wind blew, it messed with my whistle. 
Being a piper I have never had to think about the wind too much. If it is really windy it can shut off a drone maybe, but it was just a little windy.
I guess this is this normal? 
Are there any tricks to playing in the wind other than turning my back?
Oh yes yes yes. Very normal.
http://www.youtube.com/watch?v=ixckTW21e4I
You can also try turning the whistle head around 180 degrees so that the fipple window faces your chest, and hold it as close to you as you can manage.
A paper or plastic cup with a hole in the bottom and cut to size could be mounted as a fipple shield.
But sometimes the solution is to give up. 
A friend of mine played an entire concert set with his back to the audience because of the headwind blowing onto the stage. The audience thought he was just very shy.
Also keep in mind that different whistles may have different wind resistance. You can check this by playing directly into a table fan at home, and choosing your most wind-friendly whistle.
Is whistling trad music in the wind what they mean by Gael force? 
Tricks!!!??? I can hardly believe that MTGuru did not mention the Tidy Cat set. 
http://www.youtube.com/watch?v=ixckTW21e4I
Yes, even the pros have to deal with the wind.
Feadoggie
Oh, but I did, I did! Look closely. I aim to please …
Thank you for your wisdom!
Now if I can only bring a fan to the session to quiet the noodler who fakes every tune. 
Now we know the real reason for the those baskets.
One: get a Copeland. He puts a little three-sided “box” around the opening of the fipple for just that reason. But see the sticky thread on how easy it is to get one.
isn’t there a song by that name, “Blowing In The Wind”? I think just about everybody sang it, wind, no wind…
Years ago I played a wedding and was supposed to march the wedding party about a block to the reception. They wanted whistle not pipes, and the reception hall was dead upwind from the ceremony. Wish I had known the turn the fipple trick. I marched the whole block backwards with the guitar player leading me by my
coat tail.
JD
Gosh yes. I often practice outside, and forget facing into the wind.
Needs video! 