How to make the wind blow with randomized patterns? Like for storms and calm breezes?
Your question is quite broad, but I think I can point you in the right direction. You have two approaches each with its pros and cons.
1.) Simulate real physics
Pros: the most close to reality.
Cons: computationally expensive, hard to program.
2.) Use noise
Pros: faster to implement and runs fast also.
Cons: not so close to reality
If you go with the first one you have to implement 3/2 dimensional Computational Fluid Dynamics CFD, I would go with a shader approach. GPU Gems is an excellent source. If you go for the second option I recommend Curl Noise for nice swirly patterns. I think that you better implement either of the approaches on the GPU for performance.