I figured it out.
Options > World => under "Weather" choose Turbulence and thermal effects.

Problem solved.

This is really strange. I tried everything, I can't get any turbulance altough I set turbulence in weather settings.

Hello,

In p3dv5, no matter whatever I set on weather setup, I never can get any turbulence or gust. I only get still wind. What could be the reason ?