The flying season runs from September to May. In July And August all your flying hopes will be washed away by the monsoon. The best months are from October to November and from March to April when the 'real' thermals are kicking in. The months December, January and Februari are generally flyable, but due to a low inversion layer it is hard to actually find thermals that will bring you sky high. And a pair of warm gloves is highly recommended!