In an earlier answer there was a point raised about direction of shear (abetting/retarding) cylone formation. It appears westerly shear hinders the formation of tropical cylones and easterly shear enhances it. This should mean that cyclone formation is only allowed over monsoonal regions. Is that accurate ? From this article - http://www.cwb.gov.tw/V7/climate/climate_info/information/lectures/14/Lecture_1_Wave_and_Response.pdf it appears that in the presence of westerly shear Rossby waves have large amplitude at the upper troposphere whereas easterly shear has large amplitude in the lower troposphere. Given that the precursors of tropical cyclones are equatorial waves can a clarification be provided in this regard ? 

Moderators can decide whether additional tags are required such as tropical cyclone, equatorial waves, wind shear.