October to March is the strongest default season
For most travelers, October to March is the easiest season to recommend. Weather is more comfortable, road travel is smoother, and sightseeing days are easier to plan across Munnar, Alleppey, Thekkady, and Kochi.
This is also the most reliable period for family packages, honeymoon travel, and first-time Kerala itineraries where comfort matters as much as scenery.