Thiruvananthapuram has a tropical climate with two monsoon seasons. The southwest monsoon runs from June to September and is the main wet season — heavy daily rain is the norm, humidity is intense, and outdoor sightseeing becomes uncomfortable. The northeast monsoon brings lighter rains in October and November.
The best time to visit is November through February, when temperatures are around 25–28°C, humidity is lower, and the skies are mostly clear. March and April are the hottest months before the first monsoon breaks, with temperatures reaching 35°C or more. The annual Nishagandhi Dance and Music Festival typically runs in late January, and the Onam harvest festival in August–September is spectacular despite the rain.