Travel time: Year-round
Located in the Idukki district of Kerala at an elevation of approximately 700 to 1,900 meters above sea level, Thekkady (Kumily) experiences a tropical mountain climate. Unlike the sweltering plains of southern India, Thekkady remains relatively temperate throughout the year. The weather is defined by three distinct phases: the cool, dry winter; the warm, sunlit summer; and the powerful, rejuvenating monsoon.
Thekkady’s weather follows a predictable daily cycle that creates a distinct sensory experience. In the early morning hours, particularly between 4:00 AM and 7:00 AM, the region is often draped in a thick, cool mist that clings to the spice plantations and the surface of Periyar Lake. As the sun rises, the mist clears, leading to bright, crisp mornings.
The heat peaks around 3:00 PM, but even on the warmest days, the air rarely feels "oppressive" due to the elevation and the constant breeze filtering through the dense evergreen forests. Evenings bring a sharp drop in temperature; there is a tangible "cool-down" as soon as the sun sets, often requiring light layers even during the summer months.
This is the peak season for a reason. The temperatures typically range from 15°C to 27°C. The air is dry, and the sky is a deep blue. This period transition from the "Thulavarsham" (retreating monsoon) into a stable, cool climate. It is the time of year when the landscape is at its most comfortable for trekking and outdoor activities.
Temperatures climb to a maximum of 33°C to 36°C. While the days are warm, the vegetation remains lush compared to the rest of India. This season is vital for wildlife enthusiasts: as the smaller forest water holes dry up, animals such as elephants and Malabar giant squirrels migrate toward the permanent waters of Periyar Lake, significantly increasing sighting probabilities.
Thekkady receives approximately 2,386 mm of annual rainfall, with the bulk arriving during the Southwest Monsoon. June and July are the wettest months. The weather during this time is a dramatic display of nature’s power; heavy downpours are punctuated by periods of haunting stillness. The forest turns a vibrant, neon green, and waterfalls like those in Chellarkovil become spectacular.
Thekkady serves as a gateway between the humid Kerala coast and the rain-shadow regions of Tamil Nadu. Just 40 kilometers away at Ramakkalmedu, the geography creates a unique wind tunnel effect, making it one of the windiest places in Asia. Within the Periyar Tiger Reserve itself, the microclimate can vary; the dense evergreen core remains cooler and more humid than the open grasslands and deciduous areas near the park's periphery.
Historically, the cool climate of Thekkady made it a favored hunting ground for the Maharajas of Travancore and later a prime location for British tea and spice planters. The construction of the Mullaperiyar Dam in the late 19th century permanently altered the local climate by creating a massive artificial reservoir, which helps moderate local temperatures through evaporation.
Locals have adapted to this humidity and rain by building a world-renowned spice industry. The specific combination of high rainfall and cool mountain air is what allows cardamom, black pepper, and cinnamon—often called "black gold"—to thrive here. During the heavy monsoon, local life slows down, and residents focus on the internal maintenance of plantations, knowing that the heavy rains are essential for the next year’s spice harvest. For a traveler, the weather "feels" like a constant interaction with the forest; you are never far from the scent of damp earth or the cooling influence of the dense canopy.