The best time to visit Thrissur, Kerala, is during the winter months from October to February when the weather is pleasant, making it ideal for exploring the city's attractions and enjoying outdoor activities. The monsoon season from June to September brings heavy rainfall, enhancing the region's natural beauty but may limit outdoor activities. Summers from March to May are hot and humid, making indoor attractions more appealing, though it's the off-season with fewer crowds and better deals on accommodations. Overall, Thrissur offers something for every traveler throughout the year.