The best time to visit Thailand, without a doubt, is from November to April. It's Thailand's dry season, characterized by sunny days and minimal rainfall. The weather is pleasant during this period, with temperatures ranging from 28 to 34 degrees Celsius, making it ideal for sightseeing, outdoor activities, and also for a beach vacation in the beautiful southern beach resorts such as Phuket, Koh Phi Phi, Krabi, and more.