The weather in Samui in January is excellent, making it a generally safe time to visit and be assured of hot and sunny days. The tail-end of the rainy season throws down only 90mm of rainfall, mostly delivered over seven days during the first half of the month. This is usually in short, heavy showers, often in the evenings or at night, leaving the days more often than not dry and cloudless. The average air temperatures are at their lowest at just 26°C/79°F, though the high humidity of between 67% and 92% will make it feel hotter, with only a slight breeze from the southeast to provide some cooling relief. Water temperatures are also around 26°C/79°F and the sea is extremely calm, making great conditions for diving and snorkelling.