The weather in Samui in July is generally very good. Temperatures are still high, at an average of 29°C/83°F, while humidity is at a comfortable average of between 61% and 89%. You are likely to get a few more cloudy days, with some afternoon rain showers on about nine days dropping the 120mm average rainfall. They are usually gentle and short-lived, making them nothing much to worry about. Sea conditions are also good, with the water temperature around 28°C/82°F and westerly winds providing good sailing and surfing on the west coast while the sheltered east coast still enjoys good swimming, snorkelling and diving opportunities.