Seasons are critical for anyone coming to Phuket to follow a specific activity or sport, for weather conditions control exactly what you can and cannot do. There are only two basic seasons, the dry season and the monsoon season. The normal dry months stretch from November till May, while the monsoon usually lasts from May or June through October. September and October are usually the wettest months of the year, though even during this period the rains are usually broken by off-and-on spells of fine weather.

The dry months are ideal for virtually all beach activities and watersports, including diving, swimming, sea canoeing, boating, and fishing. At this time of year the waters throughout the Andaman sea are especially calm. The beaches on Phuket’s West coast are at their finest, with the water clear and warm, averaging about 28 degrees Celsius.
Some mountain biking and trekking is organised by tour companies on Phuket, and this can usually be done all year round.

Sports that depend on the wind – sailing & windsurfing – are best from November through February when the Northeast winds blow steadily, but bring little rain. It is during this time – December – that the annual Phuket King’s Cup Regatta is held.

Sea canoeing and game fishing are also good during the monsoon season. The best sea canoeing is to be had among the scores of islands in the bay of Phang Nga which is well-sheltered from the monsoon winds. Fishing is good during the wetter months since it is then that sailfish gather around neighbouring islands in huge schools and put on dramatic displays of jumping and splashing.
There is limited white-water canoeing in streams north of Phuket, and these run only during the wet months.