Phuket is in the south of Thailand and close to the Equator that made Phuket had three seasons is the cool season, the hot season, and the rainy season. The climate is affected by the monsoon winds, which are the direction of the prevailing winds caused by the difference in the way oceans and land heat.
The great land mass of Asia is warmer than the Indian Ocean from May to November. The colder, heavier air over the Indian Ocean pushes into the warm air over the continental land mass. This causes the prevailing winds to come from the southwest over the Indian Ocean, bringing lots of warm moist air and therefore lots of rain.
Then as the Asian continent cools from November to April, the ocean becomes warmer than the land. The prevailing wind direction changes to come from the northeast. That is from the great land mass of China bringing cooler, drier air and good weather. The result is a fairly predictable weather pattern.
The Cool Season
From November to February the weather is cool season. The northeast winds normally start sometime in November bringing an end to the rainy season. The cool season is the best time of year to visit Phuket. There is lots of blue sky, very little rainfall, lower humidity and the temperatures are comfortably hot. This is Phuket's high-season with the peak of visitors coming over the Christmas and New Year period.
The Hot Season
The hot season is from March to early May. The weather is dry and the skies blue but many people find the temperature is a little too hot for comfort. This is mid-season for Phuket. There are still a lot of visitors but the hotels start to lower their rates around this period as demand drops.
The Rainy Season
The monsoon winds from the southwest start in early May and bring the rain. The highest rainfall comes in May, September and October. In these months it can rain for long periods. These three months are definitely not the time of year to come if you want sun or outdoor activities. However, June, July and August are good months to visit. During these three months, there will be plenty of rain but it usually falls in short heavy bursts. In between, the weather is pleasant with comfortable temperatures and a cooling breeze. There will often be periods of several days without any rain.
Blue sky, little rainfall, It will be beautiful and temperatures are comfortably hot.
The temperatures are starting to rise but sill in the comfortably hot range.
It will be beautiful but the temperature starts to get a little too hot for comfort. There is lots of blue sky and very little rainfall.
That is too high temperatures can reach a level for most people's liking. At some point towards the end of this month the rainy season arrives.
This is the second wettest month of the year. It will rain often and sometimes for long periods. On the plus side, the rainy season well and truly arrives. the temperature drops back to levels that are more comfortable.
Temperatures are comfortable with a cooling breeze. The rainy season is here but it settles down to a less annoying level. It will rain often but usually they are only short downpours. There are often several days without rain and there is a little blue sky in the breaks.
The downpours are an inconvenience but not a major annoyance. The rainy season continues. Temperatures are comfortable with a cooling breeze. There may be several days without rain and there is a little blue sky in the breaks.
The school holidays in Europe mean a lot of people choose this month to visit and take advantage of the low-season prices. This is almost a mini high-season month. There are also a lot of Australian visitors this month. There may be several days without rain and some blue sky in the breaks. Temperatures are comfortable with a cooling breeze. The rainy season continues but the downpours are an inconvenience rather than a major annoyance.
It will rain often and sometimes for long periods. There will be very little blue sky. This is the wettest month of the year. This is also the coolest month of the year although average high temperatures are still close to 30 degrees centigrade.
This is the third wettest month of the year. There will be very little blue sky. The rainy season continues to soak Phuket. It will rain often and sometimes for long periods.
Temperatures start to pick up towards the comfortably hot high season level. At some point in this month the rains will stop. This is the official start of the high season. There will still be showers and the occasional heavy downpour but the main rains have finished. The sky will be a mixture of cloud and blue.
The high season and the crowds are well and truly here. There will be an occasional shower and perhaps even a few heavy downpours but generally, it is dry. The sky is mostly blue but there is still plenty of passing white cloud. The temperatures are now reaching the thirties.