Wind and waves dictate sometimes where we can dive or where not. In this article, you will get a better understanding of wind and sea states. When I check the forecast I check first the wind speed and after the rain forecast. The safety of the dive vessel and divers on board has the highest priority. Better safe than sorry we use it as a guideline when there is a doubt in the forecast.
Wind and the different seasons in Phuket
The dry season begins in December and usually lasts until March. The northeast monsoon draws cool, dry air from the Asian continent resulting in a slight drop in temperature. This is the high season for tourism in Phuket, when the climate is at its best, characterised by gentle breezes, calm seas and clear blue skies. It is also the coolest time of year.
The transitional periods last a month or so. During these periods the weather is often hard to predict. The period before the rainy season, around April – May, is the hottest time of year. There may be a lot of rain or none at all. The October – November transition is cooler and usually quite wet. These is the months we have to cancel sometimes diving activities due to unfavourable conditions.
The rainy season begins in June and lasts until October. When people talk about the monsoon season, they are referring to the southwest monsoon period, which is the rainy season. The weather pattern is quite predictable with 3 days of heavy rain and strong wind followed by many sunny days with calm sea. The strong winds bring warm moist air from the Indian Ocean and plenty of rain. This is Phuket’s low season.
How is the wind affecting scuba diving?
With west or east wind, the boat is rolling when travelling to Racha Islands and pitching when travelling to all other dive sites. When the boat pitches passengers will feel more comfortable during the ride.
Two wind directions and two main seasons
In the dry season with wind from the east, waves can’t build up that high as the mainland is not that far away. The Sea state is mostly between calm and slight, rarely moderate and more. In the rainy season when the wind is blowing from the west and southwest waves can build up quite high as the African continent is far. Therefore wind has time to build waves. What makes surfers happy at the west coast beaches (Karon, Kata, Patong) is for scuba diving in Phuket a limiting factor. Unpredictable thundershowers in the rainy season are the biggest thread for boats. Sea state there can be rough. We operate up to moderate sea state. Forecasts are not that accurate in the tropics. Therefore the final decision on which dive site will be dived can only be taken on short notice, sometimes in the morning of the trip. But when we are in doubt we cancel a dive trip free of charge for your comfort and safety.
Why is the sea sometimes “choppy”?
Wind with tide – smoother water
Wind against the tide rougher water