There are two distinct seasons in the area, these are the North East Monsoon and the South West Monsoon seasons. Below is a rough outline of what you can expect in each season.

North East Monsoon Season

The North East Monsoon Season starts from the beginning of November and stops around the end of April. This season carries winds from the North East and is generally the calmer season with moderate winds and seas that are often without swells or if there is a swell it is usually no more than 0,5 metre high in Phang Nga Bay with swells of around 1 metre near Phi Phi Islands. These swells usually have a long wave period. This is definetely the most comfortable time to go sailing in Thailand.

South West Monsoon Season

The South West Monsoon Season starts from the beginning of May and continues until the end of October. The South West Season carries winds from the South West and generally you will find that this is more of a serious sailing season, with winds that are stronger than in the North East Season, one might encounter occasional squalls that last for about 10 to 30 minutes. Foul weather gear is usually necessary during this season, even though, one can often encounter good weather for the duration of the cruise. The swell is naturally more rough with, swells of up to 1,0 metres in Phang Nga Bay and up to 3 metres towards the South of The Phi Phi Islands.