Thailand Rainy Season - Weather Information

Seasonal Coastal Conditions in Thailand

Coastal conditions vary in somewhat of a predictable pattern. This information may be especially useful for persons taking surface craft to island destinations. Scuba divers will also be interested.

During months when large waves are predicted, you may be more comfortable flying.

Andaman Sea - Expected Weather Conditions
Months	Underwater	Surface
Jan-Mar	Excellent	Calm
Apr	Good/Excellent	Calm/choppy
May-Oct	Poor/Good	Choppy/rough
Nov-Dec	Good	Choppy
Comment: recent years have seen east winds strengthen and may prevent smaller boats from reaching distant sites
Koh Phi Phi - Expected Weather Conditions
Months	Underwater	Surface
Jan-Apr	Excellent	Calm
May-Jul	Good	Choppy
Aug	Fair	Choppy
Sep	Fair	Choppy
Oct	Fair	Choppy
Nov-Dec	Excellent	Calm
Comment: Protected because of location
Koh Lanta Area - Expected Weather Conditions
Months	Underwater	Surface
Jan-Apr	Excellent	Calm
May-Jun	Fair	Choppy
Jul-Aug	Fair/Poor	Choppy/Large waves
Sep-Oct	Poor	Large Waves
Nov	Good	Choppy
Dec	Excellent	Calm
Butang Group/Koh Tarutao - Expected Weather Conditions
Months	Underwater	Surface
Jan-Feb	Good	Choppy
Mar	Fair	Choppy
Apr	Fair	Calm
May	Good	Calm
Jun-Aug	Excellent	Choppy
Sep-Oct	Excellent	Large waves
Nov-Dec	Excellent	Choppy
Comment: winds from the west - clean clear water from the Indian Ocean depths
West Gulf of Thailand - Expected Weather Conditions
Months	Underwater	Surface
Jan-Feb	Fair/Good	Choppy
Mar	Excellent	Calm
Apr-Jun	Fair/Good	Choppy
Jul-Aug	Excellent	Choppy
Sep	Excellent	Choppy
Oct	Excellent	Calm
Nov-Dec	Poor	Large Waves
Pattaya - Expected Weather Conditions
Months	Underwater	Surface
Jan-Mar	Excellent	Calm
April	Fair	Large Waves
May	Fair	Rain, large waves
June-Aug	Good	Choppy, SW
Sep	Excellent	Some rain, flat seas
Oct	Poor	Rain, storms
Nov-Dec	Good	Choppy, NE
Note: SW=Southwest Monsoon   NE=Northeast Monsoon
Koh Chang - Expected Weather Conditions
Months	Underwater	Surface
Jan-Mar	Excellent	Calm
April	Fair	Large Waves
May-Oct	Poor	Rain, large waves, SW
Nov-Dec	Good	Choppy, NE
Note: SW=Southwest Monsoon   NE=Northeast Monsoon

Thailand Weather