For Koh Tao :
No gale warning.
The reliability of the situation is good.
Very cloudy with risk of thunderstorms in the morning, skies clearing but storms likely in the afternoon. Showers all day. In the evening, changeable skies with risk of storms.
Light showers progressively becoming less frequent. S force 3 becoming SSE force 4 in the middle of the day then S. Smooth to slight sea. Low, short swell from SSE. Excellent visibility becoming good in the evening.