The weather in Koh Lanta
If the forecast on the right is showing rain, don't despair! The weather in Krabi changes frequently: if you click on the 'forecast' button, you will see the real time weather - often different from the day's original prediction shown here.
Koh Lanta is in a tropical climate zone, only 8 degrees above the equator. There are two seasons here: hot and dry; and 'cool' and wet - although the temperature rarely drops below 27C year round. These weather seasons roughly correspond with the tourist high season (from November to April) and low season (from May to October) - most people prefering to visit during the hotter, drier months.
But, unfortunately, the monsoon winds that control Lanta's weather do not switch direction on time every year, which means that the rain (like in 2007) can start late in June, stop for a couple of months and continue well into January.
So there can be rain during the 'dry' season, particularly at the start, as well gloriously sunny spells for sometimes weeks at a time during the 'rainy' season. The only weather that can be almost guaranteed during the year is a dry heatwave in March and April (up to 37C) and prolonged rainy spells in September and October. The best time to visit is January or February where clear blue skies can nearly always be counted on but it is still relatively cool.
Yearly temperatures in Ko Lanta average around 28-32C during the day, with a maximum of around 36C during March and April and a minimum of 20C - a temporary drop during a big rainstorm. During the night, the temperature drops around 5-10C and you may feel chilly if you have been out in the sun all day - you should pack a light, non-woolly sweater or shawl for the evenings.
Humidity levels are high throughout the year, from 75% to 100% - if you are sensitive to humidity, avoid going on any jungle treks or visits to National Parks where the greenery makes things worse.
The sea temperature is a very pleasant 28-30C all year round.