UV Index
UV Index
Today's UV index in Ko Lanta Yai, Thailand 
will be up to 12.5, indicating a extreme level of sun exposure for the average person. Check our tips for today to make sure you're safe in the sun.
Last checked: 2025-05-10
UV index at 12.5 in Ko Lanta Yai means extreme risk: limit outdoor time especially from 10 a.m. to 4 p.m., actively seek shade, wear protective clothing, broad-brimmed hat, apply SPF 30+ sunscreen every 2 hours, and wear UV-blocking sunglasses. Watch for bright surfaces like water and snow increasing UV exposure.
The UV index in Ko Lanta Yai is often high, especially between March and May, reaching levels around 10 or more. During other months, it ranges from moderate to high, around 5 to 9.
Ko Lanta Yai has a tropical climate with three main seasons: a hot season from March to May, a rainy monsoon season from June to October, and a cooler dry season from November to February. Rainfall is heaviest during the monsoon months.
Compared to mainland Thailand, Ko Lanta Yai is slightly cooler during the dry season due to sea breezes. It generally has less extreme temperatures than northern Thailand. Neighboring countries like Malaysia share similar tropical conditions, but Ko Lanta Yai is less rainy than some Malaysian west coast areas.
See the UV index hour by hour for Ko Lanta Yai, along with the temperature and how cloudy it is. If the UV level is higher than moderate, it's best to avoid direct sunlight.