UV Index
UV Index
Today's UV index in Chiang Mai, Thailand 
will be up to 12.7, 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: 2025-06-01
UV index at 12.7 in Chiang Mai 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.
Chiang Mai's UV index varies seasonally, reaching very high levels around 10 to 12 during the hot months from March to May. It is lower during the rainy season and coolest months, typically between 4 and 7.
The city experiences three main seasons: a hot season from March to May, a rainy season from June to October, and a cool season from November to February. Temperatures peak in April and drop to their lowest in December and January.
Compared to other parts of Thailand, Chiang Mai is cooler during the winter months due to its northern location and higher elevation. Neighboring countries like Myanmar and Laos have similar seasonal patterns but generally experience higher humidity and more intense monsoon rains.
See the UV index hour by hour for Chiang Mai, along with the temperature and how cloudy it is. If the UV level is higher than moderate, it's best to avoid direct sunlight.