Chiang Mai experiences a tropical climate with three distinct seasons: a cool, dry winter; a hot, dry summer; and a lush, rainy monsoon. Winters are mild and sunny, summers can be intensely hot, and the rainy season brings vibrant greenery and frequent showers. Each season offers unique experiences for travellers, from festivals to outdoor adventures.
The best times to travel section shows how the months compare for a visit, so you can find the time of year that fits what you want to do.
Background colours of the months:
The colour shows the typical temperature: yellow (hot), green (mild) and blue (cold). How strong the colour is shows the travel season: full colour means high season, soft colour means shoulder season and soft-striped means off season.
Weather symbols:
Each month has one symbol showing what the weather is typically like, such as hot and sunny, freezing or a rainy or snowy season. Use them to quickly spot months that match the weather you want, or to avoid the ones that don't.
Crowdedness:
The people icon shows how busy the place usually is. The more people, the more crowded it gets.
Additional notes:
The grey info boxes point out special things worth knowing, like recurring weather issues or seasonal events.
Chiang Mai’s climate is defined by its mountainous location in northern Thailand, resulting in three main seasons: cool (November–February), hot (March–May), and rainy (June–October). The cool season is the most popular, with daytime highs of 25–28°C and nighttime lows dropping to 13–16°C. Skies are clear, humidity is low, and rainfall is minimal, making this period ideal for outdoor activities and festivals like Loy Krathong and Yi Peng. Evenings can feel crisp, so a light jumper is recommended.
The hot season, from March to May, sees temperatures soar to 36–40°C, with April typically the hottest month. Humidity rises, and nights remain warm, offering little relief from the heat. This period is perfect for water-based activities and the lively Songkran (Thai New Year) festival. The landscape can appear dry and dusty, and air quality may be affected by agricultural burning in March and April.
The rainy season (June–October) is marked by frequent, heavy showers, especially in August and September, when monthly rainfall can exceed 200 mm. Daytime temperatures cool slightly to 29–33°C, but humidity and nighttime warmth increase. The countryside becomes lush and green, waterfalls are at their best, and crowds thin out. Sunshine is less abundant, but there are still breaks for exploration. Winds are generally light, and tropical cyclones are rare, though remnants can bring extra rain. Snow does not occur in Chiang Mai.
| Average climate data for Chiang Mai, Thailand | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Average maximum temperature (°C) | 30 | 33 | 35 | 37 | 34 | 33 | 32 | 31 | 32 | 31 | 30 | 29 | 37 |
| Average minimum temperature (°C) | 15 | 16 | 20 | 23 | 24 | 24 | 24 | 24 | 23 | 22 | 19 | 16 | 15 |
| Average precipitation (mm) | 4 | 9 | 18 | 58 | 163 | 123 | 139 | 215 | 214 | 119 | 53 | 16 | 1,132 |
| Average rainfall days (days) | 1 | 2 | 2 | 6 | 14 | 14 | 16 | 18 | 20 | 14 | 5 | 1 | 113 |
| Average relative humidity (%) | 67 | 58 | 52 | 58 | 70 | 77 | 79 | 81 | 82 | 79 | 74 | 73 | 71 |
| Average daily daylight hours (h) | 11 | 11 | 12 | 12 | 13 | 13 | 13 | 12 | 12 | 11 | 11 | 11 | 12 |
| Average daily sunshine hours (h) | 8 | 9 | 8 | 8 | 7 | 5 | 5 | 5 | 5 | 6 | 7 | 8 | 7 |
| Average UV index | 9 | 11 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 11 | 9 | 8 | 11 |
The best time to visit Chiang Mai is from November to February, during the cool season. Temperatures are comfortable, humidity is low, and skies are clear, making it perfect for outdoor adventures, cultural festivals, and exploring the city’s temples and natural surroundings. This period is also the busiest, so book accommodation in advance.
The least favourable time to visit is late March to April, when extreme heat (often over 38°C) combines with poor air quality from agricultural burning, reducing visibility and comfort. The rainy season (August–September) can also be challenging due to frequent, heavy downpours, though the landscape is lush and crowds are smaller.
Chiang Mai has three main seasons: a cool, dry season from November to February; a hot, dry season from March to May; and a rainy monsoon season from June to October. Each offers different travel experiences.
The best weather is from November to February, when temperatures are mild (15–28°C), humidity is low, and skies are clear. This period is ideal for outdoor activities, sightseeing, and enjoying local festivals.
During the hot season (March–May), daytime temperatures often reach 36–40°C, with April being the hottest month. Nights remain warm, and humidity can make the heat feel even more intense.
The rainy season lasts from June to October, with August and September being the wettest months. Heavy showers are frequent, but they usually pass quickly, leaving time for exploration between downpours.
Humidity is highest during the rainy season and hot season, sometimes exceeding 80%. The cool season is much less humid, making it the most comfortable time for outdoor activities.
Yes, air quality can be poor in March and April due to agricultural burning and forest fires. This haze can reduce visibility and affect those sensitive to air pollution.
No, snow does not occur in Chiang Mai. Even during the coolest months, temperatures remain well above freezing, and the region’s tropical climate ensures snow is extremely unlikely.
The warmest month, with the highest average maximum temperature, is April (36.5 °C). The month with the lowest average maximum temperature is December (28.6 °C). Overall, the average maximum temperature over the whole year is 32.2 °C.
The month with the highest average minimum temperature is June (24 °C). The coldest month, with the lowest average minimum temperature, is January (14.9 °C). Overall, the average minimum temperature over the whole year is 20.8 °C.
The wettest month, with the highest amount of precipitation, is August (215.3 mm). The driest month, with the least amount of precipitation, is January (4.3 mm). Over the whole year there are 1,131.7 mm of rainfall on average.
The month with the most days of rain is September (19.9 days). The month with the fewest days of rain is January (0.9 days). Over the whole year there are 112.7 days of rain on average.
The month with the highest average relative humidity is September (82.1 %). The month with the lowest average relative humidity is March (52 %). The overall average relative humidity over the whole year is 70.8 %.
The months with the longest days, so the most daylight, are June and July (Average daylight: 13 h). The month with the shortest days, so the least daylight, is December (Average daylight: 11 h). Over the whole year there are 11.9 h of daylight per day on average.
The month with the most sunshine per day is February (Average sunshine: 9.1 h). The month with the least sunshine per day is September (Average sunshine: 4.9 h). Over the whole year there are 6.8 h of sunlight per day on average.
The months with the highest average UV index are March, April, May, June, July, August and September (UV index: 12). The month with the lowest average UV index is December (UV index: 8). Over the whole year the average UV index is 11.
