Chiang Rai features a tropical savanna climate with three distinct seasons: a hot, dry season from March to May, a rainy monsoon season from June to October, and a cool, dry season from November to February. Temperatures range from 13°C on winter nights to highs of 37°C in April. Rainfall is heaviest in August and September, while sunshine is abundant in the dry months.
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 Rai, located in northern Thailand at an elevation of nearly 400 metres, experiences a tropical climate shaped by both its latitude and its proximity to mountain ranges. The year is divided into three main seasons. The hot season, from March to May, brings soaring daytime highs of 33–37°C, with April being the hottest month. Nights are warm but can be cooler than elsewhere in Thailand due to the altitude. Humidity is moderate to high, and rainfall is minimal until late April, when the first pre-monsoon showers may begin. Sunshine is plentiful, with up to 9–11 hours per day in February and March.
The rainy season, from June to October, is characterised by frequent, heavy downpours and high humidity. August is the wettest month, averaging 350–390 mm of rainfall and 23–24 rainy days, though rain typically falls in short, intense bursts, often in the late afternoon or evening. Daytime highs drop slightly to 29–32°C, and nights remain warm at 21–23°C. The landscape is lush and green, and occasional flooding can occur in low-lying areas. The cool season, from November to February, is the most pleasant time of year, with daytime highs of 26–29°C, crisp mornings, and night temperatures dropping to 12–15°C in January. Rain is rare, humidity is lower, and skies are mostly clear, making this period ideal for outdoor activities and sightseeing. Chiang Rai receives about 1,900–2,000 mm of rain annually and enjoys 2,500+ hours of sunshine, with the sunniest months from January to April. Winds are generally light, with occasional breezes in the hot and rainy seasons.
| Average climate data for Chiang Rai, Thailand | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Average maximum temperature (°C) | 28 | 31 | 34 | 35 | 33 | 32 | 31 | 31 | 31 | 30 | 29 | 27 | 35 |
| Average minimum temperature (°C) | 13 | 14 | 17 | 21 | 22 | 24 | 23 | 23 | 23 | 21 | 17 | 14 | 13 |
| Average precipitation (mm) | 8 | 14 | 28 | 97 | 211 | 178 | 314 | 361 | 283 | 126 | 59 | 14 | 1,693 |
| Average rainfall days (days) | 2 | 1 | 3 | 10 | 17 | 19 | 22 | 24 | 18 | 12 | 6 | 3 | 137 |
| Average relative humidity (%) | 75 | 66 | 63 | 67 | 76 | 79 | 82 | 85 | 83 | 83 | 79 | 76 | 76 |
| 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 | 6 | 7 | 7 | 7 | 7 |
| Average UV index | 8 | 10 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 10 | 8 | 7 | 11 |
The best time to visit Chiang Rai is from November to February, during the cool, dry season. These months offer comfortable daytime temperatures (26–29°C), crisp mornings, clear skies, and minimal rainfall – ideal for exploring temples, hiking, and enjoying festivals. The air is fresher, and the lush landscapes remain green from the end of the rainy season.
The least favourable time to visit is from July to September, when the monsoon brings frequent, heavy downpours and high humidity. Travel can be disrupted by rain, muddy roads, and occasional flooding. While the region is beautifully green, outdoor activities are often limited, and leeches can be present on jungle trails.
Chiang Rai has three seasons: a hot, dry season (March–May), a rainy season (June–October), and a cool, dry season (November–February). The cool season is the most pleasant for travel, while the rainy season is lush but wet.
April is the hottest month, with daytime highs often reaching 36–37°C. Even in the coolest months, daytime temperatures can reach 26–29°C, but nights in December and January can drop to 12–15°C.
August and September are the wettest months, each with 350–390 mm of rain and over 20 rainy days. Rain falls in heavy bursts, usually in the late afternoon or evening, and can cause flooding in some areas.
Yes, Chiang Rai is humid year-round, especially during the rainy season when humidity can exceed 80%. The hot season is drier but still feels muggy, while the cool season is more comfortable with lower humidity.
Pack lightweight, breathable clothes and sun protection for the hot season, a rain jacket and waterproof shoes for the rainy season, and a jumper or jacket for cool evenings from November to February.
Snow is unknown in Chiang Rai, but winter nights (December–January) can be chilly, with lows dropping to 12–15°C. Frost is rare, and days remain warm and sunny.
Yes, especially from November to February when the weather is cool and dry. The rainy season (June–October) is best for lush scenery but can limit hiking and biking due to muddy trails and heavy showers.
The warmest month, with the highest average maximum temperature, is April (34.8 °C). The month with the lowest average maximum temperature is December (27.1 °C). Overall, the average maximum temperature over the whole year is 31.1 °C.
The month with the highest average minimum temperature is June (23.7 °C). The coldest month, with the lowest average minimum temperature, is January (12.9 °C). Overall, the average minimum temperature over the whole year is 19.3 °C.
The wettest month, with the highest amount of precipitation, is August (361.5 mm). The driest month, with the least amount of precipitation, is January (7.6 mm). Over the whole year there are 1,693 mm of rainfall on average.
The month with the most days of rain is August (24.1 days). The month with the fewest days of rain is February (1 days). Over the whole year there are 136.5 days of rain on average.
The month with the highest average relative humidity is August (85.1 %). The month with the lowest average relative humidity is March (62.8 %). The overall average relative humidity over the whole year is 76.1 %.
The month with the longest days, so the most daylight, is June (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 h). The month with the least sunshine per day is July (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: 7). Over the whole year the average UV index is 10.6.
