Climate Overview
The climate in Chiang Rai is hot. The average annual temperature is 26°C and approximately 1491mm of precipitation falls per year. August is the wettest month, receiving around 346mm of rainfall. Chiang Rai is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: April, May, March. The coldest months are January, December, February, when temperatures can drop to 15°C.
Temperature
Temperatures in Chiang Rai vary considerably across the year, with a 21°C difference between the coldest and warmest months. April is the hottest month, with daytime highs reaching 36°C and an average of 29°C. January is the coolest month, with minimum temperatures around 15°C and an average of 21°C. On average, daily temperatures fluctuate by about 11°C between overnight lows and afternoon highs. The sharpest temperature change occurs between February and March, with a 4°C shift in average temperatures.
Precipitation
Chiang Rai is a fairly wet location, receiving approximately 1491mm of precipitation annually, which averages out to around 124mm per month. The wettest month is August, averaging 346mm of rainfall. July and September also tend to see above-average precipitation. The driest month is February, with just 4mm. That's 342mm less than August, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.
Wind
Chiang Rai is relatively calm, with an average annual wind speed of 1km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is June, averaging 2km/h, though still comfortable for most outdoor activities. The calmest conditions occur in January, with average winds dropping to 1km/h, making it an ideal period for wind-sensitive activities. Wind speeds vary significantly across the year, with a 1km/h difference between the calmest and windiest months. This level of variation is worth factoring into travel plans.
Seasons
91 days until Autumn
It is currently summer in Chiang Rai, which began on June 21, 2026. Chiang Rai is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in April at around 36°C, while the coldest stretch bottoms out in January near 15°C. Autumn is next, beginning on September 23, 2026 — 91 days from now.
Spring
Temperatures range from 19 to 36°C. Precipitation is moderate at around 246mm for the season, averaging 82mm per month. Winds are generally light, averaging 2km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 25 to 33°C. Rainfall is heavy, totalling around 797mm across the season with a monthly average of 266mm. Winds are generally light, averaging 2km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 20 to 32°C. Rainfall is heavy, totalling around 385mm across the season with a monthly average of 128mm. Winds are generally light, averaging 1km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 15 to 32°C. Rainfall is relatively light, with around 63mm over the season and a monthly average of 21mm. Winds are generally light, averaging 1km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Best Time to Visit
The best time to visit Chiang Rai is during January, February, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 22°C with modest rainfall averaging 26mm per month. By contrast, April can be uncomfortably hot with temperatures reaching 36°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.
Monthly Climate Data
The table below shows monthly climate averages for Chiang Rai based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
