Season by season
Cool & dry season
November to February is cool, dry and clear: the season for Phu Chi Fa’s cloud sea, cherry blossom on the high ridges and comfortable trekking. Nights are cold in the hills, where temperatures can fall to single figures.
Hot season
March to May is hot, and from about late February to mid-April smoke from burning fields often blankets the far north, hiding the mountains and making the air unhealthy. This is the least rewarding time for viewpoints.
Rainy season & sea conditions
From June to October rain falls most days, usually in bursts. The landscape turns deep green, waterfalls run hard and rice terraces fill; forest trails are muddy, and the Mekong runs high and brown.
Month by month
| Month | Avg high | Avg low | Rainfall | Crowds |
|---|---|---|---|---|
| January | 30°C | 15°C | 10 mm | Very busy |
| February | 33°C | 16°C | 10 mm | Very busy |
| March | 35°C | 20°C | 20 mm | Busy |
| April | 36°C | 23°C | 55 mm | Busy |
| May | 34°C | 24°C | 150 mm | Quiet |
| June | 33°C | 24°C | 120 mm | Quiet |
| July | 32°C | 24°C | 150 mm | Busy |
| August | 32°C | 24°C | 220 mm | Busy |
| September | 32°C | 23°C | 210 mm | Quiet |
| October | 31°C | 22°C | 120 mm | Busy |
| November | 30°C | 19°C | 45 mm | Very busy |
| December | 29°C | 16°C | 15 mm | Very busy |
Temperatures and rainfall are approximate long-term averages for the nearest weather station; individual years vary, and mountain areas are cooler than the figures shown.
Festivals & events
- December–January: Cherry blossom and tea festivals on Doi Mae Salong and the surrounding ridges.
- January: Akha and Lisu New Year celebrations in hill villages, on dates set by each community.
- April: Songkran, Thai New Year, celebrated with water and processions.
- November: Loy Krathong, with floats released on the Kok River.
Our advice
Aim for November to January for views and cool hiking, or July to September if you like green hills and do not mind showers. In March and April, check air quality before you commit. See also when to go to Thailand.
