Destination guide
Chiang Mai weather by month
December to February is the best time to visit Chiang Mai for warm days, cooler evenings and little rain. Daytime averages range from 27°C to 31°C, with nights as cool as 16°C, so outdoor plans are easier to manage than in the hotter months. February has the strongest balance of sunshine and dry weather. The main trade-off through the year is straightforward: spring brings stronger heat, while summer brings frequent rain and much less sunshine.
- Hottest month
- 35.7°CApril
- Coolest month
- 27.0°CDecember
- Rain per year
- 1138mmaverage total
- Flight from London
- 12h/dayLong-haul (7 h+) · estimated
Chiang Mai, month by month
Month-by-month detail pages exist for our most searched destinations; for Chiang Mai the 12-month table below carries the full picture.
A little perspective
Chiang Mai through the year
Every month at a glance; "best" marks our three top months on warmth, dryness and sunshine.
| Month | Day | Night | Sun/day | Rain mm | Rainy days | Days 25°C+ |
|---|---|---|---|---|---|---|
| Januarybest | 28.0°C | 16.1°C | 8.1 | 9 | 2 | 91% |
| Februarybest | 31.1°C | 18.3°C | 9.3 | 3 | 1 | 99% |
| March | 34.2°C | 21.4°C | 9.2 | 12 | 2 | 99% |
| April | 35.7°C | 24.3°C | 8.0 | 31 | 5 | 100% |
| May | 33.0°C | 24.5°C | 4.0 | 108 | 14 | 99% |
| June | 30.9°C | 24.1°C | 1.2 | 133 | 20 | 100% |
| July | 29.8°C | 23.7°C | 0.9 | 194 | 23 | 100% |
| August | 29.1°C | 23.4°C | 0.8 | 258 | 26 | 99% |
| September | 29.2°C | 22.9°C | 1.8 | 241 | 24 | 100% |
| October | 28.9°C | 21.6°C | 4.3 | 113 | 16 | 97% |
| November | 28.3°C | 18.9°C | 6.7 | 24 | 4 | 95% |
| Decemberbest | 27.0°C | 16.0°C | 7.3 | 12 | 2 | 86% |
Day = average daytime high, night = average night-time low, 1991-2020.Sun is hours per day; rainy days count 1 mm or more.
Day, night and sea
Monthly average temperatures, 1991-2020
- Day
- Night
Best months here
On warmth, low rainfall and sunshine, start with these.
When to go to Chiang Mai
For beach weather, look at months where the daytime average clears 25°C and rainy days stay low: January, February, March, April, May, June, July, August, September, October, November, December. August is the wettest month (258 mm, about 26 rainy days) and February the driest (3 mm).
Getting there
A direct flight from London Gatwick to Chiang Mai International Airport (CNX, 4 km from Chiang Mai) takes roughly 12 h - long-haul (7 h+) by UK standards. Time-zone: Asia/Bangkok.
Records and extremes, 1991-2020
The hottest day recorded in Chiang Mai between 1991 and 2020 reached 40.8°C on 16 April 1991; the coldest fell to 5.6°C on 26 December 1999. In April one day in ten tops 38.9°C and about 95% of days pass 30°C; in December one night in ten drops to 11.8°C or below. The wettest single month of the period was August 2019 with 577 mm, against a August average of 258 mm.
Sunrise, sunset and daylight in Chiang Mai
Local time on the 15th of each month; daylight-saving rules as of 2020.
| Month (15th) | Sunrise | Sunset | Daylight | Sunshine/day |
|---|---|---|---|---|
| January | 07:00 | 18:06 | 11.1 h | 8.1 h |
| February | 06:53 | 18:24 | 11.5 h | 9.3 h |
| March | 06:32 | 18:34 | 12.0 h | 9.2 h |
| April | 06:07 | 18:41 | 12.6 h | 8.0 h |
| May | 05:50 | 18:51 | 13.0 h | 4.0 h |
| June | 05:47 | 19:02 | 13.3 h | 1.2 h |
| July | 05:55 | 19:05 | 13.2 h | 0.9 h |
| August | 06:05 | 18:52 | 12.8 h | 0.8 h |
| September | 06:12 | 18:27 | 12.3 h | 1.8 h |
| October | 06:18 | 18:02 | 11.7 h | 4.3 h |
| November | 06:31 | 17:46 | 11.3 h | 6.7 h |
| December | 06:49 | 17:49 | 11.0 h | 7.3 h |
November to February: the easiest weather for outdoor plans
November marks a clear improvement after the wetter months, with rain becoming much less frequent and evenings cooling down. December is the coolest month, but its 27°C daytime average still calls for light clothing rather than a winter wardrobe. January offers similar conditions, making it a good choice if you prefer warmth without the stronger spring heat. February is warmer at 31°C and has just 1 rain day on average, so it suits travellers who value dry outdoor time most. Pack a light layer for early starts and evenings, especially in December and January, when nights average 16°C. Midday can still feel hot, even in this more comfortable season.
March to May: stronger heat, then a wetter turn
March remains relatively dry and sunny, but its 34°C daytime average makes shade and breaks more important. April is the hottest month, averaging around 36°C by day and 24°C at night, so evenings offer less relief than in winter. Put more demanding outdoor plans earlier in the day and leave room for indoor breaks around midday. May brings a different compromise: daytime temperatures ease to 33°C, but rain becomes much more frequent, averaging 14 rain days, while sunshine drops to 4 hours. This period suits travellers who cope well with heat and can keep their plans flexible; it is less appealing if comfortable walking weather is your priority.
June to October: frequent rain, with improvement towards the end
June, July and August bring a run of cloudy, frequently wet weather, with only 1 hour of sunshine a day on average. August is the wettest month and averages 26 rain days, making it a poor choice if reliable sunshine matters most. September remains frequently wet, although sunshine starts to recover. October is a more workable compromise: daytime temperatures average 29°C, sunshine increases to 4 hours and rain becomes less frequent, though waterproofs still deserve space in your bag. Across this period, choose light clothing and footwear that can cope with getting wet, and keep indoor alternatives available. The lower daytime temperatures do not bring winter-like evenings; nights remain warm.
A little more detail
Chiang Mai weather FAQs
Plain answers, grounded in the averages.
What is the best time to visit Chiang Mai?
Judged on warmth, low rainfall and sunshine, the best months in Chiang Mai are February, January and December. April is the hottest month (average high 35.7°C) and December the coolest (27.0°C).
How many months a year is Chiang Mai over 25°C?
12 months in Chiang Mai average a daytime high of 25°C or more, and 12 average 20°C or more.
When is the rainy season in Chiang Mai?
August is the wettest month in Chiang Mai (258 mm on average) and February the driest (3 mm). Annual rainfall averages 1138 mm.
What is the hottest temperature recorded in Chiang Mai?
The hottest day recorded in Chiang Mai between 1991 and 2020 reached 40.8°C on 16 April 1991; the coldest fell to 5.6°C on 26 December 1999. Records come from daily data for 1991-2020, not from a single station's all-time history.
Which month is best for sunshine and little rain?
February offers the strongest combination, with 9 hours of sunshine a day and just 1 rain day on average. March matches that sunshine but is hotter, so February is the more comfortable choice for spending plenty of time outdoors.
Will I need warm clothes in Chiang Mai?
A light layer is useful for evenings and early starts in December and January, when nights average 16°C. Daytime temperatures remain warm, so pack mainly light clothing. In the hotter and wetter months, overnight temperatures stay much higher.
Is October a good alternative to the driest months?
October can suit a flexible trip, with daytime averages of 29°C and improving sunshine. The catch is rain: it still averages 16 rain days. November is a better choice if you want fewer weather interruptions without moving into the hottest part of the year.
See also: Thailand weather by month · where else is hot in April
About these averages
ERA5-Land climate reanalysis via Open-Meteo (11 km grid), 1991-2020
Averages computed from daily values at Chiang Mai. Sunshine hours are estimated from average cloud cover.Records are the highest and lowest daily values in that 30-year period, not all-time records. These are climate averages, not a forecast for your trip. How we measure holiday weather
- Hot · 25°C+
- Warm · 20°C to below 25°C
- Mild · 15°C to below 20°C
- Cool · below 15°C