Chiang Mai · Thailand
September
Still deep monsoon — quietest and cheapest month, but sustained heavy rain limits outdoor activity.
Worth considering
#10 of 12 months
There are better months for Chiang Mai — see the full ranking below.
See when to go instead →Climate
High
31°C
Low
20.5°C
Rain
165mm
Sun
5.5hrs/day
30-year climate normals · Open Meteo ERA5
How September scores in Chiang Mai
Weather
Below average
Value
Outstanding
Crowds
Outstanding
Events
Below average
Atmosphere
Above average
What you gain in September
- ↑Virtually no international tourists: the old city, temples, and markets feel entirely local
- ↑Rock-bottom prices across all categories — same quality at 50% below peak
- ↑Waterfalls at maximum flow: Sticky Falls and Huay Kaew are spectacular if rain allows the drive
What you sacrifice
- ↓165mm of rain with the highest humidity of the year: outdoor plans genuinely constrained
- ↓Some trekking companies suspend operations entirely until October
- ↓Long stretches of overcast days with muted light — not ideal for photography
How September compares to November (best month)
| Factor | September | November ★ |
|---|---|---|
| Weather | 3 | 10 |
| Value | 9 | 5 |
| Crowds | 9 | 5 |
September in other destinations
Lisbon (24.6°C)Barcelona (25.5°C)Tokyo (28.1°C)Bali (30.4°C)Santorini (24.1°C)Paris (21.6°C)New York (23.9°C)Marrakech (31.6°C)Amsterdam (18.8°C)Maldives (30.2°C)Rome (26.5°C)Bangkok (31°C)Istanbul (24.2°C)Vienna (22.1°C)Seoul (25.1°C)Dubrovnik (24.9°C)Rio de Janeiro (27.3°C)Kyoto (28.6°C)Phuket (31°C)Cape Town (19°C)Prague (21°C)Amalfi Coast (27°C)Mexico City (22°C)Medellín (28°C)Fiji (27°C)London (20°C)Sydney (20°C)Iceland (10°C)Tulum (32°C)Dubai (39°C)Singapore (32°C)Hoi An (31°C)Miami (32.8°C)Florence (26.3°C)Queenstown (12.5°C)Madrid (28.7°C)
Climate data: 30-year normals (1991–2020) from Open Meteo ERA5 reanalysis. Scores compare months within Chiang Mai, not across destinations. Methodology →