Chiang Mai Weather in September 2026: what to expect (4.5/10)

The month in detail

What to expect in September

September falls in the wet season in Chiang Mai. Showers are often brief but intense. With 86.0% of rainy days, always have indoor alternatives planned.

September ranks 9 out of 12 months in Chiang Mai. Compared to August: 10 pts fewer rainy days, +1.5h of sun per day.

This month's conditions

What it's like in September

UV index

7 · high

sunscreen and hat advised

Feels like

very humid

24°

Daylight

12.1h of daylight

Air quality

good

AQI 35

Compare

Is September the right month?

The best month in Chiang Mai is February (9.1/10), 4.6 pts higher than September.

See February →See all 12 months →

Context

Our verdict

Chiang Mai is the cultural capital of northern Thailand: 130,000 inhabitants in the old town, 200 temples, former capital of the Lan Na kingdom (1296-1558). January is my favourite month (9.1/10): 17-28°C, 13% rain, ideal temperature, clear skies.

Read Gilles' full review →

Book

Plan your trip

Hotels at their lowest outside peak season, highest on comfortable months. Shoulder seasons offer a good price/climate compromise.

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Stay

Hotels & rentals · Chiang Mai

Expedia →

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Activities

Tours, tickets, experiences

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Flights

Multi-airline comparator

Kiwi →

🎟️ Activities & tours · Chiang Mai

GetYourGuide selection · free cancellation

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Affiliate link · GetYourGuide

Practical info

What you need to know before you go

Three angles: the country (language, currency, safety, budget), the year-round climate, and the specifics of a tropical stay.

Country · Thailand

🗣️LanguageThai

💶CurrencyThai Baht (฿)

🚗DrivingLeft-hand

🛡️Safety ⓘSafe · 2/5

💰Cost of living ⓘCheap · 2/5

🌡️ Climate

🌍Climate typeTropical

📈Climate trendData unavailable

🔥Hottest monthApril · 36°C

❄️Coolest monthJanuary · 28°C

🌧️Rainiest month ⓘAugust · 96%

🏝️ Tropical stay

🌞Dry season ⓘMay → Sep

🌧️Wet season ⓘDec → Mar

🌀Cyclones ⓘSeason Nov-Apr

Explore

Other destinations in September

If September doesn't convince you for this destination, compare with others.

Similar climate

Nearby

Luang PrabangLaos352 km

VientianeLaos393 km

MandalayMyanmar465 km

BangkokThailand584 km

Other top picks

Cape VerdeCape Verde5.3

SalCape Verde5.6

Marsa AlamEgypt5.8

Sharm el-SheikhEgypt5.8

HurghadaEgypt5.9

← August October →

🗺️ See all 754 destinations on the map

Location

Where is Chiang Mai ?

Global position + regional geographic context.

🌍 World

🔍 Geographic context

Thailand

Tropical climate with a 9.1 → 4.3 gap between best and worst month. 10 years of ERA5 data to choose by project.

18.79°N · 98.98°E

Questions

Frequently asked questions

What is the best time to visit Chiang Mai?

February is the best month with 30.0°C highs, 18.0°C lows, 8.9h of sunshine and 6.0% rainy days. The months of February & January offer comparable conditions.

How many hours of sunshine does Chiang Mai get in February?

Chiang Mai averages 8.9 sunshine hours per day in February. It is the sunniest month with a climate score of 8.7/10.

What is the rainiest month in Chiang Mai?

July is the most unfavourable month with July has the lowest climate score of the year and the lowest climate score of the year.

What are the temperatures at night in Chiang Mai in February?

In February, overnight lows reach 18.0°C, while afternoon highs average 30.0°C.

Is Chiang Mai good in winter?

In winter (December-February), Chiang Mai scores 8.6/10 on average — Decent period conditions for cultural visits.. The best month overall remains February with a score of 8.7/10.

When should you avoid Chiang Mai?

July is the most difficult month to visit Chiang Mai, with July has the lowest climate score of the year. Climate conditions are at their lowest of the year during this period.

Do you need sun protection in Chiang Mai in September?

The average UV index reaches 7 in September in Chiang Mai (high), with about 12.1h of daylight. Sunscreen and hat advised.