Thailand Bangkok Weather in September — Climate Guide
September in Bangkok is Below Average
September is Below Average for Bangkok.
September is Bangkok's wettest month — 261mm cumulative rainfall over 18 rainy days. Storms become slightly less predictable than July-August; some days have continuous afternoon-evening rain rather than the typical 1-2 hour pattern.
The upside: hotel prices remain at year-low. Tourist crowds at deep minimum. Major sights (Grand Palace, Wat Pho) often have less than 10% of January-February crowd density.
Travel score
Bangkok September Weather Stats
Avg High
33°C
Avg Low
25°C
Rainy Days
18
261mm total
Sunshine
6h
Daily avg
Humidity
78%
Very humid
UV Index
10
Very high
Wind
12 km/h
Gusts 24
Crowds
Quiet
At attractions
September Sunrise & Sunset
Air Quality
PM2.5
23 μg/m³
PM10
35 μg/m³
Status
Moderate
Feels-Like Temperature & Wind
Feels like
Daytime
39°C
Nighttime
26°C
Humidity and wind affect how the actual temperature feels.
Wind
12 km/h
Max gust 24 km/h
Activities Recommended for September
September Travel Pros & Cons
Pros
- Lowest hotel prices of the year
- Minimal tourist crowds
- Authentic non-touristy local experience
Cons
- Wettest month of the year (261mm)
- Some day trips not viable
- Outdoor activities frequently rained out
September Events & Festivals
- Heaviest rainfall month of the year (261mm average)
- Bangkok International Film Festival (varies)
- Monsoon at peak intensity
Bangkok in September — Full Picture
September is Bangkok's wettest month — 261mm cumulative rainfall over 18 rainy days. Storms become slightly less predictable than July-August; some days have continuous afternoon-evening rain rather than the typical 1-2 hour pattern.
The upside: hotel prices remain at year-low. Tourist crowds at deep minimum. Major sights (Grand Palace, Wat Pho) often have less than 10% of January-February crowd density.
Bangkok International Film Festival (varies year to year) is the city's main film event — international films at SF World Cinema and major mall theaters. Tickets $5-10.
This is the month most travel guides recommend avoiding, but for budget travelers willing to embrace the rain rhythm, September can deliver an authentically local Bangkok experience without crowds. Yaowarat at night, Chatuchak weekend market, sky bar evenings — all available with shorter queues.
For day trips, Ayutthaya is genuinely difficult this month. Stay city-focused. Phuket and Krabi flight prices drop dramatically but ferry to islands frequently cancelled.
What to Wear & What to Pack
Light tropical + folding umbrella. Quick-dry essential. Rainy-day appropriate footwear (sandals or quick-dry sneakers).
Packing Checklist
Seasonal Weather Overview
Spring (Mar·Apr·May)
35°C
25.7°C
7/mo
Summer (Jun·Jul·Aug)
33°C
25.3°C
15.3/mo
Autumn (Sep·Oct·Nov)
Current32.7°C
24.3°C
13/mo
Winter (Dec·Jan·Feb)
32°C
21.7°C
1.3/mo
Bangkok Monthly Weather Comparison
| Month | High | Low | Rain | Sun | Humid | UV | Crowd | Price |
|---|---|---|---|---|---|---|---|---|
| January (Best) | 32° | 21° | 1d·9mm | 9h | 65% | 9 | Very busy | Peak |
| February (Best) | 33° | 23° | 2d·28mm | 9.5h | 65% | 10 | Busy | Peak |
| 35° | 25° | 2d·30mm | 8.5h | 67% | 11 | Moderate | Shoulder | |
| 36° | 26° | 5d·65mm | 8h | 70% | 11 | Busy | Peak | |
| 34° | 26° | 14d·220mm | 7.5h | 75% | 10 | Quiet | Low season | |
| 33° | 26° | 14d·169mm | 7h | 75% | 10 | Quiet | Low season | |
| 33° | 25° | 16d·171mm | 6.5h | 76% | 10 | Quiet | Low season | |
| 33° | 25° | 16d·184mm | 6.5h | 76% | 10 | Quiet | Low season | |
| 33° | 25° | 18d·261mm | 6h | 78% | 10 | Quiet | Low season | |
| 33° | 25° | 16d·197mm | 6.5h | 76% | 10 | Quiet | Low season | |
| November (Best) | 32° | 23° | 5d·49mm | 8h | 70% | 9 | Busy | Shoulder |
| December (Best) | 31° | 21° | 1d·9mm | 9h | 65% | 9 | Very busy | Peak |
View Other Months
Bangkok September Hotel Picks
Frequently Asked Questions
Is September a good time to visit Bangkok?
Bangkok in September is Below Average. Tourist crowds are quiet and flight/hotel prices are low season.
What's the average temperature in Bangkok in September?
Bangkok September averages a high of 33°C and a low of 25°C.
Does it rain much in Bangkok in September?
Bangkok September averages 261mm of rainfall over about 18 rainy days.
What should I wear in Bangkok in September?
Light tropical + folding umbrella. Quick-dry essential. Rainy-day appropriate footwear (sandals or quick-dry sneakers).
What time are sunrise and sunset in Bangkok in September?
Bangkok September sunrise is 06:08 and sunset is 18:18, with 12h 10m of daylight.
What's the air quality like in Bangkok in September?
Bangkok September air quality (AQI) averages 55, rated Moderate. PM2.5 averages 23μg/m³.
What activities are recommended in Bangkok in September?
In September, Bangkok is great for Bangkok International Film Festival, Yaowarat night markets, Indoor museum culture.
Is September peak season in Bangkok?
Bangkok September crowds are quiet and prices are low season. You can travel relatively comfortably without long queues.
Best Months to Visit Bangkok
View Other Months
Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.