September · Vietnam
Best time to visit Hanoi in September Weather, crowds & prices
Weather in Hanoi in September
Average temperature 27°C, 378 mm of rain, about 15 days with 6+ hours of sunshine and 87% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
September score
2.9/10
Ranked #9 of 12 months
- Avg temp
- 27°C
- Rainfall
- 378 mm
- Humidity
- 87%
- Days with 6h+ sun
- 15
- Crowd Density
- Quiet / Uncrowded
- Average Expenses
- $ · Budget Friendly ($)
September in Hanoi scores 2.9/10 for sightseeing and cultural travel - ranked #9 of 12. Expect around 27°C, 378 mm of rain, and roughly 15 days with 6+ hours of sunshine this month.
Old Quarter alleys, lake walks, and street-noodle mornings peak January through March.
September in Hanoi — the hardest end of the year
Days in September average 27°C (81°F) and humidity near 87% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
Expect monsoon-level rainfall at 378 mm: only about 15 days with 6+ hours of sunshine across the month, and stretches of heavy rain are normal.
That is 2.9/10 on the same scale — 9th of 12 months, versus 8.5/10 for the best month here.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Budget for low-season pricing, and crowds are light for this destination.
If your dates are flexible, November is materially better in Hanoi — 5.6 points higher on the same scale.
Frequently asked
- What is the weather like in Hanoi in September?
- In September, Hanoi averages 27°C, 378 mm of rain, and about 15 days with 6+ hours of sunshine. Its climate-comfort score is 2.9/10.
- Is September a good time to visit Hanoi?
- September earns a 2.9/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Hanoi in September?
- Expect about 378 mm of rain in September. Average humidity is 87% and there are about 15 days with 6+ hours of sunshine.
Curated in Hanoi
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Hanoi, Vietnam. Live activities and tours from GetYourGuide, matched to this destination.