Weather in Hanoi in September 2025
Average weather
Average temperature in Hanoi in September
The temperature in September is +90°F on average, with a range between a maximum of +97°F during the day and a minimum of +75°F at night.
The average maximum temperature goes down 8% by the end of the month, compared with the beginning of the month, from +93°F to +91°F.
Is Hanoi warm or cold in September?
Hanoi is typically hot in September.
Maximum temperatures go up compared to the previous month from +90°F to +90°F. The minimum temperature also goes down from +79°F to +77°F.
Make sure that you pack your summer linen and swimming costumes; it’s probably going to be hot.
September is one of the warmest months in Hanoi, here is the comparison with other months:
Climate in Hanoi in September
| August | September | October | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +90°F | +90°F | +84°F | ||||
| Min. temperature | ||||||
| +73°F | +64°F | +55°F | ||||
| Max. temperature | ||||||
| +100°F | +99°F | +95°F | ||||
| Rainfall | ||||||
| 310 mm | 229 mm | 153 mm | ||||
| Wind | ||||||
| 1 m/s | 1 m/s | 1 m/s | ||||
| Humidity | ||||||
| 84% | 83% | 80% | ||||
| Air pressure | ||||||
| 1002 HPa | 1007 HPa | 1012 HPa | ||||
| Sunny days | ||||||
| 1 | 2 | 4 | ||||
| Cloudy days | ||||||
| 3 | 5 | 9 | ||||
| Rainy days | ||||||
| 25 | 21 | 17 | ||||
| Snowy days | ||||||
| 0 | 0 | 0 | ||||
September weather is still as ok as in August. The temperature levels stay the same in the area of +90°F for average maximum temperature during the day. As September arrives, the amount of rainfall goes down. On average, the rainfall volume decreases from 310 mm to 229 mm. It feels drier, as humidity decreases from 84% to 83%. The average wind speed doesn’t change much during September, staying around 1 m/s. The good news is there are likely to be more sunny days in September, from 1 to 2.
October brings much the same weather, it remains ok.
Wind
The average wind speed is 1 m/s getting up to 4 m/s which is a light breeze; barely moving the tree leaves.
The average wind speed in Hanoi is gradually decreasing during September, going from 2 m/s to 1 m/s over the course of the month.
Rain
How was the weather last September in Hanoi?
Climate Change Over the Years
The climate in Hanoi in September has not changed that much over the last 43 years.
The average temperature was the lowest in 2011 (+79°F) and the highest in 2019 (+84°F). The driest year was 2004 with only 1210 mm of rainfall, and the wettest year was 1981 with 2188 mm.
FAQ
Is September a good time to visit Hanoi?
Can you sunbathe in Hanoi in September?
Is Hanoi rainy in September?
Is it sunny in Hanoi in September?
Other cities in Vietnam
Monthly weather in Hanoi
Source of the data
For this page, we’ve looked at the typical weather in Hanoi, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.