Nanjing weather in September
In September, Nanjing has an average high of 28 °C83 °F and an average low of 19 °C66 °F, with about 94 mm3.7 in of precipitation. It is the 4th warmest month of the year and ranks 5th for precipitation.
How September compares with other months
Compared with August, September is 4.4 °C7.9 °F cooler on average and drier by 62 mm2.4 in. Compared with October, September is 5.7 °C10.3 °F warmer on average and wetter by 39 mm1.5 in. Daylight lasts about 12.3 hours around the middle of the month. Average relative humidity is 78% and the average cloud amount 64%.
Is September a good time to visit Nanjing?
September is not among the most comfortable months by our comfort score: it is hot (average high 28 °C83 °F), it is fairly wet (94 mm3.7 in) and it is humid (78%). The most comfortable months in Nanjing are April and May and October.
What to wear in September
For Nanjing in September, pack light summer clothes such as T-shirts, shorts or light dresses and an umbrella or light rain jacket.
September in nearby places
Other months in Nanjing
- January7 °C44 °F / −3 °C27 °F
- February10 °C50 °F / 0 °C31 °F
- March16 °C60 °F / 4 °C39 °F
- April22 °C72 °F / 10 °C50 °F
- May27 °C81 °F / 16 °C60 °F
- June31 °C87 °F / 20 °C69 °F
- July32 °C90 °F / 25 °C76 °F
- August32 °C89 °F / 24 °C75 °F
- September28 °C83 °F / 19 °C66 °F
- October23 °C74 °F / 12 °C54 °F
- November17 °C62 °F / 6 °C42 °F
- December9 °C48 °F / −1 °C30 °F
Frequently asked questions
How warm is Nanjing in September?
In September the average high in Nanjing is 28 °C (83 °F) and the average low is 19 °C (66 °F).
Does it rain a lot in Nanjing in September?
On average about 94 mm (3.7 in) of precipitation falls in September; it ranks 5th of the 12 months.
Is September the warmest month in Nanjing?
No. The warmest month in Nanjing is July, with an average high of 32 °C (90 °F). The coldest month is January, with an average low of -3 °C (27 °F).
How long is the day in Nanjing in September?
In the middle of September the day in Nanjing lasts about 12.3 hours from sunrise to sunset. The value is calculated from the position of the city and the sun.
How humid is Nanjing in September?
The average relative humidity in September is about 78%. Combined with warm days, it can feel muggy.
How cloudy is Nanjing in September?
On average about 64% of the sky is covered by cloud in September. This is the mean cloud amount from satellite data, not the number of sunny days.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.