September weather forecast
Shanghai, China

As summer turns into autumn, September sees a slight decrease in the temperature levels. Although having a high amount of rainfall at 87mm (3.43"), the sea temperature remains warm, making beach outings possible. The UV index begins to decrease, making it safer for tourists to explore the city. While the sun sets a little earlier, locals and visitors can still enjoy the vibrant nightlife that Shanghai offers. In general, September provides a comfortable weather for visitors to navigate the bustling cityscape of Shanghai.

Temperature

September's arrival coincides with a soft drop in the average high-temperature, subtly decreasing from August's tropical 31.5°C (88.7°F) to a warm 27.9°C (82.2°F). Shanghai records an average low-temperature of 22.4°C (72.3°F) throughout the month of September.

Heat index

The heat index in September is calculated to be a hot 31°C (87.8°F). Fatigue might occur with continuous exposure and activity, potentially causing heat cramps.
It is noted that heat index values are ascertained for locations in the shade and with gentle breezes. The heat index might be elevated by 15 Fahrenheit (8 Celsius) degrees due to direct sun exposure.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is an amalgamation of air temperature and humidity to express the equivalent perceived temperature. Additional elements including metabolic differences, the level of physical activity, and attire have a role in shaping the individual's temperature perception. Consider the sun's direct rays and their impact; they can potentially increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.

Humidity

In Shanghai, the average relative humidity in September is 75%.

Rainfall

In Shanghai, China, in September, it is raining for 9.1 days, with typically 87mm (3.43") of accumulated precipitation. Throughout the year, there are 120.8 rainfall days, and 1166mm (45.91") of precipitation is accumulated.

Sea temperature

In September, the average sea temperature is 25°C (77°F).
Note: For swimming, diving, or other water activities, the temperature range of 25°C (77°F) to 29°C (84.2°F) is perceived as exceptionally enjoyable and comfortable even for prolonged periods.

Daylight

The average length of the day in September is 12h and 22min.
On the first day of the month, sunrise is at 05:30 and sunset at 18:17. On the last day of September, sunrise is at 05:47 and sunset at 17:40 CST.

Sunshine

In September, the average sunshine is 5.6h.

UV index

In Shanghai, the average daily maximum UV index in September is 9. A UV Index value of 8 to 10 symbolizes a very high threat to health from unprotected exposure to Sun's UV rays for the average person.
Note: A daily maximum UV index of 9 in September translates into the following instructions:
Precautions are essential; the risk of damage to unprotected skin and eyes is too high. To the best of your ability, limit your exposure to the sun between the hours of 10 a.m. and 4 p.m., when UV radiation is at its peak. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation. After every outdoor workout or swim, liberally apply and frequently reapply a broad-spectrum SPF 30+ sunscreen. Be cautious! Sand and water surfaces make the Sun's UV rays more potent.