Chennai
India
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Chennai, India

A staircase to the front entrance of the Ramakrishna Temple in Chennai, India
A staircase to the front entrance of the Ramakrishna Temple in Chennai, India
September, the last month of the rainy (monsoon) season, in Chennai, is another hot month, with average temperature ranging between min 25.5°C (77.9°F) and max 33.9°C (93°F).

Temperature

In September, the average high-temperature is essentially the same as in August - a still tropical 33.9°C (93°F). In September, in Chennai, India, the average low-temperature is 25.5°C (77.9°F).

Heat index

The average heat index in September is evaluated at a burning hot 47.4°C (117.3°F). Beware - heat cramps and heat exhaustion are very likely. Heatstroke is imminent with prolonged activity.
Note that heat index values are valued for light wind and location in the shade. With the exposure to direct sunlight, the heat index may be increased by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel', 'feels like', 'felt air temperature', or 'apparent temperature', is what the temperature feels like to the human body when the air temperature is combined with the relative humidity.

Humidity

In Chennai, the average relative humidity is 72%.

Rainfall

In September, in Chennai, the rain falls for 7.1 days. Throughout September, 137.3mm (5.4") of precipitation is accumulated. Throughout the year, there are 59.1 rainfall days, and 1391.5mm (54.8") of precipitation is accumulated.

Sea temperature

In Chennai, the average seawater temperature in September is 29.3°C (84.7°F).
Note: Water temperature between 25°C (77°F) and 29°C (84.2°F) is regarded as very warm and enjoyable by all. With these temperatures, water activities are pleasurable, without feeling uncomfortable for prolonged periods.

Daylight

The average length of the day in Chennai is 12.2h.

Sunshine

In September, the average sunshine is 6.6h.

UV index

Months with the highest UV index are February through September, with an average maximum UV index of 12. A UV Index value of 11, and more, symbolizes an extreme threat to health from unprotected exposure to the Sun's UV rays for the ordinary person.
Note: The average daily UV index of 12 in September transform into the following instructions:
Take all necessary precautions, as unprotected skin can burn in minutes. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun. Even on cloudy days, a sunscreen with a minimum 30 sun protection factor should be generously applied and frequently re-applied, including after every swim or outdoor exercise. Beware! The strength of the UV rays is significantly increased by the reflection of the water and sand.

What is the temperature in September in Chennai?

In Chennai, India, in September, the average high-temperature is 33.9°C (93°F), and the average low-temperature is 25.5°C (77.9°F).

What is the average humidity in September in Chennai?

In Chennai, the average relative humidity in September is 72%.

How much does it rain in Chennai in September?

In September, the rain falls for 7.1 days. Throughout September, 137.3mm (5.4") of precipitation is accumulated.

How warm is the water in September in Chennai?

In Chennai, in September, the average water temperature is 29.3°C (84.7°F). Water temperature between 25°C (77°F) and 29°C (84.2°F) is regarded as very warm and enjoyable by all. With these temperatures, water activities are pleasurable, without feeling uncomfortable for prolonged periods.

What is the average length of the day in September in Chennai?

In Chennai, the average length of the day in September is 12.2h.

How many hours of sunshine does Chennai have in September?

In Chennai, the average sunshine in September is 6.6h.

What is the month with the highest UV index in Chennai?

February through September, with an average maximum UV index of 12, are months with the highest UV index in Chennai, India.

What is the UV index reading in September in Chennai?

In Chennai, India, the average daily maximum UV index in September is 12. A UV Index reading of 11, and higher, represents an excessive health risk from unsafe exposure to the Sun's UV rays.
Average temperature in September - Chennai, India
  • Average high temperature in September: 33.9°C

The warmest month (with the highest average high temperature) is June (36.9°C).
The month with the lowest average high temperature is December (28.5°C).

  • Average low temperature in September: 25.5°C

The month with the highest average low temperature is May (27.9°C).
The coldest month (with the lowest average low temperature) is January (20.9°C).

Average humidity in September - Chennai, India
  • Average humidity in September: 72%

The month with the highest relative humidity is November (78%).
The month with the lowest relative humidity is June (57%).

Average rainfall in September - Chennai, India
  • Average rainfall in September: 137.3mm

The wettest month (with the highest rainfall) is November (407.4mm).
The driest month (with the lowest rainfall) is February (2.2mm).

Average rainfall days in September - Chennai, India
  • Average rainfall days in September: 7.1 days

The month with the highest number of rainy days is November (11.7 days).
The month with the lowest number of rainy days is March (0.3 days).

Average sea temperature in September - Chennai, India
  • Average sea temperature in September: 29.3°C

The best month for swimming (with the highest average sea temperature) is May (29.5°C).
The coldest month (with the lowest average sea temperature) is January (26.8°C).

Average daylight in September / Average sunshine in September - Chennai, India
  • Average daylight in September: 12.2h

The month with the longest days is June (Average daylight: 12.9h).
The month with shortest days is December (Average daylight: 11.4h).

  • Average sunshine in September: 6.6h

The month with most sunshine is April (Average sunshine: 9.7h).
The month with least sunshine is July (Average sunshine: 6h).

Average UV index in September - Chennai, India
  • Average UV index in September: 12

Months with the highest UV index are February, March, April, May, June, July, August and September (UV index 12).
The month with the lowest UV index is December (UV index 9).