Chennai is unusual among major Indian cities in that its heaviest rain comes not from the June-September southwest monsoon but from the northeast monsoon between October and December, when the Bay of Bengal is also at its most active for cyclones. The city’s low-lying, flat coastal geography and historically limited stormwater drainage were exposed dramatically during the 2015 floods, when sustained heavy rain left large parts of the city underwater for days. Radar and satellite tracking of approaching depressions and cyclones is especially important here ahead of the northeast monsoon season.
Rain in Chennai by month
Chennai gets about 1,253 mm (49.3 in) of rain in an average year. The wettest month is November, with 292 mm (11.5 in), and the driest is February, with 6 mm (0.2 in).
| Month | Average rain | Average temperature |
|---|---|---|
| January | 16 mm (0.6 in) | 24.1 °C (75 °F) |
| February | 6 mm (0.2 in) | 25.6 °C (78 °F) |
| March | 15 mm (0.6 in) | 28.4 °C (83 °F) |
| April | 26 mm (1.0 in) | 30.5 °C (87 °F) |
| May | 56 mm (2.2 in) | 31.5 °C (89 °F) |
| June | 68 mm (2.7 in) | 30.6 °C (87 °F) |
| July | 108 mm (4.3 in) | 29.7 °C (85 °F) |
| August | 132 mm (5.2 in) | 29.0 °C (84 °F) |
| September | 145 mm (5.7 in) | 28.3 °C (83 °F) |
| October | 264 mm (10.4 in) | 27.4 °C (81 °F) |
| November | 292 mm (11.5 in) | 25.8 °C (78 °F) |
| December | 126 mm (5.0 in) | 24.4 °C (76 °F) |
Long-term monthly averages from NASA POWER (MERRA-2 satellite reanalysis). They describe the wider area around Chennai and can differ slightly from local weather-station records.
Learn more: Hurricane Season Radar Guide · Open the full Rain Map
Frequently Asked Questions
Is it raining in Chennai right now?
The map above shows recent radar observations over Chennai, Tamil Nadu where coverage is available. Use the map legend and timestamp to interpret the imagery. A blank map over Chennai can mean no detected precipitation, missing coverage, delayed data, or rain too light for radar to detect.
How often does the Chennai rain radar update?
Updates depend on the radar provider and local network. Check the timestamp on the map for the latest available frame, and press play to compare recent observations. Radar imagery can lag conditions on the ground.
Can I see if a storm is heading toward Chennai?
Press play to compare recent radar frames over Tamil Nadu and see the direction of detected rain. This can help you assess approaching showers near Chennai, but storms can grow or change direction; check your local weather service for forecasts and warnings.
Is this Chennai rain radar free to use?
Yes, completely free – no account, app download, or sign-up required. It works in any browser on desktop and mobile.