According to Skymet Meteorology Division in India, Chennai has observed four rainy days out of seven during the last leg of the Southwest Monsoon. The city has recorded 59 mm of rainfall on September 04, 16 mm on September 06, 25 mm on September 16 and 31 mm on September 22. Remaining days have either observed light or no rains or single digit rainfall.
Tamil Nadu is a rain shadow area, due to which the normal rainfall is also not very high during the Southwest Monsoon season. However, the coastal parts and hilly parts receive good showers. It was indeed one of the very few pockets that observed a surplus of 4% in June, while the entire country was experiencing scanty or deficit rain of 43%. Though month of July was deficit for the city, it again bounced back in August with 186.6 mm of rainfall, crossing the monthly average of 140 mm.
Northeast Monsoon
September is the last month before the onset of Northeast monsoon, which stretches from October to December. This season is considered to be the rainy season for the state as well as the city, unlike the Southwest Monsoon. Chennai receives more than 60 per cent of annual rainfall during these months.
The rainfall will increase incredibly both in terms of frequency and intensity during this season. There will be more number of rainy days in October, whereas the peak period for the season is November.
According to Skymet, the city will witness drop in temperatures, as October approaches. The maximum temperature will hover around lower 30s or even 30°C, while the minimum temperature will be in lower 20s. All these factors will lead to extremely pleasant weather conditions across the state.