Chennai and nearby districts, including Kancheepuram, Tiruvallur, and Chengalpet, are forecasted to experience significant rainfall ranging from 6 cm to 12 cm in isolated areas until November 15. This weather activity is due to a low-pressure system forming over the southwest Bay of Bengal, which is expected to move toward Tamil Nadu and Sri Lanka in the upcoming days.
IMD Issues Yellow Alerts Across Tamil Nadu
The India Meteorological Department (IMD) has issued yellow alerts for several districts. On November 12, alerts cover 12 districts, followed by 17 districts on November 13, expanding to 27 districts by November 14, and then covering 25 districts on November 15.
In a recent bulletin, the IMD stated, “For the next 48 hours, the city and its suburbs may experience moderate to heavy rainfall with thunderstorms and lightning in some areas. Skies may be partly cloudy. The maximum temperature is expected to be around 32°C-33°C, and the minimum around 25°C.”
Rainfall to Spread Across Coastal and Interior Regions
The rain is expected to begin along the coastal districts from Tiruvallur to Ramanathapuram starting November 12. By November 13, it will likely spread to surrounding areas, extending to southern interior and some western regions by November 14. On November 15, coastal, northern, and southern districts are expected to see heavy rainfall, while showers may move to western and northern interior districts by November 16 and 17.
Active Monsoon Phase and Rainfall Deficits
An active monsoon phase starting on November 12 is anticipated to bring much-needed rainfall to many areas, addressing rainfall deficits. Weather blogger Pradeep John noted that “from Nov 12, the active phase of the monsoon picks up, beginning with Chennai, Kancheepuram, Tiruvallur, and Chengalpet, followed by other parts of Tamil Nadu.”
Due to deficits this season, Kancheepuram recorded only 19 cm of rain since October 1 (36% shortfall), Tiruvallur has seen 31 cm (6% deficit), and Chengalpet has 25 cm (31% shortfall). However, Chennai itself has recorded 43 cm, showing a slight surplus of 1%.
Rainfall Statistics for the Season in Tamil Nadu
Since October 1, Chennai has seen a slight excess in rainfall with 43 cm, while Tamil Nadu as a whole recorded 26 cm, also showing a 1% surplus compared to the seasonal average.
