Heavy rainfall hit parts of Chennai and Tiruvallur districts on Tuesday, December 2, 2025, in spells. The Regional Meteorological Centre (RMC) says moderate to intense showers will continue till the afternoon. The source of the rains is the deep depression, a remnant of cyclone Ditwah. It is moving southwest slowly at 3 kmph and has weakened into a depression. It lies over the west-central Bay of Bengal near north Tamil Nadu, Puducherry, and south Andhra Pradesh coasts, about 40 km east-southeast of Chennai. The closest point of the depression to the north Tamil Nadu-Puducherry coast is about 25 km. The depression will keep moving south-west towards the north Tamil Nadu-Puducherry coasts and keep its strength until 5:30 p.m. On Tuesday night, it will weaken into a low-pressure area. In the past 24 hours until 8:30 a.m. Tuesday, many places received heavy downpour. Ennore got an extremely heavy 26 cm rain. Parrys recorded 25 cm, Ice House 22 cm, Manali New Town and Ponneri 21 cm each. Basin Bridge, Chennai Collector Office and Perambur saw 20 cm each. Other places like Chennai, Manali, and Red Hills had 19 cm rainfall. With the weather system weakening and close to the coast, RMC issued a yellow alert for Chennai, Tiruvallur, Chengalpattu, and Kancheepuram districts. This alert means isolated heavy rains can occur today. The RMC's nowcast valid till 1 p.m. says light to moderate rains may happen in Ranipet, Tirupattur, Villupuram, Mayiladuthurai, Cuddalore districts, and Puducherry and Karaikal areas.