Outer spiral bands of Cyclone Mandous reached the coast and the landfall process started at 10 p.m., bringing more intense rains in coastal areas.
The centre of cyclone remained in the ocean at 10.30 p.m. and it would take another two or three hours for the entire cyclone to cross the coast.
The cyclone moved at a speed of 14 kmph. Squally winds gusting up to 85 kmph may blow along Tamil Nadu, Puducherry and southern A.P. coast till Saturday morning and decrease gradually. Places like Chennai, Tiruvallur, Ranipet started experiencing strong surface winds of 50 to 60 kmph around 9 p.m. on Friday, said S. Balachandran, Additional Director-General of Meteorology, Chennai.
Kattupakkam and Kalavai in Kancheepuram and Chennai recorded heavy rains of 10 cm between 8.30 am and 10.30 p.m. on Friday. The weather stations and rain gauges in and around Chennai too recorded heavy rains. Meenambakkam saw 7.7 cm and Madhavaram 7.8 cm. Reservoirs in Red Hills, Cholavaram and Chembarambakkam had recorded 10 cm and 7 cm respectively at 10 p.m.
Over 470 personnel of the National Disaster Response Force (NDRF) and State Disaster Response Force (SDRF) were deputed to Chengalpattu, Chennai, Cuddalore, Kancheepuram, Mayiladuthurai, Nagapattinam, Thanjavur, Tiruvallur, Tiruvarur and Villupuram districts, with Tamil Nadu Chief Minister M.K. Stalin personally taking stock of the preparedness by the administration to meet any eventuality. A few hours before the landfall, Mr. Stalin visited the State Emergency Operations Centre (SEOC) at Ezhilagam complex in Chennai and reviewed the precautionary measures.
The State Transport Corporation decided to suspend bus operations for more than four hours on the East Coast Road and Mamallapuram during the landfall.
In the past 121 years (1891-2021), 12 cyclones have crossed the coast between Chennai and Puducherry. Cyclone Mandous was the 13 th to make landfall in the region.
Many places in and around Chennai received moderate rains till 5.30 p.m. However, rain turned more intense after 5.30 p.m. over the coastal belt.
Over 15 flights to several cities including Kozhikode, Tiruchi, Hubballi, Mysuru, Madurai, Vijayawada, Thoothukudi, Kadapa, Bengaluru, Abu Dhabi and Colombo were cancelled at Chennai airport owing of the cyclone impact.
Earlier on Friday, S. Balachandran, Additional Director General of Meteorology, Chennai had said the data from S-band radar showed that the cyclone had squally winds of 70-80 kmph around it. Coastal areas too would experience gusty surface winds.
It was being monitored by doppler weather radars in Karaikal and Chennai.
The remnants of the system, which is likely to gradually weaken as it moves inland, would draw moisture from easterly winds and have an impact for two more days. The system, which may weaken as deep depression within three hours of landfall, may take the route along places like Krishnagiri before it reaches the Arabian sea. This would bring light to moderate rains in most places on Saturday as well after the landfall. Isolated heavy to very heavy rains too are possible over north Tamil Nadu, he said.
A cyclone would normally take two to three hours to make a landfall. It can move with an average speed up to 20 kmph and cyclone Mandous moved at a speed of 12-15 kmph.
On delta districts receiving less rains than predicted, he said rain intensity may vary according to the changing dynamics of the cyclone. Weather models had their limitations too. Various factors like windshear and interaction of the system with sea surface and top level of atmosphere may either destabilise or strengthen the cyclones.
On Friday, Chennai experienced a dip in the day temperature to 23.7 degree Celsius and squally weather as the storm lay centred around 60-70 kmph from the Bay.
In the recent past, Cyclone Nivar (November 2020) and cyclone Nilam (November 2012) were some of the cyclones that made a landfall close to Puducherry and Mamallapuram. Cyclone Nivar crossed coast near Puducherry as a severe cyclonic storm and dumped extremely heavy rains in coastal areas.
Andhra steps up preparedness
Officials in Nellore, Prakasam and Chittoor districts in Andhra Pradesh have been put on alert. Incessant rain accompanied by strong winds lashed different parts of south coastal Andhra Pradesh under the influence of Mandous on Friday.
Teams of the NDRF and State Disaster Response Force moved to the coastal villages to rescue people in trouble. Irrigation authorities stepped up water release by 10,000 cusecs from Somasila reservoir
In Chittoor distirct, Collector M. Hari Narayanan asked officials to evacuate people to safer places in case of any possibility of inundation. Officials have been instructed to closely monitor the water levels in water bodies and release them downstream, whenever required, to avoid breaches and submerging of crops.