Dana intensifies into severe cyclone, moves towards Odisha, Bengal coasts

Cyclone Dana intensified into a severe cyclone on Wednesday night and continued to move towards Odisha and West Bengal coasts. It lay centered about 180 km southeast of Paradip (Odisha), 210 km south-southeast of Dhamara (Odisha), and 270 km south of Sagar Island (West Bengal) on Thursday afternoon.
The system was likely to move north-northwestwards and cross north Odisha and West Bengal coasts between Puri and Sagar Island close to Bhitarkanika and Dhamara (Odisha) from midnight of Thursday to Friday morning as a severe cyclonic storm with a wind speed of 100-110 kmph gusting 120 kmph. The system is under continuous surveillance by the Doppler Weather Radar at Paradip.
The size of the system is around 370 km. On Thursday afternoon, it was traversing warm waters over the northwest Bay of Bengal. The sea surface temperature (SST) was around 30 degrees C over central and north Bay of Bengal. The tropical cyclone heat potential was >100 kj/cm2 over the west-central Bay of Bengal. There are chances that Dana’s intensity may increase further, marginally before landfall, officials said.
As per the India Metrological Department (IMD) bulletin, its peak wind speed may be 105-115 gusting to 125 kmph on Thursday evening. “The fact that severe cyclone Dana had a shorter travel time over the sea may have helped prevent intensification to extreme category. The cyclone developed very close to the coast and hence its life is short. Yet, it’s a severe cyclone. It has increased intensity mainly because of warm SST. Over North Bay, the temperatures are higher even at depth so that helps the system intensify. Dry air from land will also help counter the intensity of Dana when landfall begins,” said an IMD official. He added that there are two large rivers Baitarini and Brahmani near the landfall zone. “There is a large delta area so the landfall process may take relatively longer,” he said.
“Enhanced poleward outflow is seen in mid-latitude westerlies…high SST, poleward outflow, moderate wind shear would support further intensification of the system. Most of the models are indicating further intensification of the cyclonic storm into a severe cyclonic storm over the northwest Bay of Bengal,” Tropical Cyclone Advisory by Regional Specialised Meteorological Centre said.
Heavy to very heavy rainfall at a few places and extremely heavy rainfall (≥ 21 cm) at isolated places was expected in Baleswar, Mayurbhanj, Bhadrak, Kendrapara, Jagatsingpur Kendujhar, Jajpur, Cuttack and Dhenkanal, Khorda and Puri districts of Odisha on Thursday and Friday.
Heavy to very heavy rainfall at a few places with extremely heavy rainfall was likely at isolated places in South and North 24 Parganas, East and West Medinipur, Jhargram, Howrah, Hooghly, Kolkata, and Bankura districts of Gangetic West Bengal on Thursday and Friday. Light to moderate rainfall at most places was likely in south Jharkhand with heavy rainfall at isolated places on Thursday and heavy to very heavy rainfall at isolated places on Friday.
According to RMSI, a global GIS consulting and risk management company, this cyclone will likely impact 34,000 buildings, 1,200 essential facilities, 3 railway stations, ~440 km of road length, ~5500 km of electricity network, and ~250 km of oil and gas network. Essential facilities include schools, healthcare, fire stations, and police stations. This impact will be concentrated in Jagatsinghpur, Kendrapara, Puri, Bhadrak, Baleswar, Cuttack, Ganjam, and Jajpur districts as per RMSI’s modeling for Odisha.