Full moon would inflict maximum damage: IMD

When cyclone Yaas makes landfall on Wednesday, it would coincide with the full moon perigean spring tide and inflict maximum damage, India Meteorological Department (IMD) officials have warned.

“The damage would be the maximum in the coastal districts of East Midnapore and South 24 Parganas,” said Sanjib Banerjee, deputy director, IMD Kolkata.

Experts said that the water level in the sea rises at least a metre high during a spring tide, which occurs during full moon, over a normal high tide that comes every day. The level is the highest during a perigean spring tide when the moon is the closest to earth. “The storm surge triggered by the cyclone at East Midnapore district would be 2-4 metres, while in South 24 Parganas it would be 1-2 metres. This is over and above the astronomical tide (spring tide),” he said.

For the storm surge, IMD has issued a ‘red’ warning — the highest level of warning — for East Midnapore district, and an ‘orange’ warning (where officials are asked to remain prepared) for South 24 Parganas district.

Yaas has already intensified into a ‘severe cyclone’ and is expected to gather more steam and become a ‘very severe cyclone’ by Tuesday late night on Wednesday noon.

“The water level is already high because of the spring tide... Sea and river water have gushed into some places along the coast and in the Sunderbans delta. Around nine lakh people have already been evacuated,” said West Bengal chief minister Mamata Banerjee.