A navy helicopter on a rescue mission in a flood hit area of Kerala.

AM Abdussalam, Correspondent

The unexpected heavy rains, flash floods and resulting landslides in Kottayam districts are triggered by the ‘cloudburst phenomenon,’ according to a study conducted by CUSAT (Cochin University of Science And Technology), Miami University, Indian Meteorological Department (IMD) and the Indian Institute of Tropical Meteorology based upon the pattern of rain received in the state since 2018.

This phenomenon was also responsible for the 2019 landslides at Kavalappara and Puthumala. CUSAT Advanced Centre for Atmospheric Radar Research director Dr Abhilash said that the small cloud clusters formed over a particular area resulted in heavy rains, causing a sudden rise in water levels and flash floods.

Normal rains stopped in Kerala on Oct.12 and there were no rains in the subsequent days until heavy downpour battered the state.

The weather was overcast on Saturday and it resulted in normal rains in many places. Cloudbursts are generally defined as sudden heavy rainfall of 10 centimetres in an hour. However, such a phenomenon has not been reported in the state.

But it can be dangerous even if it rains five centimetres in two hours which may cause landslides and flash floods. It is believed that the state received similar amount of rain in the last few days causing flash floods.

In 2018 and in the following years, rains lashed the state causing gradual increase in water levels. Landslides also followed causing major damage similar to the one that is now reported in eastern parts of Kottayam, Pathanamthitta, Konni, Seethathodu, Peermede and Poonjar, as all these regions received heavy rainfall.

However, IMD director general Dr Mrutyunjay Mohapatra rejected the assumption that the cause of torrential rain in Kerala was ‘cloudburst phenomenon.’

The low pressure and gusty winds have caused heavy rain in Kerala and the rain in turn led to landslides. He also said that the weather conditions of Kerala have changed substantially, according to reports.

Also on Sunday, a high wave warning has been issued for Kerala, Karnataka, Tamil Nadu and Lakshadweep coasts on October 18 till 11.30 pm.

"There is a possibility that sea will be rough near shore along the coast from 23:30 hours of 16th October 2021 to 23.30 hours of 18th October 2021 due to the effect of the high period (12-17 sec) swell waves, having heights of 2.5 - 3.3 m,” alerted Indian National Centre for Ocean Information Services (INCOIS).

The IMD has also forecasted that gusty weather with wind speed reaching 40-50 kmph is likely to prevail over the south Kerala coast. Fishermen are advised not to venture into the sea.

Incessant rainfall accompanied by lightning and thunder will continue in isolated places in Kerala from October 17 to 21. The IMD issued a ‘Yellow Alert’ in 11 districts on October 20 and 21.

Chief Minister Pinarayi Vijayan on Sunday requested people to be cautious in the wake of the heavy rains and flash floods in the state. He advised people to avoid getting into dangerous situations and to follow the directions of authorities during emergency situations.

A total of 105 relief camps have been opened across the state. Further arrangements have been made to open more camps on short notice if required.

The National Disaster Response Force (NDRF) teams have been deployed in Pathanamthitta, Alappuzha, Idukki, Ernakulam, Thrissur and Malappuram districts. In addition, five more teams will be deployed in Idukki, Kottayam, Kollam, Kannur and Palakkad districts. One of the two teams of the Indian Army is deployed in Trivandrum and one in Kottayam. The

Defence Security Corps (DSC) has deployed one team in Kozhikode and one in Wayanad. The Air Force and Navy were instructed to be prepared for any kind of emergency.

The Volunteer Force and Civil Defense are ready to deal with emergencies. The Engineer Task Force (ETF) team is also on the way to Mundakkayam from Bangalore. Two choppers of the Air Force reached state capital Trivandrum from Sulur near Coimbatore.