Authorities in monsoon-weary Kerala reinstated red alerts in a number of districts after calling them off on Thursday morning, with a productive cyclonic circulation threatening to stay put off the Andhra Pradesh coast. This circulation may gradually yield space to a low-pressure area likely by Sunday, adding heft to the ongoing heavy rain spell.
Red alerts were back in force in Pathanamthitta, Kottayam, Alappuzha, Ernakulam, Idukki, Thrissur, Palakkad and Kannur districts. People in areas ravaged by the 2018 and 2019 floods have been advised to shift to safer places. An orange alert has been issued in Malappuram, Kozhikode, Wayanad, Kasaragod and Kollam and a yellow alert in Thiruvananthapuram.
Many rivers in spate
The water level in the Pampa, Manimala and Achenkoil are rising fast, reviving memories of 2018 when these rivers wrought the maximum damage in the midlands in Central Kerala. Nine teams of the National Disaster Response Force have been deployed in the most vulnerable districts. A red alert has been declared at a number of small dams, while a blue alert, lowest on a scale of three, has been declared at Idukki. The Pathanamthitta Collector has urged pilgrims to the Sabarimala hill shrine to start their descent not later than 6 pm. Pilgrims from the base station will not be allowed the trek from 3 pm.
Helpful monsoon features
Besides the cyclonic circulation, a shear zone of monsoon winds and turbulence in the higher regions over Kerala and Tamil Nadu, fuelled Thursday’s heavy showers. The shear zone is likely to gradually shift northwards in the next four-five days, bringing more parts of Tamil Nadu and Karnataka and further northward under its influence. Also, the monsoon trough over the plains of North India lies South of its normal position, playing its role to perfection.
Widespread rain forecast
The India Meteorological Department (IMD) has forecast fairly widespread to widespread rainfall with isolated heavy falls, thundershowers and lightning over Lakshadweep on Thursday; Rayalaseema on Friday; coastal Andhra Pradesh from Saturday to Monday; Tamil Nadu, Puducherry and Karaikal from Thursday to Saturday; and over Telangana, Karnataka, and Kerala and Mahe from Thursday to Monday.
US agency forecast
The US Climate Prediction Centre agreed with the IMD, pointing to a low-pressure area (even depression) forming over the Bay of Bengal along with a twin system with friendly flows looking in from the South China Sea. This will keep the monsoon busy over the South Peninsula until August 9 (Tuesday next). The US agency sees a successor shaping up over the Bay during the subsequent week (August 10-16), sending the monsoon current back into Central India and adjoining North-West India on the back of a pulse of the Madden-Julian Oscillation (MJO) wave transiting Africa.
Tenure over South Peninsula
Meanwhile, the IMD predicted isolated extremely heavy rainfall over the ghat areas of Tamil Nadu and Kerala on Thursday and over Coastal and South Interior Karnataka on Friday. The intense rainfall over Tamil Nadu, Kerala and Karnataka may reduce after three days. From Saturday, rainfall will scale up over Gujarat, East Rajasthan, Maharashtra, Goa, Telangana, Chhattisgarh, Madhya Pradesh and Odisha.
The 24 hours ending Thursday morning saw heavy to very heavy rainfall at isolated places over Haryana, Uttarakhand, Chhattisgarh, South Interior Karnataka, Tamil Nadu, Jharkhand and Kerala, and heavy over Himachal Pradesh, Delhi, coastal Andhra Pradesh, Telangana, Rayalaseema, Assam, Meghalaya, North Interior Karnataka, Madhya Pradesh, Madhya Maharashtra, Marathwada and Mizoram.