An existing low-pressure area beat forecasts to intensify twice over to become the latest depression in the Bay of Bengal on Tuesday.
The intensification into a well-marked ‘low’ and then as depression took place overnight causing the system to also track that now faced coastal Andhra Pradesh.
MAY INTENSIFY
The Met Department located it to 600 km east-northeast of Chennai; 500 km east-southeast of Machilipatnam; and 430 km southeast of Visakhapatnam on Tuesday afternoon.
It said that the depression would intensify into a deep depression (just below cyclone status) and cross south Andhra Pradesh and adjoining north Tamil Nadu coast by Thursday night.
The area of landfall is projected between Chennai and Ongole, according to the initial assessment by the Met Department.
Meanwhile, another ‘low’ is forecast to develop over South Andaman Sea around Friday and intensify further.
Indications are that this too could grow to the level of a depression and head towards north Tamil Nadu and adjoining south Andhra Pradesh coast over the next 10 days.
But some models took it extreme south Tamil Nadu, adjoining north Sri Lanka and later into southern Kerala.
Around this time, west Pacific/South China Sea next door will have seen the birth of another likely storm. International weather agencies have put these seas under watch yet again.
This has relevance for Bay of Bengal since previous such disturbances from there have sent in remnants into the Bay where they regenerated as ‘low’s/depressions.
RAINS FORECAST
An extended outlook suggested that rainfall activity will scale up once again over the south peninsula from the weekend.
The Met Department said that Tuesday will have already seen isolated heavy rainfall over south Tamil Nadu and Kerala.
On Thursday, isolated heavy to very heavy rainfall is forecast for coastal Andhra Pradesh and coastal Tamil Nadu as the likely deep depression crosses coast.
The Climate Prediction Centre of the US National Weather Services said that the Andhra Pradesh coast will receive very heavy rainfall from November 25 to December 1.
MERCURY DIPS
In the North, night temperatures are below normal by 2 to 4 degree Celsius over parts of northwest and central India; Odisha; Jharkhand; the northeastern States and Gujarat.
The drop in mercury has occurred as the warmth provided by a prevailing low-pressure western disturbance moves away from Jammu and Kashmir.
The chill will lift only when the next western disturbance with an ‘steaming engine’ upfront (moisture load) crosses in to Jammu and Kashmir by Saturday.