After a recess, rains are set to escalate over the South Peninsula even as the ongoing heavy spell over the plains of North-West India reduces in intensity, an India Meteorological Department (IMD) update said, in line with the outlook from its own as well as global weather models for an uptick monsoon activity in the South from August.

Troughs, circulation present

The IMD said an unusual and non-monsoon-like trough runs from South Chhattisgarh to Comorin across Telangana, Rayalaseema and Tamil Nadu, while a second trough runs from the central parts of South Bay of Bengal to Comorin across South Sri Lanka. These apart, a cyclonic circulation hovers over Rayalaseema, making for a predominantly pre-monsoon framework of systems.

More stable system to evolve

The trough originating from the Bay is forecast to re-orient towards the East Peninsular Coast (around Chennai) and align itself along but along and convert itself into a proper monsoon system off the Andhra Pradesh/Odisha coast later into the week.. Forecasts suggest it will be a harbinger for a stronger system capable of rallying the flows around and powering the monsoon in that location to signal another productive session over East and Central India during the first ten days of August.

Heavy rain for the hills

Outlook for the next few days for North-West India indicated continued heavy to very heavy rainfall for the hills for the next five days even as rains reduce in intensity over the plains.

The presence of the monsoon trough will trigger very heavy rainfall likely overover Bihar on Monday while it will be heavy over the remaining parts of East and North-East until Tuesday before a let-up.

Widespread over South Peninsula

As for the South Peninsula, the north-south trough over land and the circulation in the Bay will combine to bring fairly widespread to widespread rainfall with isolated heavy falls, thunderstorms and lightning over Coastal Andhra Pradesh and Rayalaseema from Monday to Wednesday; over Telangana, South Interior Karnataka, Tamil Nadu, Puducherry and Kerala till Monday; and North Interior Karnataka and Lakshadweep, on Tuesday and Wednesday.

May last until the weekend

Isolated very heavy rainfall is likely over Rayalaseema on Monday; Coastal Karnataka and Kerala, from Monday to Wednesday; South Interior Karnataka, on Tuesday and Wednesday; and over Tamil Nadu and Puducherry until Wednesday.

An extended outlook valid for three days from August 5 to 7 (Friday to Sunday) said fairly widespread to widespread light or moderate rainfall is likely over Central, East, and North-East India.

Scattered to fairly widespread light to moderate rainfall is likely over North-West India and the South Peninsula. Isolated, scattered light to moderate rainfall is likely over West India and Rajasthan.