Sri Lanka would bear the brunt of a storm developing in the South-West Bay of Bengal while South Coastal Tamil Nadu would also be affected as the count-down starts from the weekend.
The US Climate Prediction Centre sees heavy to very heavy rain over Sri Lanka and South Coastal Tamil Nadu during the ongoing week ending November 28 (Tuesday next).
The European Centre for Medium-Range Weather Forecasts is of the view that this would be only a precursor to the elaborate wet weather that would continue into the week that follows.
It sees an intense low-pressure sitting smack over Sri Lanka by November 29 (Wednesday next) before it crosses into adjoining peninsular tip and emerges into the Arabian Sea.
It would lie spreadeagled over the region to begin with, before it parks itself as an individual trough/low-pressure area along the Kerala coast by December 1/2.
India Met Department (IMD) projections more or less convey the same scenario, with the heavy bands covering entire Kerala and Tamil Nadu from Tuesday/Wednesday.
It shows a remnant 'low' pressure area or part of the larger trough from South-West Bay extending across the southern peninsula and into the South-East Arabian Sea off Kerala by December 2.
'Low' stays put
Meanwhile, this morning, IMD said that the existing 'low' over Andaman Sea did not shift from last night's position. It is expected to start moving west-south-west towards the Sri Lanka coast soon.
It would set up the anchor system from which a likely storm would develop after getting additional feed of moisture from a circulation moving in from the tip of Indonesia.
Proximity to land features of Sri Lanka and South Tamil Nadu may not allow the combined system to grow beyond a point. Still, it would surf up enough moisture to cause heavy rain over the region.
According to a weather tracker of the US Climate Prediction Centre, the seas off Tamil Nadu and Sri Lanka would remain active until mid-December, up till when forecasts are available.
Satellite pictures this morning showed parcels of rain-bearing clouds drifting out all over the South and South-West Bay of Bengal and approaching the eastern coast of Sri Lanka.