The onset phase of the South-West monsoon is likely to witness the birth of a fresh storm in the Bay of Bengal, say global weather models.
The Australian Bureau of Meteorology said on Tuesday that the monsoon is already causing heavy rainfall over the eastern Bay of Bengal, the Myanmar coast and parts of the Malay Peninsula.
The monsoon had entered the Andaman and Nicobar Islands, its first outpost in Indian territorial waters (eastern Bay) around the normal date but has been stuck there for over 10 days. The normal date of onset over Kerala is June 1, but the India Met Department had assessed in advance that the arrival here would be delayed until June 7, with a model error of four days.
Right now, many parts of Kerala are receiving thundershowers, which have been classified as a pre-monsoon development.
According to the Australian Met, the presence of an active ‘trough’ – within which the monsoon sustains – as well as continuing thunderstorm activity, heightens the risk of storm formation over the Bay of Bengal.
Cyclone watchThe northern Bay of Bengal and the North-West Pacific region have an increased chance of cyclone development during June 1-14, it said.
The European Centre for Medium-Range Weather Forecasts too agrees with the assessment of the Australian Met. It visualises a well-marked low-pressure area over coastal Andhra Pradesh waiting to step out into the Bay waters by June 10.
This well-marked ‘low’ can in turn be traced to a cyclonic circulation parked for days together over Lakshadweep and Kerala, and persisting on Tuesday. The circulation will move north towards Konkan, before being gulped up by a western disturbance and carried across the peninsula towards coastal Andhra Pradesh.
Even as these activities get under way, monsoon flows across the Arabian Sea will get strengthened in due course.
The low-pressure area over coastal Andhra Pradesh will pull in the flows even stronger and drive the monsoon to a peak by June 10, the European Centre assessed. Meanwhile, there is no heat wave warning over land for the next five days as rain/thunderstorms line up all over North-West India, East and North-East India, and the South Peninsula.
Heavy rain is expected to start pelting Kerala, Lakshadweep, South Interior Karnataka and Coastal Karnataka from the weekend, in what is believed to be a perfect build-up to onset of the monsoon.
India Met Department has retained its prediction of a sustained increase in rain/thunderstorm activity over the rest of the West Coast from Monday (June 5).