The country as a whole has continues to record surplus summer showers since March 1, even as the season prepares to transition into pre-monsoon.
Most of the southern States which had run up rain deficits for the third time on a trot (including the 2016 monsoon that proved beneficial for North India only) have been receiving excess showers in recent times.
A fresh wave of showers is forecast to visit Kerala and adjoining parts of Tamil Nadu from April 13, according to the US Climate Prediction Centre.
According to the US National Centres of Prediction, the showers will spread out from Kerala into Karnataka, Telangana, Andhra Pradesh and parts of Maharashtra from April 15.
But the intervening week (April 6-12) is likely to witness largely dry conditions over this region, especially Kerala and adjoining Tamil Nadu.
Weather watchers are also scanning the eastern Bay of Bengal for signs of the first pre-monsoon low-pressure area that usually makes its appearance during this time of the year.
An India Met Department (IMD) update pointed to a circulation hovering above the Malay Peninsula across the international waters, east-southeast of Bay of Bengal. But none of the weather models predicted any ‘significant development’ in the adjoining seas that could be of relevance to the Bay of Bengal any time soon.
Meanwhile, Lakshadweep registered surplus rain of 466 per cent during March 1 to April 5. Tamil Nadu followed with +315 per cent, and Kerala, +115 per cent. According to the IMD, nine States recorded ‘large excess’ rain (exceeding 60 per cent) during the period. Eight States recorded ‘excess’ rain (between +20 per cent and +59 per cent).
The showers were normal in four, deficient in eight, and ‘large deficient’ (between -99 per cent and -60 per cent) and ‘no rain’ (-100 per cent) in four.
Most of the rain-deficit areas are in West, North and North-West India. This is despite the frequent arrivals of western disturbances, more of which have been forecast next week.
The IMD has forecast thunderstorms accompanied with hail at some places in North-West, East and North-East India during the weekend and into the beginning of the next as western disturbances check into the region afresh. Western disturbances are the principal weather makers over the region during the winter and also into the spring, sometime extending their stay into the pre-monsoon.
However, the resultant showers and dust storms interfere with the heating process over land. This is not ideal for the development and propagation of the South-West monsoon.