The current lull in organised weather over the South Peninsula would be broken by ‘easterly waves’ across the Bay of Bengal with parts of Tamil Nadu, Kerala and Sri Lanka to be affected from the weekend into early December.

Easterly waves are fast-moving low-pressure waves across the Bay and are frequent during the North-East monsoon. Some of the ‘rain heads’ packing the wave have gone on in the past to become low-pressure areas and depressions, even cyclones. But no such intensified form of weather is being forecast this time round in the Bay.

This is the latest bit of good news after a slow moving well-marked low-pressure area produced enough rain to lower the overall rain deficit to 10 per cent in Tamil Nadu and Puducherry; 1 per cent in Kerala; and 6 per cent in Lakshadweep.

This is, however, not to deny that there are serious shortcomings in the spatial spread of the rains with even the district of Chennai reeling with a deficit of 47 per cent. Dharmapuri and Krishnagiri have posted bigger deficits of 53 per cent each, followed by Karur (46 per cent); Salem (43 per cent); and Tiruchirappalli (41 per cent) with a deficit of 40 per cent and above.

It remains to be seen how far spread out the rains generated by easterly waves will be.

On Monday, the India Met Department (IMD) forecast heavy rainfall at isolated places over Coastal Tamil Nadu. Its projections into the first week of December, too, showed prospects of continued easterly wave activity.

comment COMMENT NOW